CN115599101A

CN115599101A - Method for detecting walking distance by robot and mobile robot

Info

Publication number: CN115599101A
Application number: CN202211344154.3A
Authority: CN
Inventors: 王悦林; 梁铧杰; 赖钦伟
Original assignee: Zhuhai Amicro Semiconductor Co Ltd
Current assignee: Zhuhai Amicro Semiconductor Co Ltd
Priority date: 2022-10-31
Filing date: 2022-10-31
Publication date: 2023-01-13

Abstract

The application discloses a method for detecting a walking distance by a robot and a mobile robot, wherein the method for detecting the walking distance by the robot comprises the following steps: after the robot enters a walking state from a static state, the robot starts to walk on a working surface and acquires a first PWM value, and then the acquired first PWM value within a specific PWM value range is subjected to integral processing to determine a reference walking distance value of the robot; or in the process that the robot walks on the working surface, the robot sets the travel distance value measured in real time by the code disc installed on the robot as the reference travel distance value of the robot; applying a matched distance conversion coefficient for the reference walking distance value of the robot by combining the relation between the walking direction of the robot and the gravity direction, and calculating a walking distance correction value of the robot; the robot keeps closed-loop adjustment of a PWM value used for controlling the driving motor, and obtains a first PWM value in the closed-loop adjustment process.

Description

Method for detecting walking distance by robot and mobile robot

Technical Field

The application relates to the technical field of mobile robots, in particular to a method for detecting walking distance by a robot and the mobile robot.

Background

Cleaning robots using inertial sensor navigation include floor sweeping robots, window wiping robots, floor washing robots, and the like. The window cleaning robot is adsorbed to the vertically arranged glass surface; when the window cleaning robot walks upwards on the glass surface, the window cleaning robot applies work to gravity, and a driving wheel motor of the window cleaning robot needs to output partial power to overcome the influence of the gravity so as to walk upwards; when the window cleaning robot walks downwards on the glass surface, gravity acts on the window cleaning robot, and if the window cleaning robot does not take a braking action, the gravity can push the window cleaning robot to accelerate to walk downwards; moreover, if the window cleaning robot walks upwards, downwards, leftwards or rightwards on the glass, the time consumed by the driving wheels to rotate forwards and backwards for the same distance is different based on different current characteristics generated by the forward rotation and reverse rotation of the motors of the driving wheels and different torque forces required by the forward rotation and reverse rotation of the driving wheels; therefore, the actual traveling speed of the window cleaning robot on the glass surface is different from the standard traveling speed of the driving wheel calculated by the fixed PWM value of the motor, and the traveling distances measured when the robot travels through the same path in different directions are different, which affects the path planning of the window cleaning robot on the glass surface.

Disclosure of Invention

The application discloses a method for detecting walking distance by a robot and a mobile robot, and the specific technical scheme is as follows:

the robot detection walking distance method includes that driving wheels are installed on two sides of the robot, and a driving motor electrically connected with the driving wheels is installed inside the robot; the robot is also provided with a fan for adsorbing the robot on a working surface; the method for detecting the walking distance by the robot comprises the following steps: after the robot enters a walking state from a static state, the robot starts to walk on a working surface and acquires a first PWM value, and then integration processing is carried out on the acquired first PWM value within a specific PWM value range to determine a reference walking distance value of the robot; or in the process that the robot walks on the working surface, the robot sets the travel distance value measured in real time by the code disc installed on the robot as the reference travel distance value of the robot; applying a matched distance conversion coefficient for the reference walking distance value of the robot by combining the relation between the walking direction of the robot and the gravity direction, and calculating a walking distance correction value of the robot; the robot keeps performing closed-loop adjustment on a PWM value used for controlling the driving motor, and obtains a first PWM value in the closed-loop adjustment process.

Further, before the robot starts to walk, the first PWM value is loaded to the driving motor to control the driving wheel to rotate so as to overcome the static friction force of the working surface until the first PWM value is larger than a preset starting threshold value, the robot is determined to enter a walking state from a static state so that the walking speed of the robot is in a linear relation with the first PWM value obtained in real time, and then the robot starts to walk on the working surface so as to overcome the blocking effect of the static friction force from the working surface; the preset starting threshold value is a PWM value determined by setting that the driving wheels of the robot enter the walking state on working surfaces with different friction forces; the arrangement mode of the working face comprises vertical arrangement, horizontal arrangement or inclined arrangement.

Further, the method for integrating the acquired first PWM value within the specific PWM value range includes: after the robot enters a walking state, the robot samples first PWM values within preset sampling time, then integrates all the first PWM values sampled within the preset sampling time and larger than a preset starting threshold value, and then sets the integration result of the first PWM values as a reference walking distance value of the robot; the specific PWM value range refers to a PWM value range which is larger than a preset starting threshold value; and within the preset sampling time, the walking speed of the robot is in direct proportion to the first PWM value sampled by the robot.

Further, in the preset sampling time, a timer arranged in the robot triggers an interrupt signal every other unit sampling time, and the robot samples the first PWM value once when detecting the interrupt signal once; and the first PWM value is used for feeding back the walking speed of the robot in each unit sampling time.

Further, the method for calculating the walking distance correction value of the robot by applying the corresponding distance conversion coefficient to the reference walking distance value of the robot in combination with the relationship between the walking direction of the robot and the gravity direction includes: the robot measures the walking direction of the robot on a working surface in real time through a gyroscope, and determines the pose relation between the walking direction of the robot and the gravity direction; when the walking direction of the robot is not perpendicular to the gravity direction, if the walking direction of the robot is arranged upwards relative to a horizontal plane, the robot is determined to walk upwards on a working surface relative to the horizontal plane, and the currently calculated reference walking distance value is controlled to be multiplied by a first distance conversion coefficient, so that the walking distance correction value of the robot is determined; when the walking direction of the robot is not perpendicular to the gravity direction, if the walking direction of the robot is arranged downwards relative to the horizontal plane, the robot is determined to walk downwards on the working surface relative to the horizontal plane, and the currently calculated reference walking distance value is controlled to be multiplied by a second distance conversion coefficient, so that the walking distance correction value of the robot is determined; wherein the working surface is not arranged parallel to the horizontal plane; the direction of gravity is vertically downward.

Further, when the robot walks upwards on the working surface relative to the horizontal surface, the walking direction of the robot is set to be a first preset inclined direction; when the robot walks downwards on the working surface relative to the horizontal surface, the walking direction of the robot is set to be a second preset inclined direction; the first preset inclined direction and the second preset inclined direction are symmetrical; on the same working surface, the first distance conversion coefficient and the second distance conversion coefficient are reciprocal; the time spent by the robot walking in the first preset inclined direction through the first preset reference distance value is marked as upward test time, and the time spent by the robot walking in the second preset inclined direction through the first preset reference distance value is marked as downward test time; on the premise that the ratio of the downward test time to the upward test time is set as a first distance conversion coefficient by the robot, when the robot walks on the working surface along a first preset inclined direction, the calculated walking distance correction value of the robot is smaller than a reference walking distance value; on the premise that the ratio of the downward test time to the upward test time is set as a second distance conversion coefficient by the robot, when the robot walks in a second preset inclined direction on the working surface, the calculated walking distance correction value of the robot is smaller than the reference walking distance value; on the premise that the ratio of the upward test time to the downward test time is set as a first distance conversion coefficient by the robot, when the robot walks on the working surface along a first preset inclined direction, the calculated walking distance correction value of the robot is greater than a reference walking distance value; and on the premise that the ratio of the upward test time to the downward test time is set as the second distance conversion coefficient, when the robot walks in the second preset inclined direction on the working surface, the calculated walking distance correction value of the robot is greater than the reference walking distance value. Thereby applying a matching distance conversion coefficient to the reference walking distance value of the robot.

Further, a first preset reference distance value is used for representing the distance between the boundary of the uppermost end of the working surface and the boundary of the lowermost end of the working surface; the robot linearly walks to the boundary of the uppermost end of the working surface from the boundary of the lowermost end of the working surface along a first preset inclined direction, and the consumed time is upward test time; and the robot linearly travels to the boundary of the lowest end of the working surface from the boundary of the uppermost end of the working surface along a second preset inclined direction, and the consumed time is downward test time.

Further, the method for calculating the walking distance correction value of the robot by applying the corresponding distance conversion coefficient to the reference walking distance value of the robot in combination with the relationship between the walking direction of the robot and the gravity direction further includes: when the walking direction of the robot is vertical to the gravity direction, if the walking direction of the robot is a first preset horizontal direction vertical to the gravity direction, controlling the currently calculated reference walking distance value to be multiplied by a third distance conversion coefficient, and determining a walking distance correction value of the robot; when the walking direction of the robot is vertical to the gravity direction, if the walking direction of the robot is a second preset horizontal direction vertical to the gravity direction, controlling the currently calculated reference walking distance value to be multiplied by a fourth distance conversion coefficient, and determining a walking distance correction value of the robot; the first preset horizontal direction points to one side of the working surface, and the second preset horizontal direction points to the other side of the working surface.

Further, the time spent by the robot walking in the first preset horizontal direction for the second preset reference distance is marked as first test time, and the time spent by the robot walking in the second preset horizontal direction for the second preset reference distance is marked as second test time; the robot sets the ratio of the first test time to the second test time as a third distance conversion coefficient; or the robot sets the ratio of the second test time to the first test time as a third distance conversion coefficient; the first preset horizontal direction and the second preset horizontal direction are symmetrical; and on the same working surface, the third distance conversion coefficient and the fourth distance conversion coefficient are reciprocal.

Further, the second preset reference distance value is a distance between a boundary of a leftmost end of the working face and a boundary of a rightmost end of the working face; the robot linearly walks to the boundary of the rightmost end of the working surface from the boundary of the leftmost end of the working surface along a first preset horizontal direction, and the consumed time is first test time; and the robot starts to linearly walk from the boundary of the rightmost end of the working face to the boundary of the leftmost end of the working face along a second preset inclination direction, and the consumed time is second test time.

Further, if the working surface is parallel to the gravity direction, the robot is configured to be adsorbed on the working surface, and the driving wheels of the robot are allowed to rotate forwards or backwards on the working surface when the robot walks on the working surface; if the working surface is perpendicular to the gravity direction, the robot is not configured to be adsorbed on the working surface, and the driving wheels of the robot are allowed to rotate forwards or backwards on the working surface when the robot walks on the working surface.

Further, the method of closed-loop regulating the PWM value for controlling the driving motor includes: under the condition that the absolute value of the angle difference value between the course angle measured by the robot in real time and the target navigation angle in the current regulation period is not within the preset angle error range, carrying out PID regulation on the PWM value for controlling the driving motor by the robot, in the process of carrying out PID regulation on the PWM value for controlling the driving motor, taking the difference value between the PWM value for controlling the driving motor and the first preset target PWM value in the current regulation period as the feedback input of the next regulation period so as to reduce the difference value between the PWM value for controlling the driving motor and the first preset target PWM value, setting the PWM value for controlling the driving motor as the first PWM value, and then inputting the first PWM value into the driving motor on the corresponding side in real time to obtain the driving wheel current sampling value output by the driving motor on the side, wherein after the robot enters the walking state, the real-time rotating speed of the driving motor is in direct proportion to the first PWM value; for the driving motors correspondingly connected with the driving wheels arranged on each side of the robot, when the PWM value used for controlling the driving motors on the corresponding side and the first preset target PWM value are smaller than the steady-state error of the corresponding preset driving wheels, the robot adjusts the walking direction based on the difference value of the real-time rotating speeds of the driving motors on the two sides so as to guide the absolute value of the angle difference value between the course angle of the robot and the target navigation angle to be within the preset angle error range; the absolute value of the angle difference between the course angle of the robot and the target navigation angle and the absolute value of the difference between the real-time rotating speeds of the driving motors correspondingly connected with the driving wheels arranged on the two sides of the robot form a positive correlation; the course angle of the robot is measured in real time by a built-in gyroscope of the robot; the driving wheels arranged on the two sides of the robot are respectively connected with a driving motor; the target navigation angle is pre-planned by the robot to guide the robot to walk along the pre-planned working path.

A mobile robot is characterized in that the left side and the right side of the mobile robot are respectively provided with a driving wheel, and a driving motor electrically connected with the driving wheels is arranged in the mobile robot; the mobile robot is also provided with a fan for adsorbing the mobile robot on a working surface; the mobile robot is configured to perform a method of the robot detecting a walking distance.

Further, when the mobile robot is a sucker type window cleaning machine, the driving wheels arranged on the left side and the right side are cleaning turnplates and are used for supporting the sucker type window cleaning machine to move on the work surface adsorbed by the sucker type window cleaning machine.

In the application, the robot walks in the working face placed in various directions, the integral result of the first PWM value of the robot on the output current stabilization stage of the driving motor to the time is calculated by using the first PWM value adjusted in a closed loop, and the integral result is used as the walking distance of the robot to be corrected on the working face, the walking distance condition of the robot is preliminarily reflected, and the walking distance degree of the current position of the robot relative to the starting position of the walking state can be detected.

On the basis of detecting the distance of the robot to the starting point position of the walking state, the following distance correction effects exist:

if the robot walks upwards along the vertically arranged working face or upwards along the obliquely arranged working face, controlling the currently calculated reference walking distance value to be multiplied by a first distance conversion coefficient, determining a walking distance correction value of the robot, and obtaining standard distance information; or if the robot walks downwards along the vertically arranged working face or downwards along the obliquely arranged working face, the currently calculated reference walking distance value is controlled to be multiplied by the second distance conversion coefficient, the walking distance correction value of the robot is determined, and standard distance information is obtained. The influence of the gravity of the robot on the walking of the robot on the current walking surface and the rotation speed difference caused by the difference of the rotation directions of the driving wheels of the robot are overcome, the corrected value of the distance traveled upwards can be represented by the distance information traveled downwards, and the difference caused by the gravity influence and the positive and negative rotation of the driving wheels is overcome for the path planning of the robot in the vertical upwards direction or the inclined upwards direction; the corrected value of the distance traveled downwards can be represented by the distance traveled upwards, and the difference caused by gravity influence and positive and negative rotation of the driving wheels can be offset for planning the path of the robot in the vertical downwards direction or the inclined downwards direction.

If the robot walks in the horizontal direction along a vertically arranged working surface, or walks in the horizontal direction along an obliquely arranged working surface, or walks along a working surface arranged in parallel with the horizontal plane, controlling the currently calculated reference walking distance value to be multiplied by a corresponding distance conversion coefficient, and determining a walking distance correction value of the robot; because the robot does not work on the gravity and does not work on the robot, the current characteristic difference generated by the forward rotation and the reverse rotation of the motor of the driving wheel becomes a factor influencing the difference of the reference walking distance values calculated in different walking directions, and therefore, the reference walking distance value of the robot is converted into standard distance information by setting a distance conversion coefficient multiplied by the reference walking distance value correspondingly, and the rotating speed difference caused by the different rotating directions of the driving wheel of the robot is overcome.

Drawings

Fig. 1 is a flowchart illustrating a method for detecting a walking distance of a robot based on a walking direction according to an embodiment of the present invention.

Fig. 2 is a schematic structural diagram of an intelligent window cleaning machine according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be described in detail below with reference to the accompanying drawings in the embodiments of the present invention. To further illustrate the various embodiments, the present invention provides the accompanying figures. The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the embodiments. With these references, one of ordinary skill in the art will appreciate other possible embodiments and advantages of the present invention.

The window cleaning robot is adsorbed to a vertically arranged glass surface, when the window cleaning robot walks upwards on the glass surface, the window cleaning robot does work on gravity, a driving wheel motor of the window cleaning robot needs to output partial power to overcome the influence of gravity and then can walk upwards, even if the influence of a coded disc installed in a driving wheel is ignored, the window cleaning robot can not continue to walk upwards when the output power of the driving motor is too low, but the mileage information calculated according to a PWM (pulse width modulation) value for controlling the driving motor is still larger than 0, or the actually-traveled distance is smaller than the mileage information calculated according to the PWM value for controlling the driving motor, at the moment, the mileage information calculated according to the PWM value for controlling the driving motor can be converted through a preset distance conversion coefficient, and the distance information under a calibration mode is obtained and comprises the walking distance converted to the opposite direction.

When the window cleaning robot walks downwards on the glass surface, gravity acts on the window cleaning robot, if braking action is not taken, gravity can push the window cleaning robot to accelerate and walk downwards, the phenomenon of skidding easily occurs, the window cleaning robot can continue to walk downwards at the power of the undersize output of the driving motor, the distance actually walked can be greater than the mileage information calculated by the PWM value used for controlling the driving motor, the mileage information calculated by the PWM value used for controlling the driving motor can be converted through the preset set distance conversion coefficient, the distance information under the calibration mode is obtained, and the walking distance in the opposite direction is converted.

Similarly, on the basis of considering the difference of the forward and reverse rotation characteristics of the driving wheels, if the window cleaning robot walks upwards, downwards, leftwards or rightwards on the glass surface, or the floor cleaning robot walks upwards, downwards, leftwards or rightwards on the working surface (including a horizontal ground and a slope), the current characteristics generated by the forward rotation and the reverse rotation of the motor of the driving wheels are different, the torque required by the forward rotation and the reverse rotation of the driving wheels are different, and the time consumed by the forward rotation and the reverse rotation of the driving wheels of the window cleaning robot for passing the same walking distance is different, the mileage information calculated by the PWM value for controlling the driving motor is converted through the preset distance conversion coefficient, so that the distance information under the calibration mode is obtained, and the distance information comprises the walking distance converted to the opposite direction.

As an embodiment, the present embodiment discloses a method for detecting a walking distance by a robot, which is used to reflect the walking distance of the robot on a working surface, and does not necessarily represent an actual distance, and may be a relative distance with respect to a preset starting point; and the detected distance information is represented by electric quantity values and can be in proportional relation with the distance values. The execution main body of the method for detecting the walking distance by the robot is a full-automatic planning mobile robot, and comprises a wheeled robot, a sucker type robot and a crawler type robot, wherein the robots of the type mainly comprise a floor sweeping robot and a window wiping robot, and belong to a cleaning robot with a fan and a driving motor; the robot is provided with driving wheels at two sides, generally, the left side and the right side of a chassis of a machine body are respectively provided with one driving wheel; the robot is internally provided with driving motors electrically connected with the driving wheels, each driving wheel is correspondingly connected with one driving motor, the robot is provided with two driving motors for controlling the rotating speed of the driving wheels so as to control the walking speed of the robot on a working surface, the walking direction of the robot can be controlled by the rotating speed difference value of the two driving wheels, and the driving wheels of the robot can be in contact with the working surface so as to generate friction force capable of hindering the walking of the robot; the robot is also provided with a fan which is used for generating suction to the walking surface of the robot. When the robot is a sweeping robot, a dust suction fan in the sweeping robot is used for sucking dust on a working surface; when the robot is a window cleaning robot, a fan in the window cleaning robot is used for being adsorbed on a working surface; the working surface can be a cleaning medium placed in various postures, and can be a horizontal ground, obliquely arranged glass or a wall surface and the like.

Referring to fig. 1, the method for detecting the walking distance by the robot includes: s1, after the robot enters a walking state from a static state, the robot starts to walk on a working surface and obtains a first PWM (pulse width modulation) value, and then the first PWM value within a specific PWM value range obtained in the walking process of the robot is integrated to determine a reference walking distance value of the robot; then step S2 is performed. In the embodiment, at the starting point position entering the walking state, the robot overcomes the static friction force on the working surface, the driving force generated by the driving motor is greater than the static friction force, the walking speed of the robot is in a direct proportion relation with the first PWM value, the curve of the first PWM value in the body starting time period greater than the preset threshold value is integrated, and the reference walking distance value is obtained through calculation to reflect the distance information traveled by the robot; the larger the reference walking distance value is, the farther the robot walks relative to a preset starting point position; the smaller the reference travel distance value is, the closer the robot travels with respect to a preset starting point position, which is adaptively set according to an expected navigation path or a working area of the robot on the working surface, and is not particularly limited to a fixed position.

In some embodiments, step S1 includes, after the robot enters a walking state from a standstill, setting a real-time measured travel distance value of a code wheel installed on the robot as a reference walking distance value of the robot during walking of the robot on a working surface without integrating a PWM value; then step S2 is performed. The robot is provided with code discs, namely the code discs are arranged in the driving wheels on the left side and the right side, specifically, the photoelectric encoders are arranged on the two sides of the same driving wheel to measure the rotating distance of the driving wheel in real time, and then the robot receives the traveling distance value fed back by the code discs.

It should be noted that, in consideration of the common influence of the forward and reverse rotation of the driving wheels and the gravity on the walking distance of the robot on the working surface mentioned in the background, the step S2 needs to be continued after the step S1 is performed.

And S2, applying a matched distance conversion coefficient to the reference walking distance value of the robot by combining the relation between the walking direction of the robot and the gravity direction, and calculating a walking distance correction value of the robot so as to reflect the relative walking distance of the robot on a working surface, particularly the information of the walking distance at the edge position of the relative working surface. Step S2 is to perform conversion processing on the reference walking distance value of the robot through a preset distance conversion coefficient to obtain distance information in the calibration mode. The specific conversion method comprises the following steps: when the reference walking distance value is configured to be an equivalent distance traveled by the robot in a direction opposite to the current walking direction on the working surface, the step S2 is equivalent to converting the equivalent distance into a distance reached by the robot walking on the working surface for the same time along the current walking direction; or directly converting the reference walking distance value into the distance which is reached by the robot walking on the working surface in the same time in the direction opposite to the current walking direction; the influence of the gravity of the robot on the walking speed of the robot on the working surface and the influence of the positive and negative rotation of the driving wheels on the walking speed of the robot on the working surface are overcome.

In the process of executing the step S1 and the step S2, the robot keeps performing closed-loop adjustment on a PWM value used for controlling the driving motor, and obtains a first PWM value in the process of closed-loop adjustment, the first PWM value obtained in real time forms a PWM value change curve, because the driving force (such as torque force) output by the driving motor is controlled by the first PWM value, and the driving force output by the driving motor is applied to the driving wheel to form the rotation speed of the driving wheel, and further the product of the rotation speed of the driving wheel and the perimeter of the driving wheel is equal to the walking speed of the driving wheel, the walking speed of the robot is in a proportional relation with the first PWM value in a machine body starting time stage larger than a preset threshold value, the first PWM value can be acquired under the condition of barrier-free linear operation, and the proportional parameter of the walking speed of the robot and the first PWM value is related to the type of the driving motor, so that the first PWM value corresponding to the walking speed (the walking speed or the driving force of the driving wheel) of the robot (or can be further converted into a current output by the driving motor). Therefore, the robot walks in the working face placed in various directions, the integral result of the first PWM value adjusted by the closed loop to the time at the output current stabilization stage of the driving motor is calculated by using the first PWM value adjusted by the closed loop, the integral result is used as the distance to be corrected of the robot on the working face, the distance condition of the robot walking is preliminarily reflected, the distance degree of the robot walking relative to the starting point position entering the walking state at the current position is detected, the walking distance of the robot is calculated by using the PWM value used for adjusting the driving wheel, and the cost of a sensor and a mechanical assembly structure can be saved if the mileage data fed back by a code disc is not adopted.

The method comprises the steps that the PWM value can control the rotating speed of the driving motor, the rotating speed of the driving wheel can be changed by the PWM value, the walking speed of the robot is further changed, the course angle of the robot can be specifically adjusted by controlling the relative magnitude of the torque output by the driving motors of the left driving wheel and the right driving wheel, when the rotating speeds of the driving wheels on two sides of the robot are inconsistent, the walking direction of the robot is changed, such as turning, the course angle of the robot is changed, therefore, the absolute value of the angle difference value between the course angle measured in real time by the robot and the target navigation angle can be adjusted to be within a preset angle error range in the closed-loop adjustment process, and the robot can walk along the set direction. Specifically, the robot can adjust a PWM signal for controlling the driving motor through the angle closed-loop feedback adjusting device, apply a first PWM value adjusted in real time to the driving motor, change the output rotating speed of the driving wheel, and then use the course angle of the robot formed by the rotating speed after the driving wheel is changed correspondingly as the feedback input of the angle closed-loop feedback adjusting device to maintain the closed-loop adjustment and indirectly perform the closed-loop adjustment on the course angle measured by the robot in real time.

It should be noted that Pulse Width Modulation (PWM) is an abbreviation of "Pulse Width Modulation" and is abbreviated as Pulse Width Modulation. The PWM value is an average value obtained by adding the conduction time lengths of the switching tubes in one period, the longer the conduction time is, the larger the PWM value acting on the motor is, the larger the average value of direct current output of the switching tubes is, and the rotating speed of the motor can be in direct proportion to the PWM value. The PWM frequency is a ratio of on time to cycle time in a cycle, which is generally called duty ratio, and the more the number of on times, the higher the frequency, therefore, the basic principle of PWM speed regulation control is to turn on and off the power according to a fixed frequency, and change the ratio of on time to off time (duty ratio) in a cycle to change the "duty ratio" of the voltage on the armature of the dc motor according to the need, thereby changing the average voltage, controlling the rotation speed of the motor, and further changing the walking speed of the robot.

As known to those skilled in the art, the power generating components of the wind turbine and the driving motor are electric motors, and preferably, the bridge circuit is a driving circuit structure and controls the forward and reverse rotation of the motor to output the driving current of the motor. The driving motor is an electric motor for controlling the rotation of the driving wheel; the PWM values acting on the left wheel and the right wheel are in a linear relation with the wheel torque force, and the PWM values acting on the fan are mostly the PWM values capable of rotating. The PWM signal input into the motor is a rectangular pulse wave with continuously adjustable pulse width, and the pulse width adjustable pulse power with certain frequency is provided for the motor through a modulator. The larger the pulse width, i.e., the larger the duty ratio, the larger the average voltage supplied to the motor, and the higher the motor speed. Conversely, the smaller the pulse width, the smaller the duty cycle. The smaller the average voltage supplied to the motor, the lower the motor speed. Therefore, the PWM signal is used for controlling the motor to output different analog voltages, so that the motor can reach different output rotating speeds, and the output torque of the motor is also considered to be changed.

The motor speed regulation method comprises the steps that a PWM signal or a PWM value (which can be regarded as being in direct proportion to a duty ratio) which has a function of regulating the motor speed is used, the duty ratio is the ratio of a high level in a period, the larger the ratio of the high level is, the larger the duty ratio is, for a direct current motor, a pin at the output end of the motor can rotate as the high level motor can rotate, when the output end is at the high level, the motor can rotate but speed is increased a little by a little, when the high level suddenly turns to a low level, the motor cannot stop due to the effect of preventing current mutation of the inductance, the original speed can be kept, and therefore the motor speed is reciprocated, the motor speed is the average voltage value output in the period, and can be in a linear relation with the PWM value at a certain operation stage; so essentially, the speed regulation is to make the motor in a state like stop-and-no-stop, full speed-and-no-full speed rotation, and the average speed in one period is the speed regulated by the duty ratio.

As an embodiment, in step S1, before the robot starts to walk, the first PWM value is loaded to the driving motor to control the driving wheel to rotate so as to overcome the static friction force of the working surface until the first PWM value is greater than the preset starting threshold, it is determined that the robot enters the walking state from the standstill state so that the walking speed of the robot is in a linear relationship with the first PWM value obtained in real time, and the robot starts to walk on the working surface so as to overcome the blocking effect of the static friction force from the working surface, wherein the walking speed of the robot is in direct proportion to the first PWM value obtained in real time.

Specifically, before the robot starts to walk at a preset starting point position of the working surface, starting a driving motor from a standstill and receiving control of a first PWM value adjusted in real time, an acceleration direction can be generated, and a relative sliding trend exists relative to the working surface; the fan is also started and is controlled by the second PWM value regulated in real time to be adsorbed on a working surface (particularly a window cleaning robot); the robot has static friction force relative to the contacted working surface until the robot is at the preset starting point position after the preset starting time from the standstill, the driving force provided by the driving motor at the current moment just exceeds the static friction force to overcome the influence of the static friction force, and the robot is determined to finish the body starting and start to walk on the working surface to enter the walking state.

In some embodiments, within the preset starting time, the robot may further perform robot motion calibration disclosed in chinese patent CN111852925B, that is, perform motion calibration on each driving wheel of the robot, strive to complete motion calibration of the left wheel and the right wheel within 210ms, including that the left wheel of the robot is stationary, and the right wheel of the robot performs forward rotation and reverse rotation for a fixed time respectively; the right wheel of the robot is fixed, and the left wheel of the robot respectively carries out forward rotation and reverse rotation for a fixed time; then, the current signal output by the driving motor becomes stable, i.e. enters a linear stage, before which the motion calibration is not considered in this application as the robot walks on the current walking surface.

It should be noted that the preset starting threshold is set as a PWM value required for the driving wheels of the robot to enter the walking state on working surfaces with different friction forces; the arrangement mode of the working face comprises vertical arrangement, horizontal arrangement or inclined arrangement. Under the condition that the medium or position setting mode of the working face changes or the performance of the motor has certain deviation, the actually adjusted first PWM value is basically difficult to be completely consistent with the theoretical PWM value, so that when the later PWM value is compared, the robot can be determined to be in a static state only by obtaining the difference value between the current of the first PWM value and the preset starting threshold value in real time within a deviation threshold value, and otherwise, the robot enters a walking state from the static state.

Preferably, the preset starting threshold value can be set according to a first PWM value required for the robot to normally walk on working surfaces with different friction forces. When the robot normally walks for the robot work, the condition that the suction force of the fan is too large to cause the driving wheel to be motionless or the condition that the suction force of the fan is too small to cause the driving wheel to slip can not occur, and the problem that the driving wheel is motionless or slips can not occur due to the change of the torque force output by the driving motor.

Firstly, the robot is placed on a material with small friction force, and the first PWM value is adjusted up and down, so that the robot can normally walk by utilizing the torque force formed by the control of the first PWM value adjusted by the closed loop. Then the robot is placed on a material with larger friction force, and the first PWM value is finely adjusted, so that the robot can normally walk by utilizing the torque force formed by the control of the first PWM value adjusted by the closed loop; then, verifying whether the robot normally walks according to the current first PWM value on working faces with different friction forces, and if so, setting the first PWM value as the preset starting threshold value; if not, a balance value is found to satisfy most of the conditions encountered by the robot. Due to the great difference of the driving motors, the driving wheels, the die structures and the like of different types of machines, the first PWM values required by the normal walking of the different types of robots are different, so that the first PWM value required by the normal walking of the current robot needs to be obtained in advance. The adjustment of the first PWM value may be achieved by changing said first preset target PWM value in an angle closed loop feedback adjustment means, or by directly changing the first PWM value.

In an embodiment corresponding to the step S1, the method for performing integration processing on the acquired first PWM value within the specific PWM value range includes: after the robot enters the walking state, the robot starts to walk on the working surface from a preset starting point position, different height positions spanning different medium working surfaces or walking on the same working surface in an obstacle-free straight line can be kept, wherein the preset starting point position is the starting point position entering the walking state; the robot samples a first PWM value within preset sampling time, integrates all the first PWM values which are sampled within the preset sampling time and are larger than a preset starting threshold value, and sets an integration result of the first PWM values as a reference walking distance value of the robot; the specific PWM value range refers to a PWM value range which is larger than a preset starting threshold value. Therefore, the integration processing method disclosed in this embodiment may also be regarded as integrating a curve in which the first PWM value within the specific PWM value range is located, and the time interval of the integration is a set of times corresponding to the first PWM value greater than the preset starting threshold; in preset sampling time, the walking speed of the robot is in direct proportion to a first PWM value sampled by the robot, and the preset sampling time is set as time consumed by the robot to walk from a starting position entering the walking state to a current position; if the first PWM values sampled within the preset sampling time are all larger than the preset starting threshold value, the integral time is the preset sampling time, the first PWM values are sampled more comprehensively, more complete integral results are obtained, and more accurate robot walking distance information is fed back.

In the above embodiment, in order to sample the stable first PWM value, the present embodiment preferably sets the preset starting time and the preset sampling time as two adjacent periods of time, and there may be no time interval between the preset starting time and the preset sampling time to ensure that the preset sampling time is a linear period where the robot overcomes the static friction force, that is, the current signal output by the driving motor is in a stable state, so that the walking speed of the robot is in direct proportion to the first PWM value sampled by the robot.

Preferably, in the preset sampling time, the robot configures a timer inside the robot to trigger an interrupt signal every other unit sampling time, and the robot samples the first PWM value once every time the robot detects the interrupt signal, and records the first PWM value as a PWM value at a time in a PWM value curve required by the integration processing; since the rotation speed of the driving motor and the walking speed of the robot can be directly proportional to the first PWM value in the preset sampling time, the first PWM value is used for feeding back the walking speed of the robot in each unit sampling time, and can be recorded as an average speed (represented by an average PWM value in the same period of time) in a period of time or an instantaneous walking speed.

In some embodiments, in order to reduce the unstable current condition when the driving motor starts to rotate, the sampling of the PWM value required for the integration process is located in the second half of a fixed time 360ms, so as to use the stable current and reduce the error, for example, the preset starting time is equal to 210ms, the preset sampling time is equal to 100ms, the preset sampling time is delayed from the preset starting time, the sampling is started from 210ms and is stopped until 310ms, and the sampling time lasts for 100 ms; therefore, the robot can finish overcoming the static friction force and calculating the PWM value sampling required by the reference walking distance value in a short time, so that the practicability of the robot is stronger.

As an embodiment, the method for calculating the travel distance correction value of the robot by applying a corresponding distance conversion coefficient to the reference travel distance value of the robot in combination with the relationship between the travel direction of the robot and the gravity direction includes:

the robot measures the walking direction of the robot on the working surface in real time through a gyroscope, and determines the position and posture relation between the walking direction of the robot and the gravity direction so as to determine the acting condition of gravity on the robot walking on the working surface; the robot detects angle variation generated by the robot from a preset starting point position by using a gyroscope, wherein the angle variation comprises angle variation of a course angle of the robot, angle variation of a pitch angle and angle variation of a roll angle, and is used for representing variation of the walking direction of the robot, and particularly representing variation of the walking direction of the robot on a working surface. Wherein, the position appearance relation between the walking direction of robot and the direction of gravity includes: under the condition that the walking direction of the robot is not vertical to the gravity direction, when the walking direction of the robot is deviated upwards relative to the gravity direction, the robot walking on the working surface does work on the gravity of the robot, so that the gravity can cause walking obstruction effect on the robot in the walking process of the robot; when the walking direction of the robot is inclined downwards relative to the gravity direction, the gravity acts on the robot walking on the working surface, so that the gravity brings walking acceleration effect to the robot in the walking process of the robot. The steering of the drive wheels in the case where the traveling direction of the robot is deviated upward with respect to the direction of gravity is different from the steering of the drive wheels in the case where the traveling direction of the robot is deviated downward with respect to the direction of gravity.

When the traveling direction of the robot is perpendicular to the direction of gravity, no matter whether the traveling direction of the robot is deviated to the left or the right with respect to the direction of gravity, gravity does not apply work to the robot traveling on the work surface, the robot traveling on the work surface does not apply work to the gravity thereof, and the steering of the drive wheels when the traveling direction of the robot is deviated to the left with respect to the direction of gravity is different from the steering of the drive wheels when the traveling direction of the robot is deviated to the right with respect to the direction of gravity.

In this embodiment, the robot measures the walking direction of the robot on the working surface through the gyroscope, specifically, the robot can combine acceleration information provided by the accelerometer to form pose information of the robot, then perform pose calculation through a coordinate system, acquire a heading angle, a pitch angle and a roll angle of the robot, and further determine a pose relationship between the walking direction of the robot and the gravity direction, including an angle relationship between the walking direction of the robot and the gravity acceleration direction. The specific pose or angle resolving mode is a conventional trigonometric function operation, and various conversion modes can exist according to the definition of the pitch angle and the roll angle, and are not described in detail herein.

It should be noted that the robot can travel on the work surface through various combinations of real-time variation with respect to three mutually perpendicular axes defined by the body, these three perpendicular axes including: a front-rear axis, a lateral axis and a central vertical axis; the direction of travel along the front-rear axis is denoted as the front side, as the head (forward end) of the robot; the backward driving direction along the front-rear axis is denoted as the rear side as the tail (backward end) of the robot; the direction of the lateral axis is substantially along the line connecting the centers of the rotation axes of the left and right driving wheels.

When the robot climbs a vertical or inclined working surface, the forward part of the robot inclines upwards, the backward part of the robot inclines downwards, and the robot is regarded as upward facing, so that the body of the robot is in contact with the surface of the working surface at a certain inclination angle, the robot is in a facing-up state, and when the inclination degree of the working surface is increased, the pitch angle of the robot measured by a gyroscope is gradually increased to 90 degrees in the walking process of the robot; when the pitch angle of the robot measured by the gyroscope is between 0 degree and 90 degrees but does not reach 90 degrees, the walking direction of the robot is not perpendicular to the gravity direction; when the pitch angle of the robot reaches 90 degrees, the walking direction of the robot can be considered to be perpendicular to the gravity direction.

When the robot descends along an obliquely arranged working surface, the backward part of the robot body inclines upwards, the forward part of the robot body inclines downwards, and the robot body is regarded as downward-pitching, so that the robot body is in contact with the surface of the working surface at a certain inclination angle, and the pitch angle of the robot measured by the gyroscope is not 0; when the robot is in a overlook state, when the inclination degree of a working surface is larger, the pitch angle of the robot measured by the gyroscope is gradually reduced to-90 degrees in the walking process of the robot; when the pitch angle of the robot measured by the gyroscope is between 0 degree and-90 degrees but does not reach-90 degrees, the walking direction of the robot can be regarded as not perpendicular to the gravity direction; when the pitch angle of the robot reaches-90 degrees, the walking direction of the robot can be considered to be vertical to the gravity direction.

In addition, the robot may be rotatable about a central vertical axis. When the robot travels in the forward direction, when the robot turns to the right side of the front-rear axis, it turns "right", and when the robot turns to the left side of the front-rear axis, it turns "left".

After the pose relation between the walking direction and the gravity direction of the robot is determined, when the robot detects that the walking direction of the robot is not perpendicular to the gravity direction, if the walking direction of the robot is arranged upwards relative to a horizontal plane, the robot is determined to walk upwards on a working surface relative to the horizontal plane, the currently calculated reference walking distance value of the step S2 is controlled to be multiplied by a first distance conversion coefficient, and then the product of the reference walking distance value and the first distance conversion coefficient is marked as a walking distance correction value of the robot. When the walking direction of the robot is determined to be not vertical to the gravity direction, if the walking direction of the robot is set downwards relative to the horizontal plane, the robot is determined to walk downwards on the working surface relative to the horizontal plane, the reference walking distance value calculated currently in the step S2 is controlled to be multiplied by a second distance conversion coefficient, and then the product of the reference walking distance value and the second distance conversion coefficient is marked as a walking distance correction value of the robot; wherein the working surface is not arranged parallel to the horizontal plane; the direction of gravity is vertically downward. The working face can be inclined to the horizontal plane or vertically arranged on the horizontal plane, and comprises but is not limited to a glass plate which is obliquely arranged and a wall surface which is vertical to the horizontal ground. The gravity direction of the robot is vertically downward and is kept perpendicular to the horizontal plane, and the gravity direction is direction information obtained in advance.

Specifically, when the robot walks upwards on a working surface relative to a horizontal surface, the walking direction of the robot is set to be a first preset inclined direction; when the robot walks downwards on the working surface relative to the horizontal surface, the walking direction of the robot is set to be a second preset inclined direction; the angle information corresponding to the first preset inclination direction and the angle information corresponding to the second preset inclination direction can be obtained by resolving the angle measured by the gyroscope. On the same working surface, the first distance conversion coefficient and the second distance conversion coefficient are reciprocal. When the first preset inclination direction and the second preset inclination direction are symmetrical, the first preset inclination direction and the second preset inclination direction point to opposite directions respectively. The time spent by the robot walking in the first preset inclined direction through the first preset reference distance value is marked as upward test time, and the time spent by the robot walking in the second preset inclined direction through the first preset reference distance value is marked as downward test time; preferably, the robot is controlled to record the walking time of the robot from a preset starting point position on a working surface with a boundary, the robot walks upwards to the uppermost boundary and then linearly walks from the uppermost boundary to the lowermost boundary of the same working surface, and the time consumed by the robot to linearly walk from the uppermost boundary to the lowermost boundary of the same working surface is recorded as downward test time; then, the robot records the time consumed by the robot to travel from the boundary at the lowermost end of the working surface to the boundary at the uppermost end of the same working surface as upward test time; the distance that the robot walks in a straight line between the uppermost boundary and the lowermost boundary of the same working surface is fixed, the distance between the uppermost boundary and the lowermost boundary of the same working surface is represented by using a first preset reference distance value, and the reference walking distance value, the first preset reference distance value and the walking distance correction value disclosed by the application all use the same dimension, and specifically can be the dimension of the time integration result of a PWM value; of course, the relative positions of the uppermost boundary and the lowermost boundary of the same working surface are also fixed.

As a first conversion embodiment, on the premise that the robot sets the ratio of the downward test time to the upward test time as a first distance conversion coefficient, when the robot travels on the working surface in a first preset inclined direction, the robot travels upward on the working surface relative to the horizontal plane, and the travel distance correction value of the robot calculated in step S2 is smaller than the reference travel distance value, so that the travel distance correction value capable of introducing the influence of the gravity and the travel distance difference caused by the forward and reverse rotation of the driving wheels is obtained by the first distance conversion coefficient; because the gravity causes a walking acceleration effect on the robot in the process that the robot walks downwards, the gravity causes a walking hindering effect on the robot in the process that the robot walks upwards, and the gravity effect is dominant relative to the walking distance difference caused by positive and negative rotation of the driving wheels, therefore, the downward test time is shorter than the upward test time, the first distance conversion coefficient is set to be smaller than a value 1, the currently converted distance value is smaller than a reference walking distance value obtained by integral processing in the upward walking process, and the walking distance correction value of the robot calculated in the step S2 introduces the hindering effect of the gravity of the robot on the walking of the working face and the walking distance difference caused by the positive and negative rotation of the driving wheels, so that the walking distance correction value of the robot calculated in the step S2 is smaller than the reference walking distance value (influenced by the torsion applied to the driving wheels) obtained by the integral processing of the first PWM value. Specifically, in the process that the robot travels upwards along a vertically arranged working face or travels upwards along an obliquely arranged working face, the gravity action is dominant relative to the travel distance difference caused by positive and negative rotation of a driving wheel, and is hindered by the gravity of the robot, namely the gravity acceleration acts on the reduction of the travel speed of the robot in proportion to a first PWM value, under the control of the first PWM value sampled by the robot, the travel speed of the robot (obtained by multiplying the real-time rotating speed of the driving motor by the perimeter of the driving wheel) formed by the output current conversion of the driving motor is greater than the actual travel speed of the robot in the working face, the distance which plays a role of correction needs to be converted by the first distance conversion coefficient which is less than the value 1, and the distance is used for representing the correction value of the distance traveled upwards, namely the travel distance correction value of the robot, so that the weakening effect of the gravity acceleration on the travel speed output by the motor (the distance calculated by integrating the PWM value is greater than the actual travel distance) is compensated by reducing the reference travel distance value, and the information of the relative distance traveled actually by the robot which is traveled upwards.

As a second conversion embodiment, on the premise that the ratio of the downward test time to the upward test time is set as a second distance conversion coefficient by the robot, when the robot travels in a second preset inclined direction on the working surface, the robot travels downward relative to the horizontal plane on the working surface, and the travel distance correction value of the robot calculated in step S2 is smaller than the reference travel distance value, so as to convert the reference travel distance value of the robot into a distance which is reached by the same time that the robot travels upward relative to the horizontal plane on the working surface for the same time, where the same time is the time consumed by the robot to travel downward relative to the horizontal plane to the current position on the working surface from the preset starting point position; because the gravity causes a walking acceleration effect on the robot in the process that the robot walks downwards, the gravity causes a walking hindering effect on the robot in the process that the robot walks upwards, and the influence exerted by the gravity on the walking speed is dominant relative to the walking distance difference caused by the positive and negative rotation of the driving wheels, so that the downward test time is less than the upward test time, the second distance conversion coefficient is set to be less than the value 1, and the walking distance correction value of the robot calculated in the step S2 is less than the reference walking distance value, therefore, the setting of the second distance conversion coefficient disclosed in the embodiment weakens the influence of the gravity of the robot on the acceleration effect of the downward walking of the robot on the working face and the walking distance difference caused by the positive and negative rotation of the driving wheels, and facilitates the comparison of the walking distance correction value of the robot with the reference walking distance value calculated by the step S1 in the process that the robot actually walks upwards on the working face relative to the horizontal plane, and a distance standard of the opposite phase in the same walking direction exists to convert the distance standard into a distance which identifies the robot walking in the first preset oblique direction.

As a third conversion embodiment, on the premise that the robot sets the ratio of the upward test time to the downward test time as the first distance conversion coefficient, when the robot travels on the working surface in the first preset inclined direction, the robot travels upward on the working surface relative to the horizontal plane, and the travel distance correction value of the robot is calculated to be greater than the reference travel distance value, so as to convert the reference travel distance value of the robot into a distance reached by the robot traveling downward on the working surface relative to the horizontal plane at the same time, where the same time in this embodiment is the time taken for the robot to travel upward on the working surface relative to the horizontal plane from the preset starting point position to the current position. In this embodiment, since the gravity acts on the robot to accelerate the robot when the robot travels downward, the gravity acts on the robot to hinder the robot from traveling when the robot travels upward, and an influence exerted by the gravity on the traveling speed is dominant over a traveling distance difference caused by forward and reverse rotation of the driving wheels, so that the downward test time is longer than the upward test time, the first distance conversion coefficient is set to be larger than a value 1, and the traveling distance correction value of the robot calculated in step S2 is larger than a reference traveling distance value, and thus the setting of the first distance conversion coefficient disclosed in this embodiment weakens the hindering effect of the gravity of the robot on downward traveling of the working surface and the traveling distance difference influence caused by forward and reverse rotation of the driving wheels, so that the traveling distance correction value of the robot is compared with the reference traveling distance value calculated in step S1 when the robot actually travels downward of the working surface relative to the horizontal surface, that there is a comparison distance standard in the same traveling direction, and the comparison can be uniformly converted into a distance standard in which the distance traveled by the robot in the second preset oblique direction is too far and near.

In some embodiments, the drive wheel is forward when the robot is walking along a first predetermined incline direction on the work surface; when the robot walks along a second preset inclined direction on the working surface, the driving wheels are reversely rotated; because torsion required by forward and reverse rotation of the driving wheel is different and currents correspondingly output by the driving motor are different, real-time rotating speeds generated by the forward and reverse rotation are different, so that the distance traversed by the robot when the robot travels along the first preset inclined direction for a fixed time on the working surface is different from the distance traversed by the robot when the robot travels along the second preset inclined direction on the working surface for the same time, the traveling distance difference caused by the forward and reverse rotation of the driving wheel is caused, and the larger distance difference (the interference of gravity acceleration on the traveling speeds in different directions) can be caused by combining the gravity action of the robot. In particular, when the driving wheel is changed from the forward rotation to the reverse rotation, the first PWM value may be changed from a positive value to a negative value, and the first PWM value controls the driving wheel to rotate in the forward rotation in a state of the positive value.

As a fourth conversion embodiment, on the premise that the robot sets the ratio of the upward test time to the downward test time as a second distance conversion coefficient, when the robot travels in a second preset inclined direction on the working surface, the robot travels downward on the working surface relative to the horizontal plane, and the calculated travel distance correction value of the robot is greater than the reference travel distance value, so that the travel distance correction value capable of introducing the influence of gravity and the travel distance difference caused by the forward and reverse rotation of the driving wheels is converted by the second distance conversion coefficient; because the gravity causes a walking acceleration effect on the robot in the process that the robot walks downwards, the gravity causes a walking hindering effect on the robot in the process that the robot walks upwards, and the influence exerted by the gravity on the walking speed is dominant relative to the walking distance difference caused by positive and negative rotation of the driving wheels, therefore, the downward testing time is shorter than the upward testing time, and the second distance conversion coefficient is set to be larger than a value 1, so that the distance value obtained by conversion is larger than the reference walking distance value obtained by integral processing in the upward walking process, and the acceleration effect of the gravity of the robot on the walking of the robot on the working surface is introduced into the walking distance correction value of the robot calculated in the step S2, so that the walking distance correction value of the robot calculated in the step S2 is larger than the reference walking distance value obtained by integral processing of the first PWM value (influenced by the torsion applied to the driving wheels). Specifically, in the process that the robot travels downwards along a vertically arranged working surface or travels downwards along an obliquely arranged working surface, the robot is hindered by the gravity of the robot, that is, the acceleration of the gravity enhances the traveling speed of the robot in direct proportion to a first PWM value, under the control of the first PWM value sampled by the robot, the traveling speed of the robot (obtained by multiplying the real-time rotating speed of the driving motor by the perimeter of the driving wheel) formed by converting the output current of the driving motor is smaller than the actual traveling speed of the robot in the working surface, the distance having the correction function needs to be converted by the second distance conversion coefficient larger than the value 1, and the distance is used to represent the corrected value of the distance traveled upwards, that is, the traveling distance corrected value larger than the reference traveling distance value, so that the acceleration of the traveling speed output by the gravity to the motor (the distance calculated by integrating the PWM value is smaller than the actual traveling distance) is compensated by increasing the reference traveling distance value, and the information of the relative distance actually traveled downwards by the robot in the working surface is restored.

In the four conversion embodiments, the first distance conversion coefficient and the second distance conversion coefficient are not changed by the change of the medium of the working surface contacted by the same type of robot; both the first distance conversion coefficient and the second distance conversion coefficient vary with the type of the robot. The first preset inclination direction and the second preset inclination direction are symmetrical, so that the upward test time and the downward test time can be measured in the same walking path or a parallel path, the difference between the upward test time and the downward test time is greatly influenced by the gravity acceleration, and the influence exerted by the difference between the forward rotation and the reverse rotation of the driving wheel is reduced; on the same working surface, the first distance conversion coefficient and the second distance conversion coefficient are reciprocal. The robot walks to the boundary of the uppermost end of the working surface in a straight line from the boundary of the lowermost end of the working surface along a first preset inclined direction, and the consumed time is upward test time; the robot starts from the boundary of the uppermost end of the working surface along the second preset inclined direction, and travels to the boundary of the lowermost end of the working surface in a straight line, and the consumed time is downward test time.

In summary, in order to obtain a walking distance correction value capable of introducing the influence of gravity action and the influence of walking distance difference caused by positive and negative rotation of the driving wheel through the first distance conversion coefficient, the reference walking distance value is reduced to compensate the weakening effect of gravity acceleration on the walking speed output by the motor (the distance calculated by integrating the PWM value is larger than the actually-walking distance), the currently-calculated reference walking distance value is controlled to be multiplied by the first distance conversion coefficient with the numerical value smaller than 1, the walking distance correction value of the robot is determined, standard distance information introducing the influence of gravity action and the influence of walking distance difference caused by positive and negative rotation of the driving wheel is formed, and the relative distance information actually-walking of the robot on the working face is restored to a certain extent.

In order to weaken the acceleration effect of the gravity of the robot on the downward walking of the robot on the working surface and the influence of the walking distance difference caused by different rotating directions of the driving wheels, the currently calculated reference walking distance value is controlled to be multiplied by a second distance conversion coefficient with the numerical value smaller than 1, the walking distance correction value of the robot is determined, the reference walking distance value obtained by the integration processing of the robot in the second pre-inclined direction is converted into the distance which is reached by the same time when the robot walks on the working surface upwards relative to the horizontal plane, and the distance is converted into standard distance information which is used for comparing the distance traveled by the robot in the first pre-inclined direction.

In order to weaken the effect of the gravity of the robot on the barrier effect of the robot on the upward walking of the working face and the influence of the walking distance difference caused by different rotating directions of the driving wheels, the currently calculated reference walking distance value is controlled to be multiplied by a first distance conversion coefficient with the numerical value larger than 1, the walking distance correction value of the robot is determined, the reference walking distance value obtained by the integration processing of the robot in the first pre-inclined direction is converted into the distance which is reached by the same time when the robot walks downwards on the working face relative to the horizontal face, and the distance is converted into standard distance information which is used for comparing the distance traveled by the robot in the second pre-inclined direction.

In order to obtain a walking distance correction value capable of introducing the influence of gravity action and the influence of walking distance difference caused by positive and negative rotation of a driving wheel through a second distance conversion coefficient, a reference walking distance value is increased to compensate the acceleration action of gravity acceleration on the walking speed output by a motor (the distance calculated by integrating a PWM (pulse width modulation) value is larger than the actually walking distance), the currently calculated reference walking distance value is controlled to be multiplied by the second distance conversion coefficient with the numerical value larger than 1, the walking distance correction value of the robot is determined, standard distance information introducing the influence of gravity action and the influence of walking distance difference caused by positive and negative rotation of the driving wheel is formed, and the relative distance information actually walking downwards on a working face of the robot is restored to a certain extent.

Therefore, a matching distance conversion coefficient is applied to the reference walking distance value of the robot; if the robot walks upwards along the vertically arranged working face or upwards along the obliquely arranged working face, controlling the currently calculated reference walking distance value to be multiplied by a first distance conversion coefficient, determining a walking distance correction value of the robot, and obtaining standard distance information; or if the robot walks downwards along the vertically arranged working face or downwards along the obliquely arranged working face, the currently calculated reference walking distance value is controlled to be multiplied by the second distance conversion coefficient, the walking distance correction value of the robot is determined, and standard distance information is obtained. The influence of the gravity of the robot on the walking of the robot on the current walking surface and the rotation speed difference caused by the difference of the rotation directions of the driving wheels of the robot are overcome, the corrected value of the distance traveled upwards can be represented by the distance information traveled downwards, and the influence exerted by the gravity influence and the difference caused by the positive and negative rotation of the driving wheels is inhibited for the path planning of the robot in the vertical upward direction or the inclined upward direction; the corrected value of the distance traveled downwards can be represented by the distance traveled upwards, and the influence of gravity and the influence of difference caused by positive and negative rotation of the driving wheels can be restrained for planning the path of the robot in the vertical downwards direction or the inclined downwards direction.

As an embodiment, the method for calculating the travel distance correction value of the robot by applying the corresponding distance conversion coefficient to the reference travel distance value of the robot in combination with the relationship between the travel direction of the robot and the gravity direction further includes:

when the walking direction of the robot is perpendicular to the gravity direction, if the walking direction of the robot is a first preset horizontal direction perpendicular to the gravity direction, the robot is determined to walk on the working surface along the first preset horizontal direction, the robot does not work on the gravity in the walking process, and the gravity does not work on the robot, the currently calculated reference walking distance value is controlled to be multiplied by a third distance conversion coefficient, the product of the reference walking distance value and the third distance conversion coefficient is marked as the walking distance correction value of the robot, the walking distance correction value of the robot is determined, and the walking distance correction value can be reflected as the distance far and near condition that the current position of the robot walks relative to a preset starting point position of the working surface. When the walking direction of the robot is vertical to the gravity direction, if the walking direction of the robot is a second preset horizontal direction vertical to the gravity direction, controlling the currently calculated reference walking distance value to be multiplied by a fourth distance conversion coefficient, and marking the product of the reference walking distance value and the fourth distance conversion coefficient as a walking distance correction value of the robot, wherein the walking distance correction value can be reflected as the distance traveled by the current position of the robot relative to a preset starting point position of a working surface; wherein the starting point position for entering the walking state is the preset starting point position. Because the robot does not work on the gravity and does not work on the robot, the current characteristic difference generated by the forward rotation and the reverse rotation of the motor of the driving wheel becomes an influence factor of the difference of the currently calculated reference walking distance value in different walking directions of the same walking area; therefore, the difference of the rotating speed caused by the different rotating directions of the driving wheels of the robot is overcome by setting the distance conversion coefficient correspondingly multiplied by the reference walking distance value.

In this embodiment, when the working surface is parallel to the horizontal plane, an included angle formed between the second preset horizontal direction and the first preset horizontal direction on the working surface is greater than 90 degrees, and the second preset horizontal direction and the first preset horizontal direction respectively point to two sides of the robot; when the working surface is not parallel to the horizontal plane, the included angle formed between the second preset horizontal direction and the first preset horizontal direction on the working surface is 180 degrees. Preferably, the working surface can be arranged obliquely to the horizontal plane, can be vertically arranged on the horizontal plane, and can also be a horizontal ground; work surfaces include, but are not limited to, obliquely positioned glass panels, wall surfaces vertical to a horizontal floor, and horizontal floors. The gravity direction of the robot is vertically downward, and the direction information is obtained in advance by keeping the direction information vertical to the horizontal plane. The walking direction of the robot is obtained by calculating the angle measured by the gyroscope according to the embodiment, and the pose relationship between the walking direction of the robot and the gravity direction, including the angle relationship between the walking direction of the robot and the gravity direction, is determined.

Specifically, in the process that the robot walks in the horizontal direction along a vertically arranged working face, or walks in the horizontal direction along an obliquely arranged working face, or walks along a working face arranged in parallel with the horizontal plane, the first preset horizontal direction points to one side of the working face, and the second preset horizontal direction points to the other side of the working face. And on the same working surface, the third distance conversion coefficient and the fourth distance conversion coefficient are reciprocal. When the first preset inclination direction and the second preset inclination direction are symmetrical, the first preset inclination direction and the second preset inclination direction respectively point to opposite directions, and for the same horizontal plane, for example, when the first preset horizontal direction is set to point to the right side of the working surface, the second preset horizontal direction is set to point to the left side of the working surface.

In order to obtain the third distance conversion coefficient and the fourth distance conversion coefficient, the calculation method in this embodiment is that the time consumed by the robot to travel the second preset reference distance along the first preset horizontal direction is marked as the first test time, and the time consumed by the robot to travel the second preset reference distance along the second preset horizontal direction is marked as the second test time; then the robot sets the ratio of the first test time to the second test time as a third distance conversion coefficient; or the robot sets the ratio of the second test time to the first test time as a third distance conversion coefficient, wherein the third distance conversion coefficient and the fourth distance conversion coefficient are reciprocal on the same working surface. Preferably, the robot is controlled to record the walking time of the robot from a preset starting point position on a working face with a boundary, the robot walks leftwards to the leftmost boundary and then walks straightly to the rightmost boundary of the same working face from the leftmost boundary of the working face, and the time spent by the robot to walk straightly to the rightmost boundary of the same working face from the leftmost boundary of the working face is recorded as a first test time; then, the robot records the time consumed by the robot to linearly walk from the boundary at the rightmost side of the working surface to the boundary at the leftmost side of the same working surface as second test time; the distance that the robot walks in a straight line between the leftmost boundary and the rightmost boundary of the same working face is fixed, the distance between the leftmost boundary and the rightmost boundary of the same working face is represented by a second preset reference distance value, the reference walking distance value, the second preset reference distance value and the walking distance correction value disclosed by the application all use the same dimension, and specifically can be the dimension of the time integration result of a PWM value; of course, the relative position between the leftmost boundary and the rightmost boundary of the same work surface is also fixed.

As a fifth conversion embodiment, on the premise that the ratio of the second test time to the first test time is set as the third distance conversion coefficient by the robot, when the robot travels on the working surface along the first preset horizontal direction, gravity does not cause an acceleration effect or an obstruction effect on the robot, because the current characteristics generated by the forward rotation and the reverse rotation of the motor of the driving wheel are different, the torque required by the forward rotation and the reverse rotation of the driving wheel are different, and the time consumed by the forward rotation and the reverse rotation of the driving wheel of the robot for passing through the same distance is different, so the third distance conversion coefficient is not equal to the value 1, the travel distance of the robot calculated in step S2 is not equal to the reference travel distance correction value, the travel distance correction value of the robot calculated in step S2 is equivalent to the travel time consumed by the robot for traveling on the working surface along the first preset horizontal direction to travel the driving wheel for passing through the same time on the working surface along the second preset horizontal direction, the same time is the time that the robot travels on the working surface along the first preset horizontal direction from the preset starting point position, the travel time of the driving wheel for traveling on the working surface along the first preset horizontal direction, the driving wheel is different from the required travel speed, and the PWM control may be formed along the second preset horizontal direction that the robot may be different from the turning direction required by the turning direction that the robot for traveling of the first horizontal direction. Therefore, a third distance conversion coefficient is introduced to convert the reference walking distance calculated in the step S2 into a new walking direction to represent, and the walking distance difference caused by positive and negative rotation of the driving wheel is overcome, so that the walking distance correction value of the robot calculated in the step S2 can reflect the distance traveled by the robot relative to the preset starting point more than the reference walking distance value (influenced by the torsion applied to the driving wheel) obtained by integrating the first PWM value.

As a sixth conversion embodiment, on the premise that the robot sets the ratio of the second test time to the first test time as the fourth distance conversion coefficient, when the robot travels on the working surface along the second preset horizontal direction, the travel distance correction value of the robot calculated in step S2 is used to convert the reference travel distance value of the robot into the distance reached by the robot traveling on the working surface along the first preset horizontal direction for the same time, where the same time is the time consumed by the robot traveling on the working surface along the second preset horizontal direction from the preset starting point position to the current position; because the current characteristics generated by the forward rotation and the reverse rotation of the motor of the driving wheel are different, the torque required by the forward rotation and the reverse rotation of the driving wheel is different, and the time consumed by the forward rotation and the reverse rotation of the driving wheel of the robot for passing the same distance is different, the fourth distance conversion coefficient is not equal to the value 1, and the walking distance correction value of the robot calculated in the step S2 is not equal to the reference walking distance value, the setting of the second distance conversion coefficient disclosed in the embodiment is convenient for the walking distance correction value of the robot to be compared with the reference walking distance value calculated in the step S1 in the process that the robot actually walks upwards on the working surface relative to the horizontal surface, and a comparison distance standard is formed in the same walking direction to convert the comparison distance standard into the distance which the robot travels in the first preset horizontal direction, so that the influence of the walking distance difference caused by the forward rotation and the reverse rotation of the driving wheel is weakened.

As a seventh conversion embodiment, on the premise that the robot sets the ratio of the first test time to the second test time as the fourth distance conversion coefficient, when the robot travels on the working surface along the second preset horizontal direction, gravity does not cause an acceleration effect or an obstruction effect on the robot, because the current characteristics generated by the forward rotation and the reverse rotation of the motor of the driving wheel are different, the torques required by the forward rotation and the reverse rotation of the driving wheel are different, and the time consumed by the forward rotation and the reverse rotation of the driving wheel of the robot for the same distance is different, the third distance conversion coefficient is not equal to the value 1, the travel distance correction value of the robot calculated in step S2 is not equal to the reference travel distance value, the travel distance correction value of the robot calculated in step S2 is equivalent to the travel speed of the robot corresponding to the travel of the robot on the working surface along the second preset horizontal direction, so as to travel the robot on the working surface along the first preset horizontal direction, and the travel speed required by the robot for the travel along the second preset horizontal direction is different from the preset start position, and the PWM control of the robot for the travel direction for the robot along the first preset horizontal direction is possible. Therefore, a fourth distance conversion coefficient is introduced to convert the reference walking distance calculated in the step S2 into a new walking direction to represent, and the walking distance difference caused by positive and negative rotation of the driving wheel is overcome, so that the walking distance correction value of the robot calculated in the step S2 can reflect the distance traveled by the robot relative to the preset starting point more than the reference walking distance value (influenced by the torsion applied to the driving wheel) obtained by integrating the first PWM value.

As an eighth conversion embodiment, on the premise that the robot sets the ratio of the first test time to the second test time as the third distance conversion coefficient, when the robot travels on the working surface along the first preset horizontal direction, the travel distance correction value of the robot calculated in step S2 is used to convert the reference travel distance value of the robot into the distance reached by the robot traveling on the working surface along the second preset horizontal direction for the same time, where the same time is the time consumed by the robot traveling on the working surface from the preset starting point position to the current position along the first preset horizontal direction; because the current characteristics generated by the forward rotation and the reverse rotation of the motor of the driving wheel are different, the torque required by the forward rotation and the reverse rotation of the driving wheel is different, and the time consumed by the forward rotation and the reverse rotation of the driving wheel of the robot for passing the same distance is different, therefore, the third distance conversion coefficient is not equal to the value 1, and the walking distance correction value of the robot calculated in the step S2 is not equal to the reference walking distance value, the setting of the first distance conversion coefficient disclosed in the embodiment is convenient for the walking distance correction value of the robot to be directly compared with the reference walking distance value calculated in the step S1 in the process that the robot actually walks along the second preset horizontal direction on the working surface, and a comparison distance standard is formed in the same walking direction to convert the comparison into the distance of the walking distance which the robot travels in the second preset horizontal direction, so that the influence of the walking distance difference caused by the forward rotation and the reverse rotation of the driving wheel is weakened.

In the foregoing embodiment, for the difference in the traveling distance caused by the forward and reverse rotation of the driving wheels, it is preferable that the driving wheels are rotated forward when the robot travels in the first preset horizontal direction on the work surface; when the robot walks along the second preset horizontal direction on the working surface, the driving wheels can rotate reversely; because torque force required by forward and reverse rotation of the driving wheel is different and currents correspondingly output by the driving motor are different, real-time rotating speeds generated by forward and reverse rotation are different, the distance traversed by the robot when the robot walks along the first preset horizontal direction for a fixed time on the working face is different from the distance traversed by the robot when the robot walks along the second preset horizontal direction for the same time on the working face, and the walking distance difference caused by forward and reverse rotation of the driving wheel is caused. The distance conversion method applies a matched distance conversion coefficient to a reference walking distance value of the robot, and the disclosed third distance conversion coefficient is used for overcoming the rotating speed difference caused by different rotating directions of driving wheels of the robot; the fourth distance conversion coefficient is used for overcoming the rotating speed difference caused by different rotating directions of the driving wheels of the robot; the third distance conversion coefficient and the fourth distance conversion coefficient are not changed due to the change of the medium of the working surface contacted by the same type of robot; the third distance conversion coefficient and the fourth distance conversion coefficient both vary with the type of the robot.

In summary, if the robot walks in the horizontal direction along a vertically arranged working surface, or walks in the horizontal direction along an obliquely arranged working surface, or walks along a working surface arranged in parallel with the horizontal plane, the currently calculated reference walking distance value is controlled to be multiplied by the corresponding distance conversion coefficient, and the walking distance correction value of the robot is determined; because the robot does not work on the gravity and does not work on the robot, the current characteristic difference generated by the positive rotation and the negative rotation of the motor of the driving wheel becomes a factor influencing the difference of the reference walking distance values calculated in different walking directions, therefore, the reference walking distance value of the robot is converted into standard distance information by setting a distance conversion coefficient multiplied by the reference walking distance value correspondingly, and the rotating speed difference caused by the different rotating directions of the driving wheel of the robot is overcome.

In some embodiments, whether the walking direction of the robot is perpendicular to the gravity direction or not, if the working surface is parallel to the gravity direction, the robot needs to be configured to be attached to the working surface, wherein the working surface may be a wall surface or a surface of a glass window, the robot needs to be attached to the working surface first, and then walk on the working surface along a predetermined direction, such as a window cleaning robot; when the robot walks on the working surface, the driving wheels of the robot are allowed to rotate forwards or backwards on the working surface so as to adapt to the change of the walking direction of the robot on the working surface. In addition, regardless of whether the walking direction of the robot is perpendicular to the gravity direction, if the working plane is perpendicular to the gravity direction, the working plane is regarded as a horizontal plane, for example, a horizontal ground, and the working plane abuts against the driving wheels of the robot.

Preferably, in addition to the action of gravity, the driving wheels of the robot are in contact with the working surface during the walking of the robot on the working surface so as to enable the robot to bear the friction force from the working surface; when the robot walks upwards or downwards on a working surface relative to a horizontal plane, the friction force born by the robot is smaller external resistance relative to the gravity of the robot, and even does not occupy a dominant factor when the walking speed of the robot is influenced. When the medium of the working surface contacted by the robot changes, the friction force correspondingly born by the robot on the working surface changes, but the same type of robot is not influenced to execute the method for detecting the walking distance by the robot so as to obtain the walking distance correction value of the robot.

As an embodiment, the method of closed-loop adjusting a PWM value for controlling a driving motor includes:

under the condition that the absolute value of the angle difference value between the course angle measured by the robot in real time and the target navigation angle in the current regulation period is not within the preset angle error range, carrying out PID regulation on the PWM value for controlling the driving motor by the robot, in the process of carrying out PID regulation on the PWM value for controlling the driving motor, taking the difference value between the PWM value for controlling the driving motor and the first preset target PWM value in the current regulation period as the feedback input of the next regulation period so as to reduce the difference value between the PWM value for controlling the driving motor and the first preset target PWM value, setting the PWM value for controlling the driving motor as the first PWM value, and then inputting the first PWM value into the driving motor on the corresponding side in real time to obtain the driving wheel current sampling value output by the driving motor on the side, wherein after the robot enters the walking state, the real-time rotating speed of the driving motor is in direct proportion to the first PWM value; for the driving motors correspondingly connected with the driving wheels arranged on each side of the robot, when the PWM value used for controlling the driving motors on the corresponding side and the first preset target PWM value are smaller than the steady-state error of the corresponding preset driving wheels, the robot adjusts the walking direction based on the difference value of the real-time rotating speeds of the driving motors on the two sides so as to guide the absolute value of the angle difference value between the course angle of the robot and the target navigation angle to be within the preset angle error range; the absolute value of the angle difference between the course angle of the robot and the target navigation angle and the absolute value of the difference between the real-time rotating speeds of the driving motors correspondingly connected with the driving wheels arranged on the two sides of the robot form a positive correlation; the course angle of the robot is measured in real time by a built-in gyroscope of the robot; the driving wheels arranged on the two sides of the robot are respectively connected with a driving motor; the target navigation angle is pre-planned by the robot so as to guide the robot to walk along the pre-planned working path.

Specifically, the robot can adjust a PWM value used for controlling a driving motor through an angle closed-loop feedback adjusting device, the first PWM value adjusted in real time is input into the driving motor, the driving motor can change the output rotating speed, and then the course angle of the robot formed by the changed rotating speed correspondingly serves as the feedback input of the angle closed-loop feedback adjusting device to maintain closed-loop adjustment and indirectly perform closed-loop adjustment on the course angle measured by the robot in real time, wherein the closed-loop adjustment has a corresponding adjusting period. Accordingly, the method of closed-loop regulating a PWM value for controlling a drive motor includes: when the absolute value of the angle difference between the course angle measured in real time by the robot and the target navigation angle in the current regulation period is not within the preset angle error range, the absolute value of the angle difference between the course angle measured in real time and the target navigation angle in the current regulation period by the robot or the absolute value of the angle difference between the course angle measured in real time by the robot is configured as the feedback input of the next regulation period of the angle closed-loop feedback regulation device so as to carry out PID regulation on the PWM value for controlling the driving motor, wherein the closed-loop regulation is set as PID regulation in the embodiment; setting a real-time feedback regulation result of the PWM value for controlling the driving motor as the first PWM value, and regulating a first PWM value in each regulation period and obtaining the first PWM value in real time from the outside; inputting the first PWM value into a driving motor to adjust the course angle of the robot in real time until the absolute value of the angle difference value between the course angle measured by the robot in real time and the target navigation angle changes within a preset angle error range or keeps a constant value within the preset angle error range, keeping inputting the newly obtained first PWM value into the driving motor, performing PID (proportion integration differentiation) adjustment on the first PWM value to advance the closed-loop adjustment of the course angle measured by the robot in real time to approach the target navigation angle, and guiding the robot to walk along the direction corresponding to the target navigation angle; when the target navigation angle is excessively large or the robot stops first and then restarts to walk, the step S1 and the step S2 need to be executed again, generally, in a scene of colliding with an obstacle, the step S1 and the step S2 need to be executed again to recalculate the current relative walking resistance current value; the angle of the course angle of the robot is measured by a built-in gyroscope of the robot in real time.

The angle closed-loop feedback adjusting device can be divided into a first angle closed-loop feedback adjusting device and a second angle closed-loop feedback adjusting device, the first angle closed-loop feedback adjusting device is used for carrying out PID adjustment on the PWM value of the left driving motor, and the second angle closed-loop feedback adjusting device is used for carrying out PID adjustment on the PWM value of the right driving motor. The first angle closed-loop feedback adjusting device and the second angle closed-loop feedback adjusting device can be formed by PID controllers.

The method for closed-loop regulating the PWM value for controlling the driving motor comprises the following steps: under the condition that the absolute value of the angle difference value between the course angle measured by the robot in real time and the target navigation angle in the current regulation period is not within the preset angle error range, the robot controls the first angle closed-loop feedback regulation device to perform PID regulation on the PWM value for controlling the left driving motor; in the process of carrying out PID adjustment on a PWM value for controlling a left driving motor, a first angle closed-loop feedback adjusting device outputs the latest PWM value for controlling the left driving motor in the current adjusting period, a robot configures the difference value between the PWM value for controlling the left driving motor and a preset left target PWM value in the current adjusting period as the feedback input of the next adjusting period of the first angle closed-loop feedback adjusting device so as to reduce the difference value between the PWM value for controlling the left driving motor and the preset left target PWM value, the difference value becomes smaller along with the increase of time until the difference value is equal to zero, the first angle closed-loop feedback adjusting device can enter a stable state, and the course angle measured in real time by the robot is closer to a target navigation angle. The first angle closed-loop feedback adjusting device is a closed-loop control system with a negative feedback adjusting function. The robot sets the latest regulated and output PWM value for controlling the left driving motor as the first PWM value, then inputs the first PWM value into the left driving motor in real time to obtain the real-time rotating speed of the left driving motor, and the current signal output by the left driving motor can be sampled to feed back the resistance condition born by the left driving wheel on the walking surface; wherein, the real-time rotating speed of the left driving motor is in direct proportion to the first PWM value on the premise of not considering external resistance (such as friction and collision factors).

Meanwhile, under the condition that the absolute value of the angle difference value between the course angle measured by the robot in real time and the target navigation angle in the current adjusting period is not within the preset angle error range, the robot controls a second angle closed-loop feedback adjusting device to perform PID adjustment on the PWM value for controlling the right driving motor; in the process of carrying out PID adjustment on the PWM value for controlling the left driving motor, the second angle closed-loop feedback adjusting device outputs the latest PWM value for controlling the right driving motor in the current adjusting period, the robot configures the difference value between the PWM value for controlling the right driving motor and the preset right target PWM value in the current adjusting period as the feedback input of the next adjusting period so as to reduce the difference value between the PWM value for controlling the right driving motor and the preset right target PWM value, the difference value becomes smaller along with the increase of time until the difference value is zero, the second angle closed-loop feedback adjusting device can enter a stable state, and the course angle measured in real time by the robot is closer to the target navigation angle. The second angle closed-loop feedback adjusting device is a closed-loop control system with a negative feedback adjusting function. The robot sets the newly regulated PWM value for controlling the right driving motor as the first second PWM value, and then inputs the first second PWM value into the right driving motor to obtain the real-time rotating speed of the right driving motor, and the current signal output by the right driving motor can be sampled to feed back the resistance condition born by the right driving wheel on the walking surface; wherein, the real-time rotating speed of the right driving motor is in direct proportion to the first PWM value without considering the external resistance (such as friction and collision factors).

When the difference value between the PWM value for controlling the left driving motor and the preset left target PWM value is smaller than the first preset driving wheel steady-state error, and the difference value between the PWM value for controlling the right driving motor and the preset right target PWM value is smaller than the second preset driving wheel steady-state error, the robot adjusts the walking direction based on the difference value between the real-time rotating speed of the left driving motor and the real-time rotating speed of the right driving motor, the adjusting angle is determined by the difference value between the real-time rotating speed of the left driving wheel and the real-time rotating speed of the right driving wheel, and after the direction is adjusted, the real-time measured heading angle of the robot is configured as the feedback input of an angle closed-loop feedback adjusting device (comprising a first angle closed-loop feedback adjusting device and a second angle closed-loop feedback adjusting device) in the next adjusting period, so that the absolute value of the angle difference value between the heading angle of the robot and the target navigation angle is adjusted to be changed in the preset angle error range or kept at a constant value in the preset angle error range in the PID adjusting process. It should be noted that, in this embodiment, first, the robot measures the current heading angle in real time through the gyroscope, the real-time rotation speed of the left driving wheel is in direct proportion to the PWM value for controlling the left driving motor and has a preset conversion relationship, the real-time rotation speed of the right driving wheel is in direct proportion to the PWM value for controlling the right driving motor and has a preset conversion relationship, the radius of the left driving wheel is equal to the radius of the right driving wheel and symmetrically arranged on the left and right sides of the robot, and the circumference of the left driving wheel is equal to the circumference of the right driving wheel; the robot multiplies the difference value of the real-time rotating speed of the left driving wheel and the real-time rotating speed of the right driving wheel by the perimeter of the left driving wheel (or the perimeter of the right driving wheel), the multiplication result is marked as the difference value of the walking speed of the left driving wheel and the walking speed of the right driving wheel, the ratio of the multiplication result to the width of the robot body is set as the angular speed reached by the robot in the walking direction adjustment, the product of the angular speed reached by the robot in the walking direction adjustment and the walking direction adjustment time is set as the angle rotated by the robot in the walking direction adjustment, namely the adjustment angle, and the radian unit formed by calculation can be converted into an angle unit if necessary; the adjustment angle is gradually close to or even equal to the absolute value of the angle difference between the current course angle of the robot and the target navigation angle under the adjustment action of the angle closed-loop feedback adjustment device, wherein the preset angle error range comprises a numerical value 0, and the dimension is the same as the dimension applicable to the angle measured by the gyroscope. Preferably, when the chassis shape of the robot is a disc shape, the body width of the robot is the body diameter of the robot.

In the aforementioned embodiment of the closed-loop adjustment of the angle, the first PWM value comprises a first primary PWM value and a first secondary PWM value; a left driving wheel is arranged on the left side of the robot and is electrically connected with a left driving motor; the right side of robot installs right drive wheel, right drive wheel and right driving motor electric connection. In the process of closed-loop adjustment, the absolute value of the difference between the real-time rotating speed of the left driving motor and the real-time rotating speed of the right driving motor can form positive correlation with the absolute value of the angle difference between the course angle of the robot and the target navigation angle, namely, the absolute value of the angle difference between the course angle of the robot and the target navigation angle is larger, the absolute value of the difference between the real-time rotating speed of the left driving motor and the real-time rotating speed of the right driving motor is larger, the rotating speed difference between the left driving wheel and the right driving wheel is larger, but the deviation direction of the turning direction of the robot formed by the rotation of the left driving wheel and the right driving wheel and the walking direction of the robot relative to the direction indicated by the target navigation angle is opposite, so as to reduce the absolute value of the angle difference between the course angle of the robot and the target navigation angle and form negative feedback adjustment of the angle.

It should be noted that PID (Proportional Integral Derivative) regulation is a basic regulation method of a control system in the classical control theory, and is a linear regulation law with Proportional, integral and Derivative actions. The method is widely applied to industrial process control, and is particularly suitable for a deterministic control system capable of establishing an accurate mathematical model. When the structure and parameters of the controlled object cannot be completely mastered or an accurate mathematical model is not obtained, and other technologies of the control theory are difficult to adopt, the structure and parameters of the system controller must be determined by experience and field debugging, and the PID regulation technology is most conveniently applied. I.e., PID control techniques are best suited when a system and the controlled object are not completely known or system parameters cannot be obtained by effective measurement means. PID regulation, and in practice PI and PD control are also available. The PID control is controlled by calculating a control quantity by using proportion, integral and differential according to the error of the system. Increasing the proportionality coefficient Kp can reduce the static error of the system, but when Kp is too large, the dynamic quality of the system is deteriorated, the controlled quantity is oscillated, and even the closed-loop system is unstable. If the integral coefficient Ti is large, the integral effect is weak, otherwise, the integral effect is strong, the increase of Ti slows down the process of eliminating the static error, but can reduce the overshoot and improve the stability. When the differential coefficient Td is increased, the differential action is strengthened, which is helpful to reduce overshoot, overcome oscillation, stabilize the system, accelerate the response speed of the system, reduce the adjustment time, and improve the dynamic performance of the system.

Based on the embodiment, the application also discloses a mobile robot, wherein the left side and the right side of the mobile robot are respectively provided with a driving wheel, and a driving motor electrically connected with the driving wheels is arranged in the mobile robot; the mobile robot is also provided with a fan for adsorbing the mobile robot on a working surface; the coded disc can not be installed in the driving wheel, or the coded disc can be installed in the driving wheel; the mobile robot is configured to execute the method for detecting the walking distance of the robot to obtain the walking distance correction value of the robot.

The mobile robot is an intelligent window cleaning machine, and the intelligent window cleaning machine can further complete distance correction by combining the gravity influence and the difference caused by positive and negative rotation of the driving wheel on the basis of detecting the distance of the robot relative to the starting point position entering the walking state by adopting the method for detecting the walking distance by the intelligent robot, so that the cleaning quality, the walking efficiency and the cleaning coverage rate of the intelligent window cleaning machine are improved. When the mobile robot is a sucker type window cleaning machine, the driving wheels arranged on the left side and the right side are cleaning turnplates and are used for supporting the sucker type window cleaning machine to move on the work surface adsorbed by the sucker type window cleaning machine. Each cleaning turntable is correspondingly connected with a driving motor and receives the first PWM value control obtained in real time in the step S1 of the previous embodiment.

The intelligent window cleaning machine is a round intelligent window cleaning machine, and the left driving wheel and the right driving wheel are a left cleaning turntable and a right cleaning turntable. The intelligent window cleaning machine is a square intelligent window cleaning machine, and the left driving wheel and the right driving wheel are a left crawler wheel and a right crawler wheel. The intelligent window cleaning machine mainly comprises a round intelligent window cleaning machine and a square intelligent window cleaning machine, wherein the two intelligent window cleaning machines are firstly attached to glass when starting to work, a fan is turned on, and the two intelligent window cleaning machines are adsorbed on the glass through the suction force of the fan. And then the intelligent window cleaning machine sets the PWM value of the fan so as to control the robot to move.

In some embodiments, as can be seen from fig. 2, the intelligent window cleaning machine 1 is a suction cup type window cleaning machine, which moves and cleans by rotating two left and right cleaning rotating discs on the glass. The intelligent window cleaning machine 1 is characterized in that a left cleaning rotary disc 2 is set to be in a locking immobility mode, after a first PWM value is fixed by a right cleaning rotary disc 3, the right cleaning rotary disc is tightly attached to glass to rotate clockwise for a fixed time, then stops rotating and rotates anticlockwise for a fixed time, and when the right cleaning rotary disc 3 rotates clockwise or anticlockwise, the left cleaning rotary disc 2 is used as a motion center and rotates around the left cleaning rotary disc 2. The intelligent window cleaning machine 1 right cleaning turntable 3 is set to be in a locking motionless mode, after a first PWM value is fixed by the left cleaning turntable 2, the left cleaning turntable 2 is tightly attached to glass to rotate clockwise for a fixed time, then stops rotating and rotates anticlockwise for a fixed time, and when the left cleaning turntable 2 rotates clockwise or anticlockwise, the right cleaning turntable 3 is used as a motion center and rotates around the right cleaning turntable 3. And each cleaning turntable of the intelligent window cleaning machine needs to be subjected to action calibration, and then the method for detecting the walking distance by the robot is started, or the intelligent window cleaning machine enters the walking state from a static state and determines the blocking effect of overcoming the static friction force.

The logic and/or steps represented in the flowcharts or otherwise described herein, e.g., an ordered listing of executable instructions that can be considered to implement logical functions, can be embodied in any computer-readable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, processor-containing system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions. For the purposes of this description, a "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of the computer-readable medium would include the following: an electrical connection (electronic device) having one or more wires, a portable computer diskette (magnetic device), a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Further, the computer-readable medium could even be paper or another suitable medium upon which the program is printed, as the program can be electronically captured, via for instance optical scanning of the paper or other medium, then compiled, interpreted or otherwise processed in a suitable manner if necessary, and then stored in a computer memory.

The above embodiments are merely illustrative of the technical ideas and features of the present invention, and are intended to enable those skilled in the art to understand the contents of the present invention and implement the present invention, and not to limit the scope of the present invention. All equivalent changes or modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.

Claims

1. The robot detection walking distance method includes that driving wheels are installed on two sides of the robot, and a driving motor electrically connected with the driving wheels is installed inside the robot; the robot is also provided with a fan for adsorbing the robot on a working surface; the method for detecting the walking distance by the robot is characterized by comprising the following steps:

after the robot enters a walking state from a static state, the robot starts to walk on a working surface and acquires a first PWM value, and then integration processing is carried out on the acquired first PWM value within a specific PWM value range to determine a reference walking distance value of the robot; or in the process that the robot walks on the working surface, the robot sets the travel distance value measured in real time by the code disc installed on the robot as the reference travel distance value of the robot;

applying a matched distance conversion coefficient for the reference walking distance value of the robot by combining the relation between the walking direction of the robot and the gravity direction, and calculating a walking distance correction value of the robot;

the robot keeps performing closed-loop adjustment on a PWM value used for controlling the driving motor, and obtains a first PWM value in the closed-loop adjustment process.

2. The method for detecting the walking distance by the robot as claimed in claim 1, wherein before the robot starts to walk, the first PWM value is loaded to the driving motor to control the driving wheel to rotate so as to overcome the static friction force of the working surface until the first PWM value is greater than the preset starting threshold value, the robot is determined to enter the walking state from the static state so that the walking speed of the robot is in a linear relation with the first PWM value obtained in real time, and then the robot starts to walk on the working surface so as to overcome the blocking effect of the static friction force from the working surface;

the preset starting threshold value is a PWM value determined by setting that driving wheels of the robot enter the walking state on working surfaces with different friction forces; the arrangement mode of the working face comprises vertical arrangement, horizontal arrangement or inclined arrangement.

3. The method for detecting the walking distance by the robot according to claim 2, wherein the method for integrating the acquired first PWM value within the specific PWM value range comprises:

after the robot enters a walking state, the robot samples a first PWM value within preset sampling time, integrates all the first PWM values which are sampled within the preset sampling time and are larger than a preset starting threshold value, and sets an integration result of the first PWM values as a reference walking distance value of the robot; the specific PWM value range refers to a PWM value range which is larger than a preset starting threshold value;

and within the preset sampling time, the walking speed of the robot is in direct proportion to the first PWM value sampled by the robot.

4. The method for detecting the walking distance by the robot as claimed in claim 3, wherein in the preset sampling time, a timer arranged in the robot triggers an interrupt signal every other unit sampling time, and the robot samples the first PWM value every time the interrupt signal is detected; and the first PWM value is used for feeding back the walking speed of the robot in each unit sampling time.

5. The method for detecting the walking distance by the robot according to claim 1, wherein the method for calculating the walking distance correction value of the robot by applying the corresponding distance conversion coefficient to the reference walking distance value of the robot in combination with the relationship between the walking direction of the robot and the gravity direction comprises:

the robot measures the walking direction of the robot on a working surface in real time through a gyroscope, and determines the pose relation between the walking direction of the robot and the gravity direction;

when the walking direction of the robot is not vertical to the gravity direction, if the walking direction of the robot is arranged upwards relative to the horizontal plane, the robot is determined to walk upwards on the working surface relative to the horizontal plane, and the walking distance correction value of the robot is determined by controlling the currently calculated reference walking distance value to be multiplied by a first distance conversion coefficient;

when the walking direction of the robot is not vertical to the gravity direction, if the walking direction of the robot is arranged downwards relative to the horizontal plane, the robot is determined to walk downwards on the working surface relative to the horizontal plane, and the currently calculated reference walking distance value is controlled to be multiplied by a second distance conversion coefficient, so that the walking distance correction value of the robot is determined;

wherein the working surface is not arranged parallel to the horizontal plane; the direction of gravity is vertically downward.

6. The method for detecting the walking distance by the robot as claimed in claim 5, wherein when the robot walks on the working surface upward relative to the horizontal plane, the walking direction of the robot is set to a first preset inclined direction; when the robot walks downwards on the working surface relative to the horizontal surface, the walking direction of the robot is set to be a second preset inclined direction; the first preset inclination direction and the second preset inclination direction are symmetrical; on the same working surface, the first distance conversion coefficient and the second distance conversion coefficient are reciprocal;

the time spent by the robot walking in the first preset inclination direction through the first preset reference distance value is marked as upward test time, and the time spent by the robot walking in the second preset inclination direction through the first preset reference distance value is marked as downward test time;

on the premise that the ratio of the downward test time to the upward test time is set as a first distance conversion coefficient by the robot, when the robot walks on the working surface along a first preset inclined direction, the calculated walking distance correction value of the robot is smaller than a reference walking distance value;

on the premise that the ratio of the downward test time to the upward test time is set as a second distance conversion coefficient by the robot, when the robot walks in a second preset inclined direction on the working surface, the calculated walking distance correction value of the robot is smaller than the reference walking distance value;

on the premise that the ratio of the upward test time to the downward test time is set as a first distance conversion coefficient by the robot, when the robot walks on the working surface along a first preset inclined direction, the calculated walking distance correction value of the robot is greater than a reference walking distance value;

and on the premise that the ratio of the upward test time to the downward test time is set as a second distance conversion coefficient by the robot, when the robot walks in a second preset inclined direction on the working surface, the calculated walking distance correction value of the robot is greater than the reference walking distance value.

7. The method for detecting the walking distance by the robot as claimed in claim 6, wherein a first preset reference distance value is used for representing the distance between the boundary of the uppermost end of the working surface and the boundary of the lowermost end of the working surface;

the robot linearly walks to the boundary of the uppermost end of the working surface from the boundary of the lowermost end of the working surface along a first preset inclined direction, and the consumed time is upward test time;

and the robot linearly travels to the boundary of the lowest end of the working surface from the boundary of the uppermost end of the working surface along a second preset inclined direction, and the consumed time is downward test time.

8. The method for detecting the walking distance of the robot according to claim 5, wherein the method for calculating the walking distance correction value of the robot by applying the corresponding distance conversion coefficient to the reference walking distance value of the robot in combination with the relationship between the walking direction of the robot and the gravity direction further comprises:

when the walking direction of the robot is vertical to the gravity direction, if the walking direction of the robot is a first preset horizontal direction vertical to the gravity direction, controlling the currently calculated reference walking distance value to be multiplied by a third distance conversion coefficient, and determining a walking distance correction value of the robot;

when the walking direction of the robot is vertical to the gravity direction, if the walking direction of the robot is a second preset horizontal direction vertical to the gravity direction, controlling the currently calculated reference walking distance value to be multiplied by a fourth distance conversion coefficient, and determining a walking distance correction value of the robot;

the first preset horizontal direction points to one side of the working surface, and the second preset horizontal direction points to the other side of the working surface.

9. The method for detecting a walking distance by a robot according to claim 8, wherein the time taken for the robot to walk in the first preset horizontal direction for the second preset reference distance is marked as a first test time, and the time taken for the robot to walk in the second preset horizontal direction for the second preset reference distance is marked as a second test time;

the robot sets the ratio of the first test time to the second test time as a third distance conversion coefficient; or the robot sets the ratio of the second test time to the first test time as a third distance conversion coefficient;

the first preset horizontal direction and the second preset horizontal direction are symmetrical; and on the same working surface, the third distance conversion coefficient and the fourth distance conversion coefficient are reciprocal.

10. The method for detecting a walking distance by a robot according to claim 9, wherein the second preset reference distance value is a distance between a boundary of a leftmost end of the working surface and a boundary of a rightmost end of the working surface;

the robot linearly walks to the boundary of the rightmost end of the working surface from the boundary of the leftmost end of the working surface along a first preset horizontal direction, and the consumed time is first test time;

and the robot linearly walks to the boundary of the leftmost end of the working face from the boundary of the rightmost end of the working face along a second preset inclination direction, and the consumed time is second test time.

11. The method for detecting the walking distance by the robot as claimed in claim 5, wherein if the working surface is parallel to the gravity direction, the robot is configured to be adsorbed on the working surface, and the robot walks on the working surface to allow the driving wheels of the robot to rotate forwards or backwards on the working surface;

if the working surface is perpendicular to the gravity direction, the robot is not configured to be adsorbed on the working surface, and the driving wheels of the robot are allowed to rotate forwards or backwards on the working surface when the robot walks on the working surface.

12. The method for detecting the walking distance of the robot as claimed in claim 1, wherein the method for performing closed-loop adjustment on the PWM value for controlling the driving motor comprises:

under the condition that the absolute value of the angle difference value between the course angle measured by the robot in real time and the target navigation angle in the current regulation period is not within the preset angle error range, carrying out PID regulation on the PWM value for controlling the driving motor by the robot, in the process of carrying out PID regulation on the PWM value for controlling the driving motor, taking the difference value between the PWM value for controlling the driving motor and the first preset target PWM value in the current regulation period as the feedback input of the next regulation period, so as to reduce the difference value between the PWM value for controlling the driving motor and the first preset target PWM value, setting the PWM value for controlling the driving motor as the first PWM value, and inputting the first PWM value into the driving motor on the corresponding side in real time to obtain the driving wheel current sampling value output by the driving motor on the side, wherein after the robot enters the walking state, the real-time rotating speed of the driving motor is in direct proportion to the first PWM value;

for the driving motors correspondingly connected with the driving wheels arranged on each side of the robot, when the PWM value used for controlling the driving motors on the corresponding sides and the first preset target PWM value are smaller than the steady-state error of the corresponding preset driving wheels, the robot adjusts the walking direction based on the difference value of the real-time rotating speeds of the driving motors on the two sides so as to guide the absolute value of the angle difference value between the course angle of the robot and the target navigation angle to be within the preset angle error range; the absolute value of the angle difference between the course angle of the robot and the target navigation angle and the absolute value of the difference between the real-time rotating speeds of the driving motors correspondingly connected with the driving wheels arranged on the two sides of the robot form a positive correlation;

the course angle of the robot is measured in real time by a built-in gyroscope of the robot; the driving wheels arranged on the two sides of the robot are respectively connected with a driving motor; the target navigation angle is pre-planned by the robot to guide the robot to walk along the pre-planned working path.

13. A mobile robot is characterized in that the left side and the right side of the mobile robot are respectively provided with a driving wheel, and a driving motor electrically connected with the driving wheels is arranged in the mobile robot; the mobile robot is also provided with a fan which is used for adsorbing the mobile robot on a working surface; characterized in that the mobile robot is configured to perform the method of detecting a walking distance of the robot of any one of claims 1 to 12.

14. The mobile robot of claim 13, wherein when the mobile robot is a suction cup type window cleaner, the left and right driving wheels are cleaning turntable for supporting the suction cup type window cleaner to move on the work surface to which the suction cup type window cleaner is attached.