CN110575371A

CN110575371A - intelligent blind-guiding walking stick and control method

Info

Publication number: CN110575371A
Application number: CN201911005985.6A
Authority: CN
Inventors: 杜海英; 张峰瑀; 张杨润; 张笑川; 吴宇辉; 孙舒鹏
Original assignee: Dalian Nationalities University
Current assignee: Dalian Minzu University
Priority date: 2019-10-22
Filing date: 2019-10-22
Publication date: 2019-12-17
Anticipated expiration: 2039-10-22
Also published as: CN110575371B

Abstract

an intelligent blind-guiding walking stick and a control method thereof belong to the technical field of intelligent walking sticks. The technical scheme is as follows: the handle passes through the stick support and is connected with the connecting box, and the connecting box is connected with the return pulley, and control system set up in one or more of handle, stick support, connecting box, main control unit is connected with GPS positioning system, infrared system of seeking marks, fall down detecting system, supersound obstacle-sheltering system, voice broadcast system, electrical power generating system, wireless transmission system respectively. The intelligent blind-guiding walking stick has the beneficial effects that the intelligent blind-guiding walking stick is a multifunctional driving type intelligent blind-guiding walking stick which integrates the functions of GPS positioning, wireless help calling, infrared tracking, ultrasonic obstacle avoidance and the like; the intelligent blind-person walking aid has the advantages that starting from the formulation of a trip plan by the blind person, navigation and positioning in the whole process, infrared tracing of blind tracks in the process, medium-distance and long-distance ultrasonic obstacle avoidance, a function of intimate voice music broadcasting in the process, loss prevention, falling prevention prompt, an intelligent help calling device, a self-charging system and the like are achieved.

Description

intelligent blind-guiding walking stick and control method

Technical Field

the invention belongs to the technical field of intelligent walking sticks, and particularly relates to an intelligent blind-guide walking stick and a control method.

Background

The current development situation at home and abroad is as follows:

1.1 State of the Art in the domestic and foreign sciences

Development of infrared detection technology

yuanhua et al, 2008, conducted analytical studies on infrared detection. It has excellent environmental adaptability and the advantages of small volume and light weight, and plays an excellent role in the aspects of environmental problems, transportation problems, meeting problems, conflict problems, armed conflict problem supervision, military equipment control and the like. For the development of infrared detection in information acquisition technology, developed countries such as the united states actively explore spectral bands. And made great progress.

(II) development of ultrasonic obstacle avoidance technology

Borenstein J et al, 2008, developed a mobile robotic system capable of performing various tasks for disabled persons. To avoid collision of an accidental obstacle, the mobile robot uses an ultrasonic range finder for detection and mapping. The obstacle avoidance strategy of the robot depends on the performance of the ultrasonic range finder to a great extent.

(III) development of Wireless Transmission technology

The break-and-break in 2011 analyzed the development of wireless transmission technology. As a result, as human science has progressed, the application of wireless transmission technology has become more widespread, and it is generally composed of a wireless base station, a wireless terminal, and a corridor management server. Today, wireless transmission technology is mainly used in mobile communication, bluetooth technology, and wireless broadband.

(IV) development of GPS technology

in 2012, the united states successfully launched a third GPS IIF satellite, which is an advance in its satellite constellation modernization program. Development and production of a new generation of GPS IIIA navigation satellites and modernization of the ground segment are also underway along with the GPS IIF satellite transmissions. With the improvement of the navigation precision and the expansion of the application range of the GPS, the GPS is still a 'Lao Ge' in the global satellite navigation field.

Development of Mecanum wheel

Based on the omnidirectional movement performance of the Mecanum wheels, the body can move in any direction, so that the method has a considerable application prospect in the fields of manufacturing and warehouse logistics automation. In 2013, Chen Bo et al put forward a feasible wheel design method and manufacturing process, and an omnibearing mobile platform based on Mecanum wheels provides theoretical basis for a control algorithm by using kinematics and a theoretical model, so that independent design and development are performed.

1.2 State of the Art Intelligent Walking stick at home and abroad

Romteera Khlaikhayai et al put forward a new concept in 2011, namely a walking stick which is composed of wireless sensors and can be used for safe navigation for the old and the blind. The wireless sensors include an ad hoc network that can be implemented within the hand wand to provide group communication between them and to provide navigation information and networks. The system has the advantages of providing safety protection for the old and the blind, and implementing and realizing special activities such as blind meeting, disabled person network and the like.

the utility model discloses a develop a section based on ultrasonic ranging technique and digital display function in 2015 year zhongpeng et al, still the voice prompt function closes as an organic whole, and a multi-functional intelligent stick of making can show the user that the distance between current stick and the place ahead barrier gives the stick in real time. The cane consists of three main modules: the ultrasonic wave module, control processing module and information output module. The distance measurement of the walking stick only needs to be within three hundred millimeters, and the error is about two millimeters.

Kher Chaitrali et al in 2016 proposed a navigation device for visually impaired people, which mainly applied infrared sensing technology, radio frequency identification technology and Android equipment to provide voice output for obstacle prevention and navigation. The navigation device is provided with a near-distance infrared sensor, RFID tags are installed in public buildings and on walking sticks of the blind, and an application program is designed for family members and can access the position of the blind through a server when needed.

the research and development of a multifunctional intelligent walking stick approved in 2017 and the like, wherein the walking stick comprises a handle part and a main body part, a button is arranged on the handle, and a searchlight controlled by the button is embedded in the front end of the handle; the near infrared blood sugar detection device is arranged in the upper end area in front of the handle, a hole for detecting blood pressure is formed in the middle of the handle, and a battery box for supplying power to an electric device is arranged in the handle; the handle is internally provided with a GPS signal receiver and a microprocessor. The front searchlight is arranged, so that the illumination function can be provided; the rod body is designed to be a telescopic rod, and the length of the rod body can be adjusted; the medicine box is attached, so that the convenience and the beauty are realized; the handle can detect the position of the blind at any time through the built connection in the satellite positioning.

at present, the research on intelligent walking sticks at home and abroad is deep, and a plurality of walking sticks with various functions are also available, wherein the mature walking stick is a brand-new multifunctional intelligent walking stick of Fuji general company, and the main function of the Fuji general intelligent walking stick is that if the distance from the blind to an obstacle is less than 130 cm, the voice broadcasting function of the walking stick can automatically broadcast the obstacle distance to remind the blind to pay attention to safety. The current direction, the real-time and the short message can be broadcasted for help through the keys. The computer system is connected, so that the current geographic position of the intelligent walking stick can be detected and checked, the living characteristics of the relevant user are given, and family and health data of the user can be provided. If any problems are found, the smart cane will automatically turn on emergency services and location navigation. The handle is provided with a GPS positioning module, a 3G communication module and a wireless network module. These functions are intended to solve the problem of getting lost by the elderly or visually impaired.

The proportion of people aged 65 years and above by Japanese is as high as twenty-seven percent, and is the country with the most aging population in the world at present. China is 11%, the ranking is the tenth, and science and technology products for the elderly population are also important for the domestic market. Therefore, the intelligent walking stick aims to maintain the basic functions of the intelligent walking stick while being innovative, is low in design and use cost, easy to popularize and high in commercial value and social value.

disclosure of Invention

In order to provide all-directional intelligent service for the trip of the blind, the invention provides the intelligent blind guiding walking stick and the control method.

the technical scheme is as follows:

an intelligent blind-guiding cane comprising: handle, stick support, connecting box, return pulley, control system, the handle pass through the stick support with the connecting box is connected, the connecting box with the return pulley is connected, control system set up in one or more in handle, stick support, the connecting box, control system includes: the intelligent anti-falling system comprises a main controller, a GPS (global positioning system), an infrared tracing system, a falling detection system, an ultrasonic obstacle-shielding system, a voice broadcasting system, a power supply system and a wireless transmission system, wherein the main controller is respectively connected with the GPS, the infrared tracing system, the falling detection system, the ultrasonic obstacle-shielding system, the voice broadcasting system, the power supply system and the wireless transmission system.

the intelligent control system further comprises a two-dimensional code recognition system, a fault detection system and an environment mode switching system, wherein the two-dimensional code recognition system, the fault detection system and the environment mode switching system are all connected with the main controller.

Further, the ultrasonic shielding system comprises two SSD-ME007TX ultrasonic ranging modules, and each SSD-ME007TX ultrasonic ranging module comprises: the ultrasonic transmitter, the receiver and the controller are connected with each other; the infrared tracing system comprises a plurality of infrared sensors and an image recognition sensor, the infrared sensors are installed on the bottom wheels, and the image recognition sensor is installed at the joint of the handle and the walking stick bracket; the tumble detection system comprises a gyroscope and a pressure sensor, and the gyroscope and the pressure sensor are arranged in the walking stick bracket; the voice broadcasting system is arranged at the joint of the handle and the walking stick bracket; the main controller is an STM32f103zet6 controller; the power supply system is an LM2596 power supply module.

Furthermore, the bottom wheel is sunken downwards by one side of the connecting box, and protrudes upwards by one side far away from the connecting box.

further, the infrared sensing illuminating lamp is further included and installed on the connecting box.

The invention also comprises a control method of the intelligent blind guiding walking stick, which comprises the following steps:

the ultrasonic obstacle avoidance system detects obstacles within 2-3.5 m around the walking stick, carries out voice prompt on the obstacles entering the range, carries out synchronous positioning by the GPS positioning system in the process of advancing, transmits signals to the GPS positioning system after detecting that the obstacles exist in front, plans a reasonable route by the GPS positioning system according to the positioning condition and time, converts the geographical position and route information into voice signals and transmits the voice signals to the voice module for voice broadcasting prompt, and guides the blind person to advance;

The infrared tracing system detects the blind track reflected light, the main controller receives different reflected light detection signals, and the forward direction of the trolley is controlled by processing the reflected light detection signals;

Whether the gyroscope detects that the walking stick inclines, the pressure sensor detects the instantaneous impact force size of walking stick when receiving pressure, and the inclination angle and the tilting rate that combine the gyroscope judge the walking stick is placed or is fallen down on the ground, if detect to fall down, send signal for wireless transmission module, send place geographical position information with the SMS form to in advance set up outside receiving equipment on, in time carry out automatic SOS.

Further, the ultrasonic obstacle avoidance system measures distance once every 50ms, and outputs a distance value in a serial port mode after the distance measurement is completed; when no obstacle in front is detected, the vehicle continues to move straight; when an obstacle in front is detected, the steering engine stops moving and the direction is switched; detecting after the direction is converted, and continuing to move straight when no obstacle is detected in front; when an obstacle is detected in front, the direction is switched.

Further, in the above-mentioned case,

When encountering blind road turning: when a left turn occurs, the left side of the motor arranged in the blind guiding walking stick vibrates strongly, so that the left turn is prompted; when a right turn occurs, the right side of the motor arranged in the blind guiding walking stick vibrates strongly, so that the right turn is prompted;

when the width and the depth of the blind road are increased, fine adjustment is carried out for many times by adjusting the differential speed of two wheels;

When meeting an intersection, the infrared sensor starts the zebra crossing recognition function, and when the red sensor detects white zebra crossing stripes on the ground, the blind person is guided to go ahead from the zebra crossing;

When the traffic light is encountered, an image recognition sensor is adopted, an image shot by a sensor head passes through a lens and is converted into an electric signal through a light receiving element, and the brightness and the shape of a target object are distinguished according to light and shade information distributed in the number of pixels of the light receiving element; when the advancing direction is detected to be a red light, voice broadcasting is timely carried out to prompt the blind to stop advancing in situ for waiting, and when a green light is detected, the blind is prompted to continue advancing; storing digital information of seconds of traffic lights by defining a cyclic detection mode, processing image information by a camera, and judging whether the traffic lights can safely pass through the intersection in the remaining time if the traffic lights are green lights by matching an infrared sensor and an ultrasonic module; if the red light is detected, specific waiting time is reported through voice; the camera analyzes moving vehicles and pedestrians in advance, and reports road condition information in time through voice broadcast.

further, the infrared tracing step is as follows:

s1, initializing a task counter, and setting an initial value X;

S2, when the white line deviates by delta X to the right, adjusting the direction to the right, decelerating the right wheel and accelerating the left wheel;

When the white line deviates delta X to the left, the direction is adjusted to the left, the left wheel decelerates, and the right wheel accelerates;

s3, judging whether the white line is in the middle, if so, executing; if not, return is made to step S2.

Further, the fall detection steps are as follows:

T1, electrifying and vibrating a gyroscope;

t2, detecting whether the capacitance of the gyroscope changes;

t3, when the capacitance of the gyroscope changes, calculating the change value of the angular velocity;

T4, judging whether the angular speed variation value exceeds 0.5 pi rad/s;

T5, if the variation value of the angular speed does not exceed 0.5 pi rad/s, the mobile communication module is triggered to alarm.

the invention has the beneficial effects that:

The intelligent blind-guiding walking stick is a multifunctional driving type intelligent blind-guiding walking stick integrating functions of GPS positioning, wireless distress calling, infrared tracking, ultrasonic obstacle avoidance and the like. The intelligent blind-person walking aid has the advantages that starting from the formulation of a trip plan by the blind person, navigation and positioning in the whole process, infrared tracing of blind tracks in the process, medium-distance and long-distance ultrasonic obstacle avoidance, a function of intimate voice music broadcasting in the process, loss prevention, falling prevention prompt, an intelligent help calling device, a self-charging system and the like are achieved. Provides a comprehensive solution for the inconvenient trip problem of the blind. A sentence, a stick is in hand, the whole course is carefree. The blind person can conveniently go out, and the safety, intelligence and high-quality guarantee are provided.

drawings

FIG. 1 is a diagram of a background art Fushitong intelligent cane;

FIG. 2 is a hardware functional block diagram of the intelligent blind guiding walking stick of the invention;

FIG. 3 is a hardware circuit diagram of the SSD-ME007TX ultrasonic ranging module of the present invention;

FIG. 4 is a flow chart of ultrasonic obstacle avoidance according to the present invention;

FIG. 5 is a circuit diagram of the GPS navigation system hardware of the present invention;

FIG. 6 is an overall structure diagram of the intelligent blind guiding walking stick of the invention;

Figure 7 is a schematic view of the wheel turning angle of the present invention;

FIG. 8 is a flowchart of the infrared tracking of the present invention;

FIG. 9 is a circuit diagram of the infrared tracking hardware of the present invention;

FIG. 10 is a hardware circuit diagram of a fall detection system of the present invention;

FIG. 11 is a flow chart of the fall detection system of the present invention;

FIG. 12 is a bottom wheel structure of the intelligent blind guiding cane of the present invention;

FIG. 13 is a power module hardware circuit diagram of the present invention;

FIG. 14 is a schematic diagram of the power input/output port of the present invention;

FIG. 15 is a circuit diagram of the MCU master control interface and each module interface according to the present invention;

the reference numerals in fig. 6 are as follows: the intelligent walking stick comprises a handle 1, a walking stick support 2, a connecting box 3, a bottom wheel 4, a voice broadcasting system 5, an image recognition sensor 6, a gyroscope 7, an infrared sensor 8 and an infrared sensing illuminating lamp 9.

Detailed Description

The intelligent blind guiding walking stick and the control method are further explained with reference to the attached fig. 1-15.

an intelligent blind-guiding cane comprising: handle 1, stick support 2, connecting box 3, return pulley 4, control system, handle 1 through stick support 2 with connecting box 3 is connected, connecting box 3 with return pulley 4 is connected, control system set up in one or more in handle 1, stick support 2, connecting box 3, control system includes: the intelligent anti-falling system comprises a main controller, a GPS (global positioning system), an infrared tracing system, a falling detection system, an ultrasonic obstacle-shielding system, a voice broadcasting system, a power supply system and a wireless transmission system, wherein the main controller is respectively connected with the GPS, the infrared tracing system, the falling detection system, the ultrasonic obstacle-shielding system, the voice broadcasting system, the power supply system and the wireless transmission system.

further, the ultrasonic shielding system comprises two HC-SR04 ultrasonic ranging modules, and each HC-SR04 ultrasonic ranging module comprises: the ultrasonic wave transmitter, the receiver and the controller are connected with each other.

Furthermore, the bottom wheel 4 is recessed downward near one side of the connection box 3 and protrudes upward far away from one side of the connection box 3.

Further, the infrared tracking system comprises a plurality of infrared sensors 8 and an image recognition sensor 6, wherein the infrared sensors 8 are installed on the bottom wheels 4, and the image recognition sensor 6 is installed at the joint of the handle 1 and the walking stick support 2.

Further, the fall detection system comprises a gyroscope 7 and a pressure sensor, wherein the gyroscope 7 and the pressure sensor are arranged in the walking stick support 2.

Further, the voice broadcasting system 5 is arranged at the joint of the handle 1 and the walking stick support 2.

further, the main controller is an STM32f103zet6 controller.

Further, the power supply system is an LM2596 power supply module.

first, introduction of function

The intelligent blind guiding walking stick provides all-round intelligent service for the traveling of the blind, and the intelligent blind guiding walking stick is a multifunctional driving type intelligent blind guiding walking stick which integrates the functions of GPS positioning, wireless help calling, infrared tracking, ultrasonic obstacle avoidance and the like. The intelligent blind-person walking aid has the advantages that starting from the formulation of a trip plan by the blind person, navigation and positioning in the whole process, infrared tracing of blind tracks in the process, medium-distance and long-distance ultrasonic obstacle avoidance, a function of intimate voice music broadcasting in the process, loss prevention, falling prevention prompt, an intelligent help calling device, a self-charging system and the like are achieved. Provides a comprehensive solution for the inconvenient trip problem of the blind. A sentence, a stick is in hand, the whole course is carefree. The blind person can conveniently go out, and the safety, intelligence and high-quality guarantee are provided.

secondly, the intelligent blind guiding walking stick comprises the following functions

this intelligence is led blind stick and is used STM32f103zet6 as main control unit, and the ultrasonic wave of collection keeps away the barrier, and infrared trail system, GPS navigation positioning system, environmental mode switched systems, voice broadcast system, fall down detecting system, wireless transmission system and failure diagnosis system power module system etc. the intelligence of system leads blind stick hardware functional block diagram and is shown in fig. 2.

1. obstacle avoidance function:

The blind guiding walking stick adopts an ultrasonic sensor array to detect obstacles within 2-400 cm around the walking stick and carries out voice prompt on the obstacles entering the range. The ultrasonic ranging module is selected from HC-SR04, can provide 2CM-400CM non-contact distance sensing function, has ranging precision up to 3mm, and comprises an ultrasonic transmitter, a receiver and a control circuit. The working principle of the module is as follows: and the power supply and the ground are connected to the ultrasonic module. Inputting a high-level square wave with the length of 20us to a pulse trigger pin (trig); after the wave is input, the module can automatically emit 8 sound waves of 40KHz, and simultaneously the level of an echo pin (echo) end is changed from 0 to 1; (at which time a timer should be started). When the ultrasonic wave returns to be received by the module, the level of the echo pin end is changed from 1 to 0; (the timer should be stopped counting at this time), and the time counted by the timer is the total time of the ultrasonic wave from the emission to the return. The measured distance can be calculated based on the velocity of the sound in air being 344 m/s.

And after the distance measurement is finished, outputting the distance value in a serial port mode. The height and the angle of the ultrasonic obstacle avoidance module are set, so that the blind can effectively avoid obstacles such as vehicles and street lamps in front in the advancing process, meanwhile, the obstacle avoidance system is connected with the GPS navigation system, synchronous positioning is carried out in the advancing process, signals are timely transmitted to the GPS system after the ultrasonic probe finds that the obstacles exist in front, the GPS plans a reasonable route according to the positioning condition and time, and then converts the geographical position and route information into voice signals to be transmitted to the voice module for voice broadcasting and prompting, so that the blind is guided to advance. The hardware circuit diagram of the ultrasonic obstacle avoidance system is shown in fig. 4. The main program of the ultrasonic obstacle avoidance system is as follows:

2. Navigation and positioning

the navigation and POSITIONING SYSTEM of the intelligent blind guiding walking stick adopts a GLOBAL POSITIONING SYSTEM (GPS) navigation.

navigation function and path planning:

a voice assistant is installed at the walking stick terminal, voice input can be carried out on the target position, the target position is determined, a GPS navigation system is used for line optimization and selection, and meanwhile voice broadcasting prompt is carried out in a timely mode.

in the aspect of intelligent crutch route planning, a Dijkstra algorithm is adopted to search the shortest route, and the Dijkstra algorithm, namely a greedy algorithm, can be used for searching the shortest route between two specified points or the shortest route from one specified point to all other points. According to the initial point of the intelligent crutch, the point closest to the initial point is found and added into a set in sequence, and d [ i ] of all the points in the set is the shortest path length from the point to the initial point.

Setting two vertex sets T and S, wherein the S stores the vertexes with the shortest paths found, initially, only one vertex in the set S, namely a source point V0, stores the vertexes which do not find the shortest paths currently, and then selects a shortest path (V0..... Vk) with the shortest current length from the set T, so that the Vk is added into the vertex set S, and the shortest path length from a far point V0 to each vertex in the T is modified; this step was repeated until all points were added with S. In the program, dist [ n ] indicates the length of the shortest path from the source point V0 to the destination point Vi that is currently found, and when initialized, dist [ i ] is edge [ V0] [ i ], S [ n ] is 0, which indicates that the vertex Vi is not added to the set S, S [ V0] is 1 when initialized, and the rest is 0, and path [ n ] is path [ i ] which indicates the vertex number before the vertex Vi on the shortest path from V0 to Vi. Using the "reverse tracing" method, each vertex on the shortest path from V0 to Vi is determined. The main procedure is as follows:

this allows the previous point and path of each way to be found by the edge, where node u can be stored directly if it is stored with an adjacency matrix

the positioning function is as follows:

After the walking stick is powered on, the system positions the walking stick in real time, meanwhile, walking stick position information sharing service is provided, the walking stick position can be shared by relatives and police officers, and humanized anti-loss and anti-lost functions are provided. The circuit diagram of the GPS hardware is shown in fig. 5.

3. infrared tracking system

The system is based on infrared sensor tracking, and the working principle of the system is that the yellow color of a blind road and the dark color of a pedestrian road form a large color difference, the sensor receives different reflected light detection signals due to the difference of the reflection intensity of the dark color and the light color to infrared light, and the controller of the blind guiding walking stick obtains different level signals, so that the control of the advancing direction of the trolley is realized.

When the walking stick works, the wheels at the lower end of the intelligent blind guiding walking stick are designed into a groove structure with the depth of 5mm, so that a blind road and the wheels form a good embedded structure and stably run. The whole structure of the blind guiding walking stick is shown in figure 6.

special case processing:

When encountering blind road turning:

When a left turn occurs, the motor arranged in the left side of the blind guiding walking stick vibrates strongly, so that the left turn is prompted.

when the blind road parameters slightly change:

when the parameters slightly change, such as the width of a blind road increases and the depth increases, and the position is adjusted, fine adjustment is carried out for multiple times by adjusting the differential speed of two wheels.

When a zebra crossing is encountered:

When meeting an intersection or a crossroad, the infrared sensor starts the zebra crossing recognition function, and when the red sensor detects white zebra crossing stripes on the ground, the blind person is guided to go ahead from the zebra crossing stripes.

OpenMV two-dimensional code recognition

The two-dimensional code recognition adopts an OpenMV4 module, and a camera of OpenMV4 is a circuit board which is small, low in power consumption and low in cost, and helps people easily complete machine vision (machine vision) application. By a high level language Python script (just micro Python), rather than C/C + +. The high-level data structure of Python makes it easy for you to process complex outputs in machine vision algorithms, can easily use external terminals to trigger photography or to execute algorithms, and can also use the results of the algorithms to control IO pins. The method for reading the QR code in the visual field of the crutch by adopting the OpenMV Cam is characterized in that the label in the environment can be read by QR code detection/decoding, the read two-dimensional code information is transmitted to a Main Control Unit (MCU) STM32 chip in a serial port mode, different instructions are sent according to different received information, and different functions of the crutch are realized. The main procedure is as follows:

And (3) traffic light identification:

with the image recognition sensor, an image captured by a sensor head (camera) is converted into an electric signal by a light receiving element (CMOS imaging sensor) after passing through a lens. Then, the brightness and shape of the object are determined based on the light/shade and shade information assigned to the number of pixels of the light receiving element. The light receiving element is of a color type. Since the received light information is analyzed into three primary colors (RGB) and the respective gray levels are recognized, unlike the monochrome type in which the gray levels of two black and white poles are used for recognition, it is possible to discriminate even a color having a small difference in shade.

When meeting the intersection with the traffic light, the walking stick can respectively detect the red light and the green light in two directions and distinguish the detected colors. And judging a result and giving a corresponding instruction to the processor, if the advancing direction is detected to be a red light, timely carrying out voice broadcasting to prompt the blind person to stop advancing in situ for waiting, and prompting the blind person to continue advancing when a green light is detected. The digital information of the second number of the traffic lights is stored by defining a circulating detection mode, image information processing is carried out through a camera, and at the moment, an infrared sensor and an ultrasonic module are matched, and if the traffic lights are green lights, whether the traffic lights can safely pass through the intersection in the remaining time is judged. If be the red light, then have specific latency through voice broadcast. In addition, the camera analyzes moving vehicles and pedestrians in advance, and reports road condition information in time through voice broadcast.

the infrared tracking flow chart is shown in fig. 8, and the hardware circuit diagram is shown in fig. 9.

4. Tumble detection system

The falling detection system reads a three-axis angular velocity value and a three-axis acceleration value transmitted back by the MPU6050 through the installed gyroscope 7 (model MPU6050), carries out algorithm analysis on the acceleration and the angular velocity of the collected Z axis, and judges that the blind person holding the walking stick falls down when the acceleration value and the angular velocity of the Z axis are suddenly increased to a set preset value. The acceleration full-scale range is set to be +/-4 g, when the acceleration value of the Z axis reaches +/-2 g, the deflection angle is calculated to reach +/-45 degrees through the angular velocity, whether the acceleration value and the deflection angle value exceed the values or not is inquired through voice broadcasting, and whether the acceleration value and the deflection angle value fall or not is immediately judged.

If the falling-down blind person is determined, an alarm is sent out in time, the mobile communication module is triggered, the geographical position information is sent to preset external receiving equipment in a short message mode, and automatic help seeking is carried out in time, so that the falling-down blind person can be helped at the first time. The circuit of the fall detection system is shown in fig. 9, and the block diagram of the process is shown in fig. 10.

The main procedures of the fall detection gyroscope and accelerometer are as follows:

5. voice broadcast

The voice broadcasting system needs to cover all functional systems in the connected walking stick, carries out voice broadcasting on road conditions in the advancing process, guides the direction of an advancing route when a front obstacle is detected, monitors the electric quantity of the walking stick in real time and carries out voice alarm when the electric quantity is exhausted. Meanwhile, the voice system is provided with the Bluetooth module, and the Bluetooth module can be connected with the earphone, so that the blind can conveniently receive information in time.

6. Exercise system

According to the analysis of the following characteristics of the blind road, the blind guide strips on the blind road are 5mm higher than the ground, and the default blind road strips are parallel to each other and have equal intervals. The wheel structure shown in fig. 12 is designed, similar to the wheels of a train, the blind walking stick can stably run on the blind track strips similar to a railway track, the wheels are in contact with the blind track strips through an inclined surface, the influence of most of sand and stones on the walking of the blind guiding walking stick is reduced, and the tracking precision is improved.

The turning is realized by adopting a two-wheel differential motion mode, when the blind guiding walking stick moves forwards, the two wheels rotate anticlockwise, and when the blind guiding walking stick moves backwards, the two wheels rotate clockwise.

Solutions to the sports system in summary: two motors adopt Hall direct current coding motors, the speed is measured by an M method through a coder mode of a main control STM32 timer, the numerical value of a motor coder is read once every 10ms, namely, the high level time is detected, the speed of each wheel can be calculated, the obtained coder numerical value is calculated each time, the obtained speed is used as an actual value Encoder of incremental PID regulation, and then the actual value Target wanted by the user is subjected to difference to obtain deviationThe difference can be calculated to obtain the current variation Bias and the accumulated deviation Integral_biasAnd Last deviation Last_biasand then through an incremental PID control formula:

PWM_Δ＝K_p*Bias+K_i*Intergral_bias+K_d＊(Bias-Last_bias) (1)

and obtaining the target speed PWM of the motor, and then assigning corresponding PWM to the motor through the STM32, so that the two motors are ensured to keep the same speed in the process of straight running. When the deviation of turning or tracking is needed, the turning or adjustment can be realized by changing the speed of one motor through a two-wheel differential method, such as: when a left turn is needed, the Target value Target of the right wheel motor is increased, and the Target value of the left wheel motor is appropriately reduced, so that the purpose of turning or adjusting is achieved.

the differential speed control routine is as follows:

7. fault detection system

The method comprises the steps of diagnosing whether each sensor works normally or not by setting a diagnostic program, analyzing and detecting faults by combining knowledge reasoning of a trained neural network, broadcasting the faults by a voice assistant, and transmitting position information and fault information to an emergency contact person set in advance through a communication module.

8. Environmental mode switching system

When the blind person needs to go to public places such as supermarkets or hospitals, the artificial intelligence assistant can automatically identify the destination and switch the corresponding mode, when the blind person enters the supermarket mode, the infrared distance meters on the two sides of the blind guiding stick are slightly inclined towards the upper oblique direction so as to detect the goods shelves on the two sides and ensure that the blind person can safely walk in the channel of the goods shelves, meanwhile, the two-dimensional code identification module is started, the type of the goods is judged by analyzing the two-dimensional codes of the goods on the goods shelves, then image identification is carried out, and specific goods including prices and basic information of the goods are analyzed through an internal neural network in a mode of being connected with the Internet. After shopping is finished, the built-in display screen of the blind guiding walking stick automatically displays the payment code to finish payment.

9. Power module system

The power supply adopts the LM2596 power module, almost can reach 75% power efficiency in general actual operation, and the cost performance is higher. LM2596 is selected as the power module in this experiment. The input voltage is 7-12V, the output voltage is 5V, the output current is 1A, and an AC/DC power converter is arranged in the converter. Simultaneously, the power supply part of the system adopts the solar cell panel to carry out electric power complementation, the periphery of the solar cell panel is provided with photosensitive elements, and the solar cell panel rotates along with the rotation of the light intensity direction by judging the intensity of light, so that the illumination of the largest area is obtained. The hardware circuit diagram of the power module is shown in fig. 13. The power supply has two interfaces, one of which can input and output 3.3 or 5V voltage. A schematic diagram of the power input/output port is shown in fig. 14.

three-in-one hardware design

The MCU master interface and the interface circuits of the modules are shown in fig. 15.

Example 2

An intelligent blind guiding walking stick control method comprises the following steps:

further, in the above-mentioned case,

Further, the infrared tracing step is as follows:

s1, initializing a task counter, and setting an initial value X;

further, the fall detection steps are as follows:

t1, electrifying and vibrating a gyroscope;

T2, detecting whether the capacitance of the gyroscope changes;

T4, judging whether the angular speed variation value exceeds 0.5 pi rad/s;

the above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be able to cover the technical solutions and the inventive concepts of the present invention within the technical scope of the present invention.

Claims

1. An intelligent blind guiding cane, comprising: handle (1), stick support (2), connecting box (3), return pulley (4), control system, handle (1) through stick support (2) with connecting box (3) are connected, connecting box (3) with return pulley (4) are connected, control system set up in one or more in handle (1), stick support (2), connecting box (3), control system includes: the intelligent anti-falling system comprises a main controller, a GPS (global positioning system), an infrared tracing system, a falling detection system, an ultrasonic obstacle-shielding system, a voice broadcasting system, a power supply system and a wireless transmission system, wherein the main controller is respectively connected with the GPS, the infrared tracing system, the falling detection system, the ultrasonic obstacle-shielding system, the voice broadcasting system, the power supply system and the wireless transmission system.

2. The intelligent blind-guiding walking stick of claim 1, further comprising a two-dimensional code recognition system, a fault detection system and an environmental mode switching system, wherein the two-dimensional code recognition system, the fault detection system and the environmental mode switching system are all connected with the main controller.

3. The intelligent blind-guiding cane of claim 1, wherein the ultrasonic mask system comprises two SSD-ME007TX ultrasonic ranging modules, each SSD-ME007TX ultrasonic ranging module comprising: the ultrasonic transmitter, the receiver and the controller are connected with each other; the infrared tracing system comprises a plurality of infrared sensors (8) and an image recognition sensor (6), the infrared sensors (8) are installed on the bottom wheels (4), and the image recognition sensor (6) is installed at the joint of the handle (1) and the walking stick bracket (2); the tumble detection system comprises a gyroscope (7) and a pressure sensor, wherein the gyroscope (7) and the pressure sensor are arranged in the walking stick bracket (2); the voice broadcasting system (5) is arranged at the joint of the handle (1) and the walking stick bracket (2); the main controller is an STM32f103zet6 controller; the power supply system is an LM2596 power supply module.

4. the intelligent blind-guiding cane according to claim 1, characterized in that the bottom wheel (4) is recessed downwards near the side of the connection box (3) and protrudes upwards away from the side of the connection box (3).

5. The intelligent blind-guiding cane according to claim 1, characterized in that it further comprises an infrared-sensing illumination lamp (9), the infrared-sensing illumination lamp (9) being mounted on the connection box (3).

6. An intelligent blind guiding walking stick control method is characterized by comprising the following steps:

7. The intelligent blind-guiding walking stick control method as claimed in claim 6, wherein the ultrasonic obstacle avoidance system measures distance every 50ms, and outputs a distance value in a serial port form after the distance measurement is completed; when no obstacle in front is detected, the vehicle continues to move straight; when an obstacle in front is detected, the steering engine stops moving and the direction is switched; detecting after the direction is converted, and continuing to move straight when no obstacle is detected in front; when an obstacle is detected in front, the direction is switched.

8. the intelligent blind guiding cane control method as claimed in claim 6,

9. The intelligent blind-guiding cane control method as claimed in claim 6, characterized in that the infrared tracing step is as follows:

S1, initializing a task counter, and setting an initial value X;

10. The intelligent blind-guiding cane control method of claim 6, wherein the fall detection steps are as follows:

T1, electrifying and vibrating a gyroscope;

t2, detecting whether the capacitance of the gyroscope changes;

t4, judging whether the angular speed variation value exceeds 0.5 pi rad/s;