CN110605717A

CN110605717A - Mechanical arm, unmanned aerial vehicle automatic battery replacement system and mechanical arm control method

Info

Publication number: CN110605717A
Application number: CN201910883368.XA
Authority: CN
Inventors: 崔鹏
Original assignee: Beijing Sankuai Online Technology Co Ltd
Current assignee: Beijing Sankuai Online Technology Co Ltd
Priority date: 2019-09-18
Filing date: 2019-09-18
Publication date: 2019-12-24

Abstract

The invention discloses a mechanical arm, an automatic battery replacement system of an unmanned aerial vehicle and a control method of the mechanical arm. This robotic arm includes the manipulator, and the manipulator includes: the device comprises a base, a driving mechanism, a first finger, a second finger and a manipulator controller; the first finger and the second finger are arranged on the base in a reverse linkage manner; the tail ends of the first finger and the second finger, which contact the object, are provided with touch sensors for acquiring pressure values; the first finger and/or the second finger are/is connected with an angle sensor; and the manipulator controller controls the driving mechanism to drive the first finger and the second finger to open or close according to the difference between the pressure values of the touch sensors and the finger angle acquired by the angle sensor. The feedback that robotic arm snatched the object can be accurately obtained to usable touch sensor of this application to snatch the position according to feedback condition adjustment, thereby improve and snatch the action, this mode response speed is fast, does not have mechanical separation, and control is simple easy, and the cost is lower.

Description

Mechanical arm, unmanned aerial vehicle automatic battery replacement system and mechanical arm control method

Technical Field

The invention relates to the technical field of robot design, in particular to a mechanical arm, an automatic battery replacement system of an unmanned aerial vehicle and a mechanical arm control method.

Background

In the current increasingly automated production process, the application of the robot obviously improves the efficiency of assembly line work and saves a lot of manpower and material resources. However, in the existing robot design process, the grabbing feedback method of the robot arm still has defects, which affect the control accuracy of the robot arm.

For example, the joint current feedback method of the robot arm is only suitable for the direct drive condition or the condition with a small reduction ratio, because the joint friction force is small under the conditions, the loss is small, the feedback is accurate, and the robot arm control can be realized, but under the condition that the friction force causes large consumption, the friction force model required to be considered by the control model is extremely complex, so that a good control effect cannot be obtained, and the method is expensive, so the application is limited.

Disclosure of Invention

In view of the problems of complex model and poor control effect of a mechanical arm feedback mode in the prior art, the invention provides the mechanical arm, the unmanned aerial vehicle automatic battery replacement system and the mechanical arm control method, so as to overcome the problems.

In order to achieve the purpose, the invention adopts the following technical scheme:

according to an aspect of the present invention, there is provided a robot arm including a robot hand including: the device comprises a base, a driving mechanism, a first finger, a second finger and a manipulator controller;

the first finger and the second finger are arranged on the base in a reverse linkage manner; the tail ends of the first finger and the second finger, which contact the object, are provided with touch sensors for acquiring pressure values; the first finger and/or the second finger are/is connected with an angle sensor for obtaining a corresponding finger angle; and the manipulator controller controls the driving mechanism to drive the first finger and the second finger to move in an opening mode or in a closing mode according to the difference between the pressure values of the touch sensors of the first finger and the second finger and the finger angle acquired by the angle sensor.

Optionally, the first finger and the second finger are both link mechanisms and symmetrically arranged on the base;

the drive mechanism includes: the first gear is rigidly connected with the first finger, the second gear is rigidly connected with the second finger, the third gear is connected with the motor, the first gear is meshed with the second gear, and the third gear is meshed with the first gear.

Optionally, the angle sensor is a potentiometer, and the robot further includes: a fourth gear, the potentiometer being rigidly connected to the fourth gear, the fourth gear being in mesh with the second gear;

and the second gear wheel drives the fourth gear wheel to rotate when rotating, so that the potentiometer acquires the real-time angle of the finger.

Optionally, the first finger and the second finger are both parallelogram linkages.

Optionally, the touch sensor surfaces of the first finger and the second finger are attached with an elastic material with a preset thickness.

Optionally, the manipulator further comprises a travel switch for limiting the distance the manipulator moves relative to the object.

Optionally, the mechanical arm further comprises a mechanical arm and a mechanical arm controller, wherein the mechanical arm controller is used for controlling the mechanical arm to drive the mechanical arm to realize three-axis orthogonal motion.

Optionally, the mechanical arm includes a first sliding table, a second sliding table, and a third sliding table; the first sliding table is arranged along a vertical direction and is connected to the second sliding table in a sliding manner, the second sliding table is arranged along a horizontal first direction and is connected to the third sliding table and the fourth sliding table in a sliding manner, and the third sliding table is arranged along a horizontal second direction;

under the control of the mechanical arm controller, the first sliding table drives the mechanical arm to slide along the vertical direction, the second sliding table drives the first sliding table to slide along the horizontal first direction, and the third sliding table drives the second sliding table to slide along the horizontal second direction.

Optionally, the mechanical arm further comprises a fourth sliding table, and the fourth sliding table and the third sliding table are arranged in parallel and used for jointly supporting and driving the second sliding table to slide.

According to another aspect of the invention, an automatic battery replacement system for an unmanned aerial vehicle is provided, and the system comprises the unmanned aerial vehicle, a charging cabin, an aircraft guide table, a general control system and a mechanical arm as described in any one of the above; the total control system comprises a total controller, the total controller is connected with the mechanical arm controller and the mechanical arm controller of the mechanical arm, and the mechanical arm is controlled to grab the battery in the charging cabin to replace the battery for the unmanned aerial vehicle.

Optionally, the master control system further comprises an unmanned aerial vehicle control system, an aircraft guide platform controller and a charging cabin management system; the master controller is in wireless communication with the unmanned aerial vehicle control system, and is in bus communication with the aircraft guide platform controller, the mechanical arm controller and the charging cabin management system.

Optionally, the aircraft guide platform is capable of lifting and lowering movement in a vertical direction, and a guide post for guiding the landing of the drone is arranged on an upper surface of the aircraft guide platform.

According to still another aspect of the present invention, there is provided a robot control method applied to the robot described in any one of the above, the method including:

acquiring pressure values of touch sensors of the first finger and the second finger, and acquiring finger angles acquired by the angle sensors;

and adjusting the position of the manipulator to the side of the touch sensor with larger pressure value, and controlling the closing degree of the first finger and the second finger to enable the first finger and the second finger to simultaneously contact the grabbed object.

Optionally, the basis for determining that the first finger and the second finger simultaneously contact the grabbed object is as follows: the difference between the pressure values of the touch sensors of the first finger and the second finger is smaller than a preset value, and the minimum value of the pressure values is larger than zero.

Alternatively, when the control vector of the robot arm is represented by P, the control vector of the robot arm is represented by θ, the pressure value of the tactile sensor of the first finger is represented by P1, and the pressure value of the tactile sensor of the second finger is represented by P2, P ═ F_pid(P2-P1)，θ＝R_pid(P2-P1) wherein F_pidAnd R_pidThe method is a time domain form of a PID transfer function, and the method controls the mechanical arm and the mechanical arm to move according to control vectors p and theta respectively.

Optionally, the method further comprises:

and a preset distance is set for the travel switch, and the travel switch is controlled to be triggered after contacting the grabbed object and moving for the preset distance, so that the mechanical arm stays at a position suitable for grabbing the grabbed object.

Optionally, the adjusting the position of the manipulator comprises:

controlling the first sliding table to lift along the vertical direction, so that the manipulator moves to the level of the grabbed object;

controlling the second sliding table to drive the first sliding table to slide along the horizontal first direction, so that the manipulator moves to be horizontally aligned with the grabbed object;

and controlling the third sliding table to drive the second sliding table and the first sliding table to integrally slide along the horizontal second direction, so that the manipulator is close to the grabbed object along the horizontal alignment direction.

In conclusion, the beneficial effects of the invention are as follows:

the touch sensor is arranged at the tail end of the finger in reverse linkage to obtain the pressure value, the angle sensor connected with the finger is arranged to obtain the angle of the finger, and the data can be used for obtaining the feedback of the grabbing action of the manipulator, so that the deviation of the grabbing action is judged and adjusted to control the first finger and the second finger to grab the object more accurately. And because the pressure detection element touch sensor is arranged at the position where the tail end of the finger contacts the object and is at the same position as the finger of the implementation element, the response speed is high, the inertia influence of mechanical obstruction does not exist, and the manipulator is simpler to control and has lower cost.

Drawings

FIG. 1 is a schematic cross-sectional view of a robot in an embodiment of the robot of the present invention;

FIG. 2 is a schematic perspective view of the robot shown in FIG. 1;

FIG. 3 is a front view of the robot shown in FIG. 1;

FIG. 4 is a schematic view of the robot of FIGS. 1-3 grasping an object;

FIG. 5 is a schematic diagram illustrating an adjustment of the grabbing action shown in FIG. 4;

fig. 6 is a schematic diagram of an automatic power switching system for an unmanned aerial vehicle according to an embodiment of the present invention, which is installed with the robot arm shown in fig. 1 to 5;

fig. 7 is a side view of the automatic power swapping system of the unmanned aerial vehicle shown in fig. 6;

fig. 8 is a schematic diagram of a general control system of the automatic battery replacement system of the unmanned aerial vehicle shown in fig. 6;

fig. 9 is a schematic diagram illustrating a method for controlling a robot according to an embodiment of the present invention;

in the figure: 100. a manipulator; 101. a motor; 102. a base; 103. a first finger; 104. a second finger; 105. a first gear; 106. a second gear; 107. a third gear; 108. a fourth gear; 109. a potentiometer; 110. a travel switch; 111. a first tactile sensor; 112. a second tactile sensor; 200. a mechanical arm; 201. a first sliding table; 202. a second sliding table; 203. a third sliding table; 204. a fourth slide table; 300. an unmanned aerial vehicle; 400. a charging cabin; 500. an aircraft guide table; 600. an onboard battery; 601. and a clamping end.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present application, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.

The technical conception of the invention is as follows: the feedback mode of controlling the mechanical arm to grab the object is improved, the tactile sensor is arranged at the tail end of the finger in reverse linkage to acquire the pressure value, the angle sensor connected with the finger is arranged to acquire the angle of the finger, the feedback of grabbing actions of the mechanical arm is obtained by utilizing the data, and therefore the deviation of the grabbing actions is judged and adjusted to control the first finger and the second finger to grab the object more accurately. And because the pressure detection element touch sensor is arranged at the position where the tail end of the finger contacts the object and is at the same position as the finger of the implementation element, the response speed is high, the inertia influence of mechanical obstruction does not exist, and the manipulator is simpler and quicker to control and has lower cost.

Fig. 1 to 3 show the structural composition of the robot arm according to an embodiment of the present invention, and fig. 4 to 5 show the adjustment process of the robot arm for gripping an object according to the embodiment.

As shown in fig. 1 to 3, a robot arm includes a robot arm 100, and the robot arm 100 includes: a base 102, a drive mechanism, a first finger 103, a second finger 104, and a robot controller.

A first finger 103 and a second finger 104 are arranged on the base 102 in a reverse linkage manner; the ends of the first finger 103 and the second finger 104 contacting the object are provided with tactile sensors for acquiring pressure values. As shown in fig. 1 to 3, a first tactile sensor 111 is disposed inside the end of the first finger 103, and a second tactile sensor 112 is disposed inside the end of the second finger 104.

In addition, an angle sensor is connected to the first finger 103 and/or the second finger 104 for obtaining a corresponding finger angle. In this embodiment, the angle sensor is a potentiometer 109, indicating a change in finger angle by a change in voltage.

The robot controller can determine the gripping action deviation of the first finger 103 and the second finger 104 according to the pressure value difference of the touch sensors of the first finger 103 and the second finger 104 and the finger angle obtained by the angle sensor, and then control the driving mechanism to drive the first finger 103 and the second finger 104 to open or close, so as to quickly and accurately grip the object.

As shown in fig. 4, the object to be grasped is an on-board battery 600. Initially, the centerline of the robot 100 is positioned above the centerline of the gripping end 601 of the on-board battery 600. When the manipulator 100 of the embodiment starts to grab, the lower second tactile sensor 112 will collect pressure data before the first tactile sensor 111, that is, the pressure value P2 of the second tactile sensor 112 is greater than the pressure value P1 of the first tactile sensor 111. Therefore, by comparing the pressure difference between the two touch sensors, the deviation condition of the grabbing position can be judged, and the grabbing action of the manipulator 100 can be adjusted accordingly, in the process, the basis for controlling the opening and closing degree of the fingers is the finger angle acquired by the angle sensor in real time.

As shown in FIG. 5, the motion adjustment is a process that gradually converges when the first touch sensor 111 and the second touch sensor 112 acquire the pressure difference y_diffAnd finally, when the center line of the manipulator 100 is smaller than the preset value (approaches to zero), the center line of the manipulator coincides with the center line of the clamping end 601 at the moment, so that adaptive adjustment of the grabbing position is realized, and stable grabbing can be realized. Moreover, since the tactile sensor for detecting the pressure is provided at the end of the finger contacting the grasped object, the position for feedback detection and the position for application of force are the same, and the feedback is rapid and accurateAnd the cost is lower.

In the present embodiment, the first finger 103 and the second finger 104 are both link mechanisms, and are symmetrically disposed on the base 102. The drive mechanism includes: a motor 101, a first gear 105, a second gear 106 and a third gear 107, wherein the first gear 105 is rigidly connected to the first finger 103, the second gear 106 is rigidly connected to the second finger 104, the third gear 107 is connected to the motor 101, the first gear 105 and the second gear 106 are engaged, and the third gear 107 is engaged with the first gear 105. When the motor 101 drives the third gear 107 to rotate, the third gear 107 drives the first gear 105 and the second gear 106 to rotate simultaneously through gear transmission, so as to control the first finger 103 and the second finger 104 to be linked reversely.

For example, in the present embodiment, when the motor 101 rotates clockwise, the first finger 103 and the second finger 104 are driven to perform a closing motion, and when the motor 101 rotates counterclockwise, the first finger 103 and the second finger 104 are driven to perform an opening motion.

In this embodiment, the angle sensor is a potentiometer 109, and the robot arm 100 further includes: a fourth gear 108, a potentiometer 109 is rigidly connected to the fourth gear 108, and the fourth gear 108 is engaged with the second gear 106.

When the second gear 106 rotates, the fourth gear 108 is driven to rotate, so that the potentiometer 106 outputs potential change, and the real-time angle of the finger is acquired. The robot controller can easily adjust the robot 100 to grasp objects of different sizes depending on the real-time position of the finger.

In this embodiment, as shown in fig. 1, the first finger 103 and the second finger 104 are both parallelogram link mechanisms, and can move symmetrically in opposite directions along with the rotation of the gear, and of course, finger structures in other link forms can also be applied to this application, and are not described herein again.

In this embodiment, the elastic material with a preset thickness is attached to the surfaces of the tactile sensors of the first finger 103 and the second finger 104, and the elastic material is used to increase the bandwidth of the feedback data of the tactile sensors, so that the pressure value changes of the first tactile sensor 111 and the second tactile sensor 112 can be ensured to be continuous and gentle, and the pressure value data of the two can be compared more conveniently and accurately to perform the adjustment of the grabbing action.

In the present embodiment, the robot arm 100 further includes a travel switch 110, and the travel switch 110 is used to limit the distance that the robot arm 100 moves relative to the object to be grasped. As shown in fig. 1 and 4, the stroke switch 110 is provided between the two fingers so as to control the robot arm 100 to stay at a position suitable for grasping by limiting the distance at which the robot arm 100 approaches the grasped object by contacting the grasped object.

In the present embodiment, the robot arm further includes a robot arm 200 (see fig. 6) and a robot arm controller, under the control of the robot arm controller, the robot arm 200 can drive the robot arm 100 to perform three-axis orthogonal motions to adjust the positions where the first finger 103 and the second finger 104 of the robot arm 100 grasp the object.

As shown in fig. 6, the robot arm 200 includes a first slide table 201, a second slide table 202, and a third slide table 203. Use vertical direction to be Z, the horizontal orthogonal direction is X and Y, establishes rectangular coordinate system, and first slip table 201 sets up along vertical Z direction, and sliding connection is on second slip table 202, and second slip table 202 sets up along horizontal first direction X, and sliding connection is on third slip table 203, and third slip table 203 sets up along horizontal second direction Y. The third sliding table 203 is fixed on the bottom surface to fix the whole robot arm.

Under the control of manipulator controller, first slip table 201 can drive manipulator 100 and slide along vertical direction, and second slip table 202 can drive first slip table 201 and slide along horizontal first direction X, and third slip table 203 can drive second slip table 202 and slide along horizontal second direction Y, finally realizes manipulator 100's triaxial orthogonal motion, changes the position in order to snatch airborne battery 600 in a flexible way.

In this embodiment, referring to fig. 6, the robot arm 200 further includes a fourth sliding table 204, and the fourth sliding table 204 and the third sliding table 203 are arranged in parallel and are used for jointly supporting the robot arm and driving the second sliding table 202 to slide.

In the present embodiment, as shown in the front view of fig. 3, two first tactile sensors 111 and two second tactile sensors 112 are provided, and are respectively disposed at the left and right ends of the corresponding finger, so that the left and right pressure values of the tactile sensors on the left and right sides of the same finger can be compared to determine whether the manipulator 100 is displaced left or right with respect to the object. Of course, the tactile sensor can be arranged in more ways according to the shape and size of the object to be grabbed, and the tactile sensor is not described herein again.

The application also discloses automatic system of trading of unmanned aerial vehicle, refer to the embodiment shown in fig. 6 to 8, this automatic system of trading of unmanned aerial vehicle includes: unmanned aerial vehicle 300, charging cabin 400, aircraft guide table 500, robotic arm and the overall control system as any one above. The total control system comprises a total controller, the total controller is connected with a mechanical arm manipulator controller and a mechanical arm controller of a mechanical arm, the mechanical arm is controlled to grab a battery in the charging cabin 400 and change the battery of the unmanned aerial vehicle 300, the battery of the unmanned aerial vehicle 300 is automatically changed, manpower is saved, and the speed is faster.

As shown in fig. 8, the general control system further includes an unmanned aerial vehicle control system, an aircraft guide stage controller, and a charging cabin management system. The main controller is in wireless communication with the unmanned aerial vehicle control system to remotely cooperate with the unmanned aerial vehicle to take off and land, and the main controller is in bus communication with the aircraft guide table controller, the mechanical arm controller and the charging cabin management system.

In this embodiment, the aircraft guide table 500 is capable of elevating movement in the vertical direction under the control of the aircraft guide table controller, and the upper surface of the aircraft guide table 500 is arranged with guide pillars for guiding the landing of the drone 300 to more accurately control the landing position of the drone 300.

In practical application, the master controller can be used as a control center to centralize computing resources and realize computing and overall management. The mechanical arm sends a pressure value obtained by the touch sensor and finger angle data obtained by the potentiometer to the master controller, the master controller coordinates the mechanical arm controller and the mechanical arm controller through calculation, a displacement instruction is sent to the mechanical arm controller to enable each sliding table to move, the position of the whole mechanical arm relative to the airborne battery is adjusted, and meanwhile, the master controller sends a closing instruction to the mechanical arm controller to continue to control finger closing. Assuming that the control vector of the robot arm is p and the control vector of the robot arm 100 is θ, it can be seen that both p and θ can be set to be pressed with respect to the second tactile sensor 112The final result of the control of the force value P2 and the pressure value P1 of the first tactile sensor 111 is that the centerline of the robot 100 converges with the centerline of the gripper end 601, i.e., y_diffAt this time, the two fingers can clamp the clamping end 601 to realize stable grabbing.

The application also discloses a robot control method, which is applied to any one of the above robot control methods, and as shown in fig. 9, the method includes:

step S910; the method comprises the steps of obtaining pressure values of the touch sensors of the first finger and the second finger, and obtaining finger angles collected by the angle sensors.

Step S920: the position of the manipulator is adjusted to one side of the touch sensor with a large pressure value, and the closing degree of the first finger and the second finger is controlled, so that the first finger and the second finger can simultaneously contact the grabbed object, the self-adaptive action adjustment of the manipulator is realized, and the grabbing action is accurate and stable.

In this embodiment, the basis for determining that the first finger and the second finger simultaneously contact the object to be grasped is as follows: the difference between the pressure values of the tactile sensors of the first finger and the second finger is smaller than a preset value, the preset value approaches zero, and the minimum value of the pressure values is larger than zero.

In this embodiment, when P represents a control vector of the robot arm, θ represents a control vector of the robot arm, P1 represents a pressure value of the tactile sensor of the first finger, and P2 represents a pressure value of the tactile sensor of the second finger, P ═ F_pid(P2-P1)，θ＝R_pid(P2-P1) wherein F_pidAnd R_pidThe method is a time domain form of a PID transfer function, and the method is based on a proportional-derivative-integral principle and controls the motion of the mechanical arm and the mechanical arm according to control vectors p and theta respectively.

In this embodiment, the method further includes: and a preset distance is set for the travel switch, so that the travel switch is triggered after contacting the grabbed object and moving for the preset distance, and the mechanical arm is controlled to stop at a position suitable for grabbing.

In this embodiment, adjusting the position of the manipulator specifically includes:

the first sliding table is controlled to lift along the vertical direction, so that the manipulator moves to the level of being grabbed.

The second sliding table is controlled to drive the first sliding table to slide along the horizontal first direction, so that the manipulator moves to be horizontally aligned with the grabbed object.

The three processes can be used in a crossed manner, and after the initial movement of each sliding table, further fine adjustment movement is possibly needed, so that the manipulator is accurately aligned with the object to be grabbed and is close to the object to be grabbed finally.

To sum up, the robotic arm of this application, through set up touch sensor in terminal contact object position department of finger, acquire the pressure value to can judge the deviation condition of snatching the action through tactile feedback, then combine the finger angle, realize that self-adaptation snatchs the action adjustment, need not to adopt advanced sensor (like visual sensor etc.) location, control method is simple, and the cost is lower, and, because the position that the feedback detected is the same with the position of snatching, therefore response speed is fast, mechanical structure's isolation and inertial interference have been avoided, control is quick effective.

While the foregoing is directed to embodiments of the present invention, other modifications and variations of the present invention may be devised by those skilled in the art in light of the above teachings. It should be understood by those skilled in the art that the foregoing detailed description is for the purpose of better explaining the present invention, and the scope of the present invention should be determined by the scope of the appended claims.

Claims

1. A robot arm comprising a robot arm, characterized in that the robot arm comprises: the device comprises a base, a driving mechanism, a first finger, a second finger and a manipulator controller;

2. The robotic arm of claim 1, wherein the first finger and the second finger are each a linkage mechanism symmetrically disposed on the base;

3. The robot arm of claim 2, wherein the angle sensor is a potentiometer, the robot arm further comprising: a fourth gear, the potentiometer being rigidly connected to the fourth gear, the fourth gear being in mesh with the second gear;

4. A robot arm as claimed in claim 2, wherein the first and second fingers are each a parallelogram linkage.

5. The robotic arm of claim 1, wherein the tactile sensor surfaces of the first and second fingers are attached with a predetermined thickness of an elastic material.

6. The robot arm of claim 1, further comprising a travel switch for limiting the distance the robot arm moves relative to the object being grasped.

7. The mechanical arm according to claim 1, further comprising a mechanical arm and a mechanical arm controller, wherein the mechanical arm controller is configured to control the mechanical arm to drive the mechanical arm to realize three-axis orthogonal motion.

8. The mechanical arm according to claim 7, wherein the mechanical arm comprises a first sliding table, a second sliding table and a third sliding table; the first sliding table is arranged along a vertical direction and is connected to the second sliding table in a sliding manner, the second sliding table is arranged along a horizontal first direction and is connected to the third sliding table and the fourth sliding table in a sliding manner, and the third sliding table is arranged along a horizontal second direction;

9. The mechanical arm according to claim 8, wherein the mechanical arm further comprises a fourth sliding table, and the fourth sliding table and the third sliding table are arranged in parallel and used for jointly supporting and driving the second sliding table to slide.

10. An automatic battery replacement system for an unmanned aerial vehicle, which is characterized by comprising the unmanned aerial vehicle, a charging cabin, an aircraft guide table, a general control system and a mechanical arm according to any one of claims 1 to 9; the total control system comprises a total controller, the total controller is connected with the mechanical arm controller and the mechanical arm controller of the mechanical arm, and the mechanical arm is controlled to grab the battery in the charging cabin to replace the battery for the unmanned aerial vehicle.

11. The unmanned aerial vehicle automatic battery replacement system according to claim 10, wherein the general control system further comprises an unmanned aerial vehicle control system, an aircraft guide table controller and a charging cabin management system; the master controller is in wireless communication with the unmanned aerial vehicle control system, and is in bus communication with the aircraft guide platform controller, the mechanical arm controller and the charging cabin management system.

12. The unmanned aerial vehicle automatic power switching system of claim 11, wherein the aircraft guide table is capable of lifting and lowering movement in a vertical direction, and a guide pillar for guiding the unmanned aerial vehicle to land is arranged on an upper surface of the aircraft guide table.

13. A robot control method applied to a robot according to any one of claims 1 to 9, comprising:

14. The robot arm control method according to claim 13, wherein the determination that the first finger and the second finger simultaneously contact the object to be grasped is based on: the difference between the pressure values of the touch sensors of the first finger and the second finger is smaller than a preset value, and the minimum value of the pressure values is larger than zero.

15. The robot arm control method according to claim 13, wherein the control vector of the robot arm is represented by P, the control vector of the robot arm is represented by θ, the pressure value of the tactile sensor of the first finger is represented by P1, the pressure value of the tactile sensor of the second finger is represented by P2, and then P is F_pid(P2-P1)，θ＝R_pid(P2-P1) wherein F_pidAnd R_pidThe method is a time domain form of a PID transfer function, and the method controls the mechanical arm and the mechanical arm to move according to control vectors p and theta respectively.

16. The robot arm control method of claim 13, further comprising:

17. The robot arm control method of claim 13, wherein the adjusting the position of the robot arm comprises: