A dexterous hand control system and control method for multi-dimensional force tactile adaptive grasping

Abstract

The present invention relates to the field of manipulator control technology, and in particular to a dexterous hand control system and control method for multi-dimensional force tactile adaptive grasping, wherein the control system includes a host computer, a dexterous hand master controller module, and a finger controller module, a three-dimensional force tactile sensor module, and an actuator module independently configured for each finger of the dexterous hand; wherein the dexterous hand master controller receives host computer instructions and generates control instructions corresponding to each finger; the three-dimensional force tactile sensor monitors the contact data between the finger and the object; the finger controller calculates the target position of the servo motor at different time points based on the control instruction, contact data, and actuator state feedback, and generates a third control instruction; after receiving the instruction, the actuator module adjusts the servo motor position to ensure that the dexterous hand completes adaptive grasping according to a predetermined trajectory and strength. The present invention can adaptively adjust the grasping strength and speed of the dexterous hand according to different situations to ensure the accuracy and stability of the grasping action.

Description

Technical Field

[0001] The present invention relates to the technical field of manipulator control, and in particular to a dexterous hand control system and a control method for multi-dimensional force tactile adaptive grasping. Background Art

[0002] With the rapid development of robotics, robots have been widely used in manufacturing, medical, service and other fields. Among them, dexterous hands, as robot hands that simulate the functions of human fingers, have become a hot topic in robotics research. Control algorithms are the key to determining the flexibility and accuracy of dexterous hands. Although traditional PID control and impedance control are widely used in the field of robot control, they have limitations when handling complex tasks.

[0003] At present, the control system of dexterous hands mostly adopts open-loop control based on position sensors, which only controls the actuator according to the preset position instructions and ignores the force feedback information between the finger and the object. This control may be effective when grasping simple objects, but its limitations are obvious when facing complex or irregular objects.

[0004] In addition, some dexterous hand control systems use closed-loop control based on force sensors, which can monitor the force feedback information between fingers and objects in real time and adjust the control strategy. However, most of these systems use one-dimensional force tactile sensors and lack the ability to detect slippage. Even if three-dimensional force tactile sensors or multi-point array tactile sensors are used, their signal processing algorithms are relatively complex, and sometimes even require long-term training in combination with neural network models. For example, patent CN114474073A uses a one-dimensional pressure sensor, which requires a preset expected pressure value, and controls the dexterous hand to grasp through a PID algorithm until the output value of the pressure sensor reaches the preset value. This control mode cannot detect whether the object is grasped firmly or whether sliding occurs, resulting in a significant drop in the grasping success rate when the weight or shape of the object changes or is impacted, and cannot achieve functions such as adaptive grasping and drag teaching, limiting the ability of the dexterous hand to handle complex tasks.

[0005] In summary, the existing dexterous hand control system has the following problems:

[0006] First, the control strategies are mostly open-loop and cannot be adaptively adjusted according to the feedback information during the grasping process, which can easily lead to grasping failure or damage to the object.

[0007] Second, drag-and-drop teaching is not possible, and the action choreography lacks flexibility.

[0008] Third, the computing resources required are large and the energy consumption is high. Therefore, the existing dexterous hand control system still has a lot of room for improvement in terms of flexibility, accuracy and energy consumption. Summary of the invention

[0009] In order to solve the above technical problems, the present invention provides a dexterous hand control system and control method for multi-dimensional force tactile adaptive grasping, the control system includes a host computer, a dexterous hand master controller module, and three modules: a three-dimensional force tactile sensor module, a finger controller module and an actuator module independently configured for each finger of the dexterous hand;

[0010] The dexterous hand master controller module receives and analyzes the first control instruction from the host computer, and generates the second control instruction corresponding to each finger of the dexterous hand;

[0011] The three-dimensional force tactile sensor module monitors and acquires contact data between the finger and the target object;

[0012] The finger controller module performs the dexterous hand grasping task based on the second control instruction, calculates the target position that the servo motor controlled by the actuator module should reach at different time points by combining the contact data of the three-dimensional force tactile sensor module and the state feedback data of the actuator module, and generates a third control instruction according to the target position and sends it to the actuator module;

[0013] After receiving the third control instruction, the actuator module adjusts the position of the servo motor, and the servo motor drives the dexterous finger to complete the adaptive grasping action according to the predetermined trajectory and force.

[0014] In one embodiment of the present invention, the finger controller module calculates the target position that the servo motor controlled by the actuator module should reach at different time points based on the second control instruction, in combination with the contact data of the three-dimensional force tactile sensor module and the state feedback data of the actuator module, including:

[0015] The finger controller module receives the second control instruction to enable the fingers of the dexterous hand to perform a grasping task;

[0016] When the fingers of the dexterous hand touch an object, the force data of the fingers in the X, Y, and Z axes are obtained according to the three-dimensional force tactile sensor module on the fingers that touch the target object. The finger controller module calculates the maximum force value in the three axes and the maximum rate of change of the three-axis force value per unit time. According to the maximum rate of change of the three-axis force value per unit time, the grasping state of the fingers is judged at the same time:

[0017] If the maximum rate of change of the three-axis force value per unit time meets the preset conditions, the finger controller module switches from the finger grasping control mode to the force holding state, the position of the servo motor no longer changes, and the finger grasping is completed;

[0018] If the maximum rate of change of the three-axis force value within the unit time does not meet the preset conditions, based on the maximum force value among the three axes, the target position that the servo motor controlled by the actuator module should reach at different time points is obtained by continuously iteratively calculating;

[0019] Among them, the preset condition is: the maximum change rate of the three-axis force value within the unit time is less than the preset change rate threshold and the duration exceeds the preset time length.

[0020] In one embodiment of the present invention, if the maximum rate of change of the three-axis force value per unit time does not meet the preset conditions, the target position that the servo motor controlled by the actuator module should reach at different time points is obtained by continuously iteratively calculating based on the maximum force value among the three axes, including:

[0021] Calculate the finger force position joint speed according to the finger force position data obtained by the three-dimensional force tactile sensor module and the motor speed obtained by the actuator module;

[0022] Based on the maximum force value in the three axes and the joint velocity of the finger at the force position, calculate the target position of the joint at the force position in the next unit time;

[0023] According to the target position of the force-bearing position joint in the next unit time, the motor position in the next unit time, that is, the target position, is calculated. Based on the target position, the servo motor will move to the target position in the next unit time.

[0024] In one embodiment of the present invention, the target position of the force-bearing joint in the next unit time is calculated. :

[0025] ,

[0026] in, Indicates unit time, Indicates the maximum force value in the three axes, represents the virtual damping coefficient, Indicates the joint velocity of the finger force position, represents the virtual elastic coefficient, represents the virtual quality coefficient, Represents the virtual origin.

[0027] In one embodiment of the present invention, when the object grasped by the dexterous hand is impacted or slides due to the object's own gravity, the finger controller module calculates the maximum rate of change of the three-axis force value per unit time based on the feedback data of the three-dimensional force tactile sensor module, increases the elastic coefficient to increase the holding force of the dexterous hand, until the maximum rate of change of the three-axis force value per unit time meets the preset conditions.

[0028] In one embodiment of the present invention, the dexterous hand master controller module includes a fault detection and safety protection control module, which is connected to the host computer, the three-dimensional force tactile sensor module, and the actuator module. When the dexterous hand performs a grasping task, the temperature and maximum operating current of the actuator module are monitored in real time to see whether they exceed the allowable working conditions. At the same time, the maximum force value output by the three-dimensional force tactile sensor module is monitored in real time to see whether it exceeds the allowable maximum working output value. If a fault occurs, the module will be shut down in time and fault information will be sent to the host computer.

[0029] In one embodiment of the present invention, the dexterous hand master controller module includes a finger coordination control module, which parses the first control instruction from the host computer and generates a second control instruction corresponding to each dexterous hand finger. At the same time, when all the dexterous hand fingers cooperate to perform a grasping action, the distance between the fingers is calculated, the interference judgment result is obtained, and the obstacle avoidance between the fingers in the grasping action is completed according to the interference judgment result.

[0030] In one embodiment of the present invention, the actuator module includes a motor controller and an absolute encoder, and the state feedback data includes the operating temperature and current of the servo motor acquired by the motor controller, and the current speed and position of the servo motor acquired by the absolute encoder.

[0031] In one embodiment of the present invention, a plurality of finger controller modules are communicatively connected to the dexterous hand master controller module via the same IIC bus.

[0032] In one embodiment of the present invention, the host computer and the dexterous hand master controller module are connected via RS485 bus or CAN bus or EtherCAT bus.

[0033] Based on the same inventive concept, the present invention also provides a dexterous hand control method for multi-dimensional force tactile adaptive grasping, and the dexterous hand control system for multi-dimensional force tactile adaptive grasping is used to grasp the target object. The control method includes the following steps:

[0034] S1: receiving a first control instruction for executing a dexterous hand grasping task, and generating a second control instruction corresponding to the movement of each dexterous hand finger;

[0035] S2: monitoring and acquiring contact data between the finger and the target object, and based on the second control instruction, combining the contact data and the state feedback data of the servo motor driving the finger, calculating the target position that the driven finger should reach at different time points, and generating a third control instruction according to the target position;

[0036] S3: Based on the third control instruction, the position of the servo motor is adjusted, and the servo motor drives the dexterous finger to complete an adaptive grasping action according to a predetermined trajectory and force.

[0037] In one embodiment of the present invention, in S2, the method for calculating the target position that the driving finger should reach at different time points is as follows:

[0038] Obtain the force data of the finger in contact with the target object in the X, Y, and Z axes, calculate the maximum force value in the three axes and the maximum rate of change of the three-axis force value per unit time, and judge the grasping state of the finger based on the maximum rate of change of the three-axis force value per unit time:

[0039] If the maximum rate of change of the three-axis force value per unit time meets the preset conditions, the finger grasping control mode is switched to the force holding state, the position of the driving finger no longer changes, and the finger grasping is completed;

[0040] If the maximum rate of change of the three-axis force value per unit time does not meet the preset condition, the target position that the driving finger should reach at different time points is obtained by continuously iteratively calculating based on the maximum force value among the three axes;

[0041] Among them, the preset condition is: the maximum change rate of the three-axis force value within the unit time is less than the preset change rate threshold and the duration exceeds the preset time length.

[0042] In one embodiment of the present invention, if the maximum rate of change of the three-axis force value per unit time does not meet the preset condition, a method for iteratively calculating the target position that the driven finger should reach at different time points based on the maximum force value among the three axes is as follows:

[0043] Calculate the joint speed of the finger force position according to the acquired finger force position data and the current driving speed of the finger;

[0044] Based on the maximum force value in the three axes and the joint velocity of the finger at the force position, calculate the target position of the joint at the force position in the next unit time;

[0045] According to the target position of the force-bearing position joint in the next unit time, the driving position of the finger in the next unit time, that is, the target position, is calculated. Based on the target position, the finger will move to the target position in the next unit time.

[0046] In one embodiment of the present invention, the target position of the force-bearing joint in the next unit time is calculated. :

[0047] ,

[0048] in, Indicates unit time, Indicates the maximum force value in the three axes, represents the virtual damping coefficient, Indicates the joint velocity of the finger force position, represents the virtual elastic coefficient, represents the virtual quality coefficient, Represents the virtual origin.

[0049] The present invention also provides a computer storage medium storing a computer software product. The computer software product includes several instructions for enabling a computer device to execute the dexterous hand control method for multi-dimensional force tactile adaptive grasping.

[0050] The above technical solution of the present invention has the following advantages compared with the prior art:

[0051] 1. The present invention combines a three-dimensional force tactile sensor with a flexible force-position hybrid control algorithm to achieve closed-loop adaptive grasping control of the dexterous hand, significantly improving the flexibility and accuracy of the system. This innovation solves the problem of decreased grasping stability and accuracy caused by the difficulty of existing systems in handling complex tasks due to their difficulty in adapting to changes in object shape and material.

[0052] 2. The present invention adopts drag teaching based on three-dimensional force tactile sensors and a flexible impedance control strategy, without relying on precise mathematical models, thereby broadening the application scenarios and scope of the control algorithm.

[0053] 3. By optimizing the control algorithm, the present invention effectively reduces the power consumption of the actuator, prolongs the service life of the manipulator, and improves the energy efficiency of the entire system.

[0054] 4. The application of the present invention is not limited to five-finger dexterous hands, but is also applicable to other types of dexterous hands and mechanical grippers such as three-finger and four-finger hands, showing wide applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below according to specific embodiments of the present invention in conjunction with the accompanying drawings, wherein:

[0056] Figure 1 It is a schematic diagram of the structure of a dexterous hand control system for multi-dimensional force tactile adaptive grasping provided in one embodiment of the present invention;

[0057] Figure 2 It is a schematic diagram of the specific structure of a dexterous hand control system for multi-dimensional force tactile adaptive grasping provided in one embodiment of the present invention;

[0058] Figure 3is a flow chart of a closed-loop adaptive grasping control method based on a three-dimensional force tactile sensor in an embodiment of the present invention;

[0059] Figure 4 It is a flow chart of a method for hybrid control of admittance flexibility force and position in one embodiment of the present invention;

[0060] Figure 5 It is a communication architecture of a dexterous hand control system for multi-dimensional force tactile adaptive grasping in one embodiment of the present invention;

[0061] Figure 6 It is a schematic flow chart of a dexterous hand control method for multi-dimensional force tactile adaptive grasping provided in an embodiment of the present invention;

[0062] Explanation of the reference numerals in the specification: 10. Host computer; 20. Dexterous hand master controller module; 21. Fault detection and safety protection control module; 22. Finger coordination control module; 23. Communication module; 30. Three-dimensional force tactile sensor module; 40. Finger controller module; 50. Actuator module; 51. Motor controller; 52. Absolute encoder. DETAILED DESCRIPTION

[0063] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention. Embodiment 1

[0064] like Figure 1 and Figure 2 As shown, the present invention provides a dexterous hand control system for multi-dimensional force tactile adaptive grasping, the system comprising a host computer 10, a dexterous hand master controller module 20, and three modules, namely, a three-dimensional force tactile sensor module 30, a finger controller module 40 and an actuator module 50, which are independently configured for each finger of the dexterous hand;

[0065] The dexterous hand master controller module 20 receives and analyzes the first control instruction from the host computer, and generates the second control instruction corresponding to each finger of the dexterous hand;

[0066] The three-dimensional force tactile sensor module 30 monitors and acquires contact data between the finger and the target object;

[0067] The finger controller module 40 performs the dexterous hand grasping task based on the second control instruction, calculates the target position that the servo motor controlled by the actuator module 50 should reach at different time points by combining the contact data of the three-dimensional force tactile sensor module 30 and the state feedback data of the actuator module 50, and generates a third control instruction according to the target position and sends it to the actuator module 50;

[0068] After receiving the third control instruction, the actuator module 50 adjusts the position of the servo motor, and the servo motor drives the dexterous finger to complete the adaptive grasping action according to the predetermined trajectory and force.

[0069] It can be seen from the above technical solution that the present invention monitors the contact data between the finger and the target object in real time through the three-dimensional force tactile sensor module 30, and the finger controller module 40 can combine these data and the state feedback of the actuator module 50 to accurately calculate the target position that the servo motor should reach and generate corresponding control instructions. This precise control method enables the dexterous hand to adaptively adjust the grasping force and speed according to different situations, ensuring the accuracy and stability of the grasping action.

[0070] Each finger is independently equipped with a three-dimensional force tactile sensor module 30, a finger controller module 40 and an actuator module 50, realizing independent control of multiple fingers. This design enables the dexterous hand to cope with complex grasping tasks more flexibly, and improves grasping efficiency and success rate through collaborative work between fingers.

[0071] Combination Figure 3 and Figure 4 The following is a schematic diagram of the closed-loop adaptive control method based on the three-dimensional force tactile sensor to control the working principle of the dexterous hand to grasp:

[0072] When the dexterous hand master controller module 20 receives the first control instruction from the host computer 10, it sends a loading instruction to the finger controller module 40 after task decomposition, and the dexterous hand fingers will switch from the reset static state to the admittance flexibility force position mixed control state.

[0073] Furthermore, when the fingers of the dexterous hand do not touch the object, under the action of the initial parameters, the servo motor drives the fingers of the dexterous hand to bend and move toward the target object at a constant speed.

[0074] When the finger of the dexterous hand contacts an object, the finger controller module 40 adjusts the position of the servo motor controlled by the actuator module 50 according to the contact data fed back in real time by the three-dimensional force tactile sensor module 30 at the contact position. At this time, the finger controller module 40 calculates the movement of the servo motor to the target position in different unit times, and the method is as follows:

[0075] According to the three-dimensional force tactile sensor module 30 on the finger in contact with the target object, the force data of the finger in the X, Y and Z axes are obtained. The finger controller module 40 calculates the maximum force value in the three axes and unit time ( ) Maximum rate of change of the triaxial force value , according to the maximum rate of change of the triaxial force value per unit time , judge the grasping state of the finger:

[0076] If the maximum rate of change of the triaxial force value per unit time When the preset conditions of the change rate being less than the preset threshold value (0.01N / ms) and the duration T exceeding the preset duration (500ms) are met, the finger controller module 40 switches from the finger grasping control mode to the force holding state, the position of the servo motor no longer changes, and the finger grasping is completed; in the force holding state, the data changes of the three-dimensional force tactile sensor module 30 are still continuously monitored;

[0077] If the maximum rate of change of the triaxial force value per unit time The preset conditions are not met, based on the maximum force value in the three axes The target position that the servo motor controlled by the actuator module 50 should reach at different time points is calculated by continuously iteratively using the admittance flexible force-position hybrid control method, so as to update the speed of the servo motor until the maximum rate of change of the three-axis force value per unit time is met. The preset conditions are met.

[0078] The method steps for using the admittance-flexible force-position hybrid control method to iteratively calculate the target position that the servo motor controlled by the actuator module 50 should reach at different time points are as follows:

[0079] According to the finger force position data obtained by the three-dimensional force tactile sensor module 30 and the motor speed obtained by the actuator module, the finger force position joint speed V is calculated by the robot kinematics DH algorithm;

[0080] Based on the initialization parameters such as the virtual origin, the maximum force value in the three axes The finger force position joint velocity V is used to calculate the next unit time target position of the force position joint using the admittance flexible force-position hybrid control core algorithm based on the second-order time-invariant BMK system model. :

[0081] ,

[0082] in, Indicates unit time, Indicates the maximum force value in the three axes, represents the virtual damping coefficient, Indicates the joint velocity of the finger force position, represents the virtual elastic coefficient, represents the virtual quality coefficient, represents the virtual origin;

[0083] The target position of the joint at the force position in the next unit time , calculate the motor position in the next unit time, that is, the target position. Based on the target position, the servo motor will move to the target position in the next unit time. By continuously executing the above steps in a cycle, the system realizes the hybrid control of admittance, flexibility, force and position, so as to flexibly and accurately control the grasping action of the dexterous hand.

[0084] When the object grasped by the dexterous hand is impacted or slides due to the object's own gravity, the finger controller module 40 will perform the following processing based on the real-time feedback data provided by the three-dimensional force tactile sensor module 30: First, calculate the maximum rate of change of the three-axis force value (i.e., the force in the X, Y, and Z axis directions) per unit time. Then, the system determines whether the maximum rate of change meets the preset stable grasping condition, that is, whether it is less than or equal to 0.01N / ms. Once it is determined that the current maximum rate of change does not meet this condition (i.e., the rate of change is greater than 0.01N / ms), it indicates that the grasping state is unstable, and the force holding mode will automatically switch to the admittance flexibility force position hybrid control mode.

[0085] After switching to the admittance-flexibility-force-position hybrid control mode, the system will dynamically adjust the elastic coefficient according to the maximum rate of change of the three-axis force value per unit time currently detected. Specifically, as the maximum rate of change increases, the elastic coefficient is increased accordingly to enhance the gripping force of the dexterous hand, thereby effectively suppressing the sliding tendency of the object. This process continues until the maximum rate of change of the three-axis force value per unit time meets the preset stable grasping condition again, that is, the rate of change is reduced to 0.01N / ms and lasts for 500ms.

[0086] Through the above mechanism, the dexterous hand can achieve adaptive adjustment to different complex grasping situations, significantly improving its stable grasping ability in various environments.

[0087] Furthermore, the dexterous hand master controller module 20 includes a fault detection and safety protection control module 21, a finger coordination control module 22 and a communication module 23. The communication module 23 is connected to the host computer 10, the three-dimensional force tactile sensor module 30 and the actuator module 50. The communication module 23 is responsible for receiving and transmitting control command data of other components to ensure an efficient communication and coordination mechanism between systems. It also assumes the responsibility of remotely monitoring and controlling the dexterous hand for the host computer 10, and its functions include programming of preset action sequences, realization of adaptive admittance control mode and provision of drag-and-drop teaching functions.

[0088] Among them, the fault detection and safety protection control module 21 is connected to the communication module 23. During the process of the dexterous hand performing the grasping task, it monitors in real time whether the temperature and maximum operating current of the actuator module 50 exceed the allowable working conditions. At the same time, it monitors in real time whether the maximum force value output by the three-dimensional force tactile sensor module 30 exceeds the allowable maximum working output value. If a fault occurs, it will shut down in time and send fault information to the host computer 10.

[0089] The finger coordination control module 22 is connected to the communication module 23, and parses the first control instruction from the host computer 10 to generate a second control instruction corresponding to each finger of the dexterous hand. At the same time, when all the dexterous hand fingers cooperate to perform a grasping action, the distance between the fingers is calculated through a spatial interference detection algorithm, and an interference judgment result is obtained. According to the interference judgment result, obstacle avoidance between each finger in the grasping action is completed.

[0090] Furthermore, the actuator module 50 includes a motor controller 51 and an absolute encoder 52 both connected to the servo motor, and the state feedback data includes the operating temperature and current of the servo motor obtained by the motor controller 51 and the current speed and position of the servo motor obtained by the absolute encoder 52 .

[0091] In such Figure 5 In the communication architecture of the dexterous hand control system shown, the communication between the dexterous hand master controller module 20 and the host computer 10 supports three high-performance communication protocols: RS485, CAN bus, and EtherCAT. In addition, the dexterous hand master controller module 20 is also equipped with API (application programming interface), ROS (robot operating system) and ROS2 interface for users to conduct in-depth secondary development, thereby greatly improving the scalability and maintainability of the system.

[0092] The IIC (two-wire serial bus) communication protocol is used between the dexterous hand master controller module 20 and the finger controller module 40. This design enables the finger controller modules 40 deployed on multiple fingers to share the same IIC bus, which not only simplifies the wiring complexity of the control system, but also effectively reduces the number of I / O (input / output) pins required by the dexterous hand master controller module 20.

[0093] The system also uses the IIC bus for communication between the three-dimensional force tactile sensor module 30 and the finger controller module 40. This approach allows multiple three-dimensional force tactile sensor modules 30 to be easily mounted on the same IIC bus, further saving I / O pin resources of the finger controller module 40.

[0094] At the level of the actuator module 50, the motor controller 51 and the absolute encoder 52 communicate with the finger controller module 40 via the SPI (Serial Peripheral Interface) bus. The SPI bus ensures efficient data transmission between the motor controller 51, the absolute encoder 52 and the finger controller module 40 with its high-speed, full-duplex and synchronous communication characteristics.

[0095] It should be noted that the dexterous hand of any structural form of the present invention has excellent drag-and-drop teaching capabilities, which allows the user to easily and flexibly arrange the dexterous hand movements through an intuitive dragging method.

[0096] When the host computer is switched to the drag teaching mode, the elastic coefficient in the admittance flexible force-position hybrid control will be automatically set to 0 to ensure that the dexterous hand fingers can follow the human hand movements without hindrance during the dragging process. At this time, the user can pinch the side of the tactile sensor installed on the dexterous hand fingers (i.e., the X / Y axis force area) with the index finger and thumb of both hands, and guide the dexterous hand fingers to teach the grasping action by applying appropriate force. Similarly, when the user presses the front of the tactile sensor (i.e., the Z axis force area) with his fingers, the dexterous hand finger extension teaching can be controlled. The grasping teaching here refers to bending the dexterous hand fingers to simulate the grasping action, while the extension teaching is to reset the fingers to the straight state.

[0097] After dragging the dexterous hand finger to the desired position, the user can record the current teaching point on the host computer and set the speed to move from the previous position to this point. By repeating this operation, the user can continuously record multiple sets of teaching points, thereby gradually building a complete action sequence.

[0098] Once the action choreography is completed, the user only needs to save the teaching point information on the host computer, and the dexterous hand can automatically perform the choreographed actions according to the preset teaching point sequence. This drag-and-drop teaching method not only simplifies the programming process of the dexterous hand, but also greatly improves the flexibility and accuracy of action choreography, allowing users to easily customize various complex operation tasks for the dexterous hand.

[0099] In summary, compared with the prior art, the present invention not only improves the grasping accuracy and adaptability of the dexterous hand, simplifies the system structure, reduces costs, enhances the flexibility and safety of the system, but also improves the adaptability and robustness of the control algorithm, reduces energy consumption, and has significant advantages. Embodiment 2

[0100] Based on the same inventive concept as that of the first embodiment, the present invention also provides a dexterous hand control method for multi-dimensional force tactile adaptive grasping, and the dexterous hand control system for multi-dimensional force tactile adaptive grasping described in the first embodiment is used to grasp the target object. Figure 6As shown, the control method comprises the following steps:

[0101] S1: receiving a first control instruction for executing a dexterous hand grasping task, and generating a second control instruction corresponding to the movement of each dexterous hand finger;

[0102] S2: monitoring and acquiring contact data between the finger and the target object, and based on the second control instruction, combining the contact data and the state feedback data of the servo motor driving the finger, calculating the target position that the driven finger should reach at different time points, and generating a third control instruction according to the target position;

[0103] S3: Based on the third control instruction, the position of the servo motor is adjusted, and the servo motor drives the dexterous finger to complete an adaptive grasping action according to a predetermined trajectory and force.

[0104] Furthermore, in step S2, the method for calculating the target position that the driving finger should reach at different time points is as follows:

[0105] Get the force data of the finger in contact with the target object in the X, Y, and Z axes , calculate the maximum force value in the three axes and unit time ( ) Maximum rate of change of the triaxial force value , according to the maximum rate of change of the triaxial force value per unit time , judge the grasping state of the finger:

[0106] If the maximum rate of change of the triaxial force value per unit time When the preset conditions are met, that the change rate is less than the preset threshold value (0.01N / ms) and the duration T exceeds the preset time (500ms), the finger grasping control mode is switched to the force holding state, the position of the driving finger no longer changes, and the finger grasping is completed;

[0107] If the maximum rate of change of the triaxial force value per unit time The preset conditions are not met, based on the maximum force value in the three axes , and continuously iteratively calculate the target position that the driving finger should reach at different time points, including:

[0108] According to the acquired finger force position data and the current driving finger speed, the finger force position joint speed V is calculated by the robot kinematics DH algorithm;

[0109] Based on the largest force value among the three axes The finger force position joint velocity V is used to calculate the next unit time target position of the force position joint using the admittance flexible force-position hybrid control core algorithm based on the second-order time-invariant BMK system model. :

[0110] ,

[0111] in, Indicates unit time, Indicates the maximum force value in the three axes, represents the virtual damping coefficient, Indicates the joint velocity of the finger force position, represents the virtual elastic coefficient, represents the virtual quality coefficient, represents the virtual origin;

[0112] The target position of the joint at the force position in the next unit time , calculate the driving position of the servo motor in the next unit time, that is, the target position, and the servo motor drives the finger to move toward the target position in the next unit time according to the target position. Embodiment 3

[0113] The present invention also provides a computer storage medium storing a computer software product. The computer software product includes several instructions for enabling a computer device to execute the dexterous hand control method for multi-dimensional force tactile adaptive grasping described in Example 2.

[0114] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0115] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0116] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0117] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0118] Obviously, the above embodiments are merely examples for clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the protection scope of the invention.

Claims

1. A dexterous hand control system for multi-dimensional force tactile adaptive grasping, characterized in that: The control system includes a host computer, a dexterous hand master controller module, and three modules: a three-dimensional force tactile sensor module, a finger controller module and an actuator module independently configured for each finger of the dexterous hand; The dexterous hand master controller module receives and analyzes the first control instruction from the host computer, and generates the second control instruction corresponding to each finger of the dexterous hand; The three-dimensional force tactile sensor module monitors and acquires contact data between the finger and the target object; The finger controller module performs the dexterous hand grasping task based on the second control instruction, calculates the target position that the servo motor controlled by the actuator module should reach at different time points by combining the contact data of the three-dimensional force tactile sensor module and the state feedback data of the actuator module, and generates a third control instruction according to the target position and sends it to the actuator module; After receiving the third control instruction, the actuator module adjusts the position of the servo motor, and the servo motor drives the dexterous finger to complete the adaptive grasping action according to the predetermined trajectory and force; The finger controller module calculates the target position that the servo motor controlled by the actuator module should reach at different time points based on the second control instruction, in combination with the contact data of the three-dimensional force tactile sensor module and the state feedback data of the actuator module, including: The finger controller module receives the second control instruction to enable the fingers of the dexterous hand to perform a grasping task; When the fingers of the dexterous hand touch an object, the force data of the fingers in the X, Y, and Z axes are obtained according to the three-dimensional force tactile sensor module on the fingers that touch the target object. The finger controller module calculates the maximum force value in the three axes and the maximum rate of change of the three-axis force value per unit time. According to the maximum rate of change of the three-axis force value per unit time, the grasping state of the finger is judged: If the maximum rate of change of the three-axis force value per unit time meets the preset conditions, the finger controller module switches from the finger grasping control mode to the force holding state, the position of the servo motor no longer changes, and the finger grasping is completed; If the maximum rate of change of the three-axis force value per unit time does not meet the preset conditions, the target position that the servo motor controlled by the actuator module should reach at different time points is obtained by continuously iteratively calculating based on the maximum force value among the three axes, including: Calculate the finger force position joint speed according to the finger force position data obtained by the three-dimensional force tactile sensor module and the motor speed obtained by the actuator module; Based on the maximum force value in the three axes and the speed of the finger joint at the force position, the target position Target_X of the joint at the force position in the next unit time is calculated: Among them, dt represents unit time, F represents the maximum force value in the three axes, DAMPING represents the virtual damping coefficient, V represents the joint velocity of the finger force position, STIFFNESS represents the virtual elastic coefficient, MASS represents the virtual mass coefficient, and origin_X represents the virtual origin; According to the target position of the joint at the force position at the next unit time, the motor position at the next unit time, i.e., the target position, is calculated. Based on the target position, the servo motor will move toward the target position in the next unit time. Among them, the preset condition is: the maximum change rate of the three-axis force value within the unit time is less than the preset change rate threshold and the duration exceeds the preset time length.

2. The dexterous hand control system for multi-dimensional force tactile adaptive grasping according to claim 1 is characterized in that: When the object grasped by the dexterous hand is impacted or slides due to the object's own gravity, the finger controller module calculates the maximum rate of change of the three-axis force value per unit time based on the feedback data of the three-dimensional force tactile sensor module, increases the elastic coefficient to increase the holding force of the dexterous hand, until the maximum rate of change of the three-axis force value per unit time meets the preset conditions.

3. The multi-dimensional force tactile adaptive grasping dexterous hand control system according to claim 1 is characterized in that: The dexterous hand master controller module includes a fault detection and safety protection control module, which is connected to the host computer, the three-dimensional force tactile sensor module, and the actuator module. When the dexterous hand performs a grasping task, the temperature and maximum operating current of the actuator module are monitored in real time to see if they exceed the allowable working conditions. At the same time, the maximum force value output by the three-dimensional force tactile sensor module is monitored in real time to see if it exceeds the allowable maximum working output value. If a fault occurs, the module will be shut down in time and fault information will be sent to the host computer.

4. The multi-dimensional force tactile adaptive grasping dexterous hand control system according to claim 1 is characterized in that: The dexterous hand master controller module includes a finger coordination control module, which parses the first control instruction from the host computer and generates a second control instruction corresponding to each dexterous hand finger. At the same time, when all the dexterous hand fingers cooperate to perform a grasping action, the distance between the fingers is calculated, the interference judgment result is obtained, and the obstacle avoidance between the fingers in the grasping action is completed according to the interference judgment result.

5. The multi-dimensional force tactile adaptive grasping dexterous hand control system according to claim 1 is characterized in that: The actuator module includes a motor controller and an absolute value encoder, and the state feedback data includes the operating temperature and current of the servo motor acquired by the motor controller, and the current speed and position of the servo motor acquired by the absolute value encoder.

6. The multi-dimensional force tactile adaptive grasping dexterous hand control system according to claim 1 is characterized in that: A plurality of finger controller modules are communicatively connected to the dexterous hand master controller module via the same IIC bus.

7. The multi-dimensional force tactile adaptive grasping dexterous hand control system according to claim 1 is characterized in that: The host computer and the dexterous hand master controller module are connected via RS485 bus, CAN bus or EtherCAT bus communication.

8. A dexterous hand control method for multi-dimensional force tactile adaptive grasping, characterized in that: The target object is grasped by using the dexterous hand control system for multi-dimensional force tactile adaptive grasping as claimed in any one of claims 1 to 7, wherein the control method comprises the following steps: S1: receiving a first control instruction for executing a dexterous hand grasping task, and generating a second control instruction corresponding to the movement of each dexterous hand finger; S2: monitoring and acquiring contact data between the finger and the target object, and based on the second control instruction, combining the contact data and the state feedback data of the servo motor driving the finger, calculating the target position that the driven finger should reach at different time points, and generating a third control instruction according to the target position; S3: Based on the third control instruction, the position of the servo motor is adjusted, and the servo motor drives the dexterous finger to complete an adaptive grasping action according to a predetermined trajectory and force.

9. The dexterous hand control method for multi-dimensional force tactile adaptive grasping according to claim 8, characterized in that: In S2, the method for calculating the target position that the driven finger should reach at different time points is as follows: Obtain the force data of the finger in contact with the target object in the X, Y, and Z axes, calculate the maximum force value in the three axes and the maximum rate of change of the three-axis force value per unit time, and judge the grasping state of the finger based on the maximum rate of change of the three-axis force value per unit time: If the maximum rate of change of the three-axis force value per unit time meets the preset conditions, the finger grasping control mode is switched to the force holding state, the position of the driving finger no longer changes, and the finger grasping is completed; If the maximum rate of change of the three-axis force value per unit time does not meet the preset condition, the target position that the driving finger should reach at different time points is obtained by continuously iteratively calculating based on the maximum force value among the three axes; Among them, the preset condition is: the maximum change rate of the three-axis force value within the unit time is less than the preset change rate threshold and the duration exceeds the preset time length.

10. The dexterous hand control method for multi-dimensional force tactile adaptive grasping according to claim 9, characterized in that: If the maximum rate of change of the three-axis force value per unit time does not meet the preset conditions, the method of iteratively calculating the target position that the driven finger should reach at different time points based on the maximum force value among the three axes is as follows: Calculate the joint speed of the finger force position according to the acquired finger force position data and the current driving speed of the finger; Based on the maximum force value in the three axes and the joint velocity of the finger at the force position, calculate the target position of the joint at the force position in the next unit time; According to the target position of the force-bearing position joint in the next unit time, the driving position of the finger in the next unit time, that is, the target position, is calculated. Based on the target position, the finger will move to the target position in the next unit time.

11. The dexterous hand control method for multi-dimensional force tactile adaptive grasping according to claim 10, characterized in that: Calculate the target position Target_X of the force position joint in the next unit time: Among them, dt represents unit time, F represents the maximum force value in the three axes, DAMPING represents the virtual damping coefficient, V represents the joint velocity of the finger force position, STIFFNESS represents the virtual elastic coefficient, MASS represents the virtual mass coefficient, and origin_X represents the virtual origin.

12. A computer storage medium, characterized in that: The computer storage medium stores a computer software product, which includes several instructions for enabling a computer device to execute the dexterous hand control method for multi-dimensional force tactile adaptive grasping as described in any one of claims 9 to 11.

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