Man-machine cooperation carrying control method and system and electronic equipment

Abstract

The invention provides a man-machine cooperation carrying control method and system and electronic equipment, and the method comprises the steps: calculating an expected normal force applied to a target carrying object by a robot, and obtaining a real-time normal force on the target carrying object through the measurement of a sensor; based on the expected normal force and the real-time normal force, a control normal force which should be applied is calculated. And based on the set reference trajectory and the detected external force, calculating to obtain a resultant acceleration, determining an expected trajectory according to the resultant acceleration, and obtaining an impedance control force based on the external force and the expected trajectory through an impedance controller. And the control torque of the robot is calculated by combining the control normal force and the impedance control force. According to the scheme, the influence of the external force is considered while the expected trajectory is tracked, so that the purpose of keeping the control comfort while target deviation is avoided is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of robot control, in particular to a human-robot collaborative carrying control method, system and electronic device. BACKGROUND

[0002] With the development of human-robot collaboration technology, object carrying has become one of the important application scenarios in physical human-robot collaboration (PHRC). In this task, the human and the robot jointly act on the same object, and need to realize coordinated control of position and force in a dynamic environment. Especially in the process of collaborative carrying, in order to ensure the stability of the object, it is necessary to maintain the contact force with the object and respond to the operation intention of the human in real time, so as to realize smooth, safe and efficient collaboration.

[0003] At present, the commonly used interactive control methods include impedance control and compliance control, among which the compliance control is widely used in human-robot interaction because it is easy to implement and does not depend on joint force sensors.

[0004] However, the existing methods mostly focus on the passive response of the robot to the human intention, and lack the ability to actively guide the human back to the desired trajectory. In actual carrying tasks, if the human operation is always followed, the target may deviate; while completely rigid trajectory tracking will reduce the operation comfort of the human. Therefore, while maintaining the human dominance, it is necessary to realize the appropriate guidance of the robot to the human when necessary, which is a problem that has not been effectively solved in the current technology. In addition, most researches assume that the object and the robot flange are rigidly connected, ignoring the challenge of maintaining contact stability in actual applications, which limits the applicability of the system in real carrying scenarios. SUMMARY

[0005] The purpose of the embodiments of the present application is to provide a human-robot collaborative carrying control method, system and electronic device, which can avoid target deviation while maintaining operation comfort.

[0006] In a first aspect, the present application provides a human-robot collaborative carrying control method, which comprises: calculating a desired normal force exerted by a robot on a target carrying object; measuring a real-time normal force on the target carrying object through a sensor; calculating a control normal force that should be exerted based on the desired normal force and the real-time normal force; calculating a resultant acceleration based on a set reference trajectory and a detected external force; determining a desired trajectory according to the resultant acceleration, and obtaining an impedance control force based on the external force and the desired trajectory through an impedance controller; combining the control normal force and the impedance control force to calculate a control torque of the robot.

[0007] In an optional embodiment, the step of calculating the desired normal force applied by the robot to the target object includes: obtaining a rotation matrix of an end effector coordinate system of the robot relative to a base coordinate system; determining a normal contact force direction applied by the end effector to the target object based on the rotation matrix; calculating an included angle between the normal contact force direction and a vertical upward vector; calculating a desired normal force based on the normal contact force direction, the included angle, a friction coefficient, and a gravity force acting on the target object.

[0008] In an optional embodiment, the step of calculating the control normal force to be applied based on the desired normal force and the real-time normal force includes: calculating the control normal force at a next time point using a PI control method according to the desired normal force and the real-time normal force at each time point; performing curve fitting based on the control normal force at each time point within a force control period to obtain a variation curve of the control normal force; determining the control normal force to be applied at each time point based on the variation curve.

[0009] In an optional embodiment, the step of calculating the resultant acceleration based on the set reference trajectory and the detected external force includes: obtaining a first acceleration reflecting an influence of the external force according to the detected external force; obtaining a second acceleration reflecting an influence of the tracking trajectory according to the set reference trajectory; calculating a resultant acceleration based on the first acceleration, the second acceleration, and an acceleration adjustment factor.

[0010] In an optional embodiment, the step of obtaining the second acceleration reflecting the influence of the tracking trajectory according to the set reference trajectory includes: constructing a state equation of an end effector of the robot, and constructing an acceleration sequence at each time point based on the state equation; determining a corresponding state sequence based on the acceleration input sequence; constructing a cost function of motion based on the set reference trajectory and the state sequence; solving the acceleration sequence in the cost function, and obtaining the second acceleration reflecting the influence of the tracking trajectory based on the solved acceleration sequence.

[0011] In an optional embodiment, the step of obtaining the impedance control force by the impedance controller based on the external force and the desired trajectory includes: According to the relationship between the joint space dynamics equation and the Cartesian space dynamics equation, a complete Cartesian space dynamics equation is obtained to construct an impedance controller under the complete Cartesian space dynamics equation; The impedance control force is calculated by the impedance controller based on the external force and the desired trajectory.

[0012] In an optional embodiment, the desired trajectory includes a desired pose, a desired velocity, and a desired acceleration; The step of calculating the impedance control force by the impedance controller based on the external force and the desired trajectory includes: According to the desired pose, the desired velocity, and the desired acceleration in the desired trajectory, and the obtained actual pose, actual velocity, and actual acceleration, a position difference, a velocity difference, and an acceleration difference are calculated; A closed-loop relationship between the external force, the position difference, the velocity difference, the acceleration difference, and the desired matrix of the impedance control in the Cartesian space is constructed by the impedance controller; Based on the external force satisfying the closed-loop relationship and the desired trajectory, the impedance control force is calculated.

[0013] In an optional embodiment, the step of calculating the control torque of the robot by combining the control normal force and the impedance control force includes: Based on the impedance control force and the control normal force, a total control force is calculated; According to the total control force and the Jacobian matrix, the control torque of the robot is calculated.

[0014] In a second aspect, the present application provides a human-robot collaborative carrying control system, which comprises: A first calculation module for calculating a desired normal force applied by a robot to a target carrying object; A measurement module for measuring a real-time normal force on the target carrying object through a sensor; A second calculation module for calculating a control normal force that should be applied based on the desired normal force and the real-time normal force; A third calculation module for calculating a synthetic acceleration based on a set reference trajectory and a detected external force; A determination module for determining a desired trajectory according to the synthetic acceleration, and obtaining an impedance control force by an impedance controller based on the external force and the desired trajectory; A calculation control module for calculating a control torque of the robot by combining the control normal force and the impedance control force.

[0015] In a third aspect, the present application provides an electronic device comprising one or more storage media and one or more processors in communication with the storage media, the one or more storage media storing machine executable instructions executable by the processor, when the electronic device is running, the processor executes the machine executable instructions to perform the method of any one of the preceding embodiments.

[0016] The present application provides a human-robot collaborative carrying control method, system and electronic device, through a computer robot, a desired normal force applied to a target carrying object, a real-time normal force measured by a sensor. Based on the desired normal force and the real-time normal force, the control normal force to be applied is calculated. Based on the set reference trajectory and the detected external force, the synthesized acceleration is calculated, the desired trajectory is determined according to the synthesized acceleration, and the impedance control force is obtained by the impedance controller based on the external force and the desired trajectory. The control torque of the robot is calculated by combining the control normal force and the impedance control force. In the scheme, while tracking the desired trajectory, the influence of the external force is considered, so as to achieve the purpose of avoiding the target from deviating while maintaining the comfort of operation. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments of the present application. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0018] Figure 1 The flow chart of the human-robot collaborative carrying control method provided by the embodiments of the present application; Figure 2 The implementation logic diagram of the human-robot collaborative carrying control method provided by the embodiments of the present application; Figure 3 The curve diagram of displacement changing with time in the embodiments of the present application; Figure 4 The curve diagram of force changing with time in the embodiments of the present application; Figure 5 The functional module block diagram of the human-robot collaborative carrying control system provided by the embodiments of the present application; Figure 6 The structural block diagram of the electronic device provided by the embodiments of the present application. DETAILED DESCRIPTION

[0019] The technical solutions of the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application.

[0020] Please refer to Figure 1A flowchart of a human-robot collaborative carrying control method is provided for an embodiment of the present application. The human-robot collaborative carrying control method can be executed by a human-robot collaborative carrying control system, which can be implemented by software and / or hardware and can be configured in an electronic device, which can be a computer device, a server, or the like, for example, a server in a back-end control platform. The detailed steps of the human-robot collaborative carrying control method are described as follows.

[0021] S11, calculating a desired normal force applied by a robot to a target carrying object.

[0022] S12, measuring a real-time normal force on the target carrying object by a sensor.

[0023] S13, calculating a control normal force to be applied based on the desired normal force and the real-time normal force.

[0024] S14, calculating a resultant acceleration based on a set reference trajectory and a detected external force.

[0025] S15, determining a desired trajectory according to the resultant acceleration and obtaining an impedance control force based on the external force and the desired trajectory by an impedance controller.

[0026] S16, calculating a control torque of the robot in combination with the control normal force and the impedance control force.

[0027] In the embodiment, the target carrying object can be an object such as a box or goods that needs to be carried. The present solution is applied in a carrying scenario in which a robot performs carrying of a target carrying object. In the carrying scenario, the target carrying object is also subjected to an external force, which is mainly a human-provided external force to achieve collaborative carrying.

[0028] In the collaborative carrying scenario of the embodiment, the human does not provide a support force in the vertical direction, and the force applied by the human is only used to maintain the movement of the target carrying object in the plane, that is, the human does not share the force in the direction of gravity.

[0029] In the carrying process, the minimum normal contact force applied by the robot to the target carrying object should ensure that the target carrying object will not slide down due to gravity. The minimum normal contact force is the desired normal force. The step of calculating the desired normal force applied by the robot to the target carrying object can be implemented in the following manner: obtaining a rotation matrix of an end effector coordinate system of the robot relative to a base coordinate system; determining a normal contact force direction applied by the end effector to the target carrying object based on the rotation matrix; calculating an included angle between the normal contact force direction and a vertical upward vector; and calculating the desired normal force based on the normal contact force direction, the included angle, a friction coefficient, and a gravity suffered by the target carrying object.

[0030] Combining Figure 2 In this embodiment, it is assumed that {e} and {b} represent the end effector coordinate frame and the base coordinate frame of the robot manipulator, respectively. The rotation of {e} with respect to {b} is represented by the rotation matrix According to the usual definition, the direction of the z-axis of the {e} coordinate frame is the direction in which the end effector of the robot manipulator extends outward. Thus, the direction of the normal contact force exerted by the end effector on the target carrying object can be calculated based on the rotational torque and according to the following formula:

[0031] The direction of the normal contact force is represented by the angle between the vertical upward vector and the direction of the normal contact force. The direction of the normal contact force is represented by the angle between the vertical upward vector and the direction of the normal contact force. The force exerted by the robot manipulator on the target carrying object can be divided into two parts: the pressure and the static friction force. The magnitude of the normal force is represented by the scalar Because the upper limit of the friction force is determined by the normal force, assuming that the friction coefficient is , the maximum gravity compensation provided is:

[0032] Because the direction can be obtained by real-time calculation of forward kinematics, in the case where the gravity of the target carrying object is known, the expected normal force can be obtained based on the direction of the normal contact force, the angle, the friction coefficient, and the gravity of the target carrying object according to the following formula:

[0033] where is the magnitude of the gravity of the target carrying object.

[0034] In this way, the expected normal force exerted by the robot on the target carrying object can be obtained.

[0035] In addition, the real-time normal force on the target carrying object is measured by a force-torque (F / T) sensor installed at the end of the robot manipulator.

[0036] Based on the expected normal force and the real-time normal force, the tracking expected force is performed using feedback force error, so as to control the normal contact force. Specifically, the step of calculating the control normal force that should be exerted based on the expected normal force and the real-time normal force can be realized in the following way: According to the expected normal force and the real-time normal force at each time point, a PI control mode is adopted to calculate the control normal force at the next time point; a curve fitting is performed based on the control normal force at each time point in the force control period to obtain a change curve of the control normal force; and the control normal force that should be applied at each time point is determined based on the change curve.

[0037] Because different postures are generated in the carrying process, the expected normal force also changes differently. In this embodiment, a PI control mode is adopted to calculate the control normal force at the next time point, and the calculation formula is as follows:

[0038] wherein, K p , K i respectively represent a proportional coefficient and an integral coefficient, is the control normal force at the next time point.

[0039] In addition, at the beginning of carrying, the change of the contact force needs to be increased from zero, and the expected normal force suddenly changes from 0 to the gravity that can be supported. The PI controller will cause a sudden change of the contact instantaneous force, therefore, in order to maintain a smooth force interaction in the carrying process and prevent sudden changes of the force, in this embodiment, a cubic polynomial is introduced to smoothly transition the control normal force at the beginning of carrying. The introduced cubic polynomial is as follows:

[0040] At the beginning of carrying, the control normal force at the beginning of carrying is obtained by solving the following equation:

[0041] wherein, is 0, indicating the starting moment of the force control period, is 1, indicating the change time of the entire cubic polynomial curve, indicating the normal force at the beginning of the cubic polynomial fitting. When the carrying is to be stopped, a sudden change to 0 is also generated, and is expressed as:

[0042] ​Thus, in each force control cycle, the control normal force at each time point can be curve fitted to obtain a change curve. Then, the control normal force to be applied at each time point is determined based on the values in the change curve. Thus, the smooth transition of the control normal force at the beginning and end of the force control cycle can be realized, and the phenomenon of sudden change of force can be avoided.

[0043] Due to the existence of the man-machine collaborative framework, it is necessary to introduce compliant control. The compliance of force interaction is realized by impedance control, which prevents rigid force interaction by simulating a mass-spring-damper system in Cartesian space. The impedance controller obtains impedance control force based on external force and desired trajectory.

[0044] Since the mechanical arm needs to cooperate with the action of the person during the carrying process, while trying to track the preset trajectory. Therefore, the desired trajectory is affected by the external force of the person and the preset trajectory of the mechanical arm.

[0045] Based on this, in the embodiment, based on the set reference trajectory and the detected external force, a synthetic acceleration is obtained, and the desired trajectory is determined according to the synthetic acceleration.

[0046] Specifically, the step of obtaining the synthetic acceleration based on the set reference trajectory and the detected force can be realized by the following way: According to the detected external force, a first acceleration reflecting the influence of the external force is obtained; according to the set reference trajectory, a second acceleration reflecting the influence of the tracking trajectory is obtained; based on the first acceleration, the second acceleration and an acceleration adjustment factor, a synthetic acceleration is calculated.

[0047] In the embodiment, the influence of the person's external force and the influence of the tracking trajectory are represented in the form of acceleration, respectively denoted as first acceleration and second acceleration .

[0048] The first acceleration is related to the external force as follows:

[0049] wherein, is a proportional coefficient for converting a three-dimensional force vector into a three-dimensional acceleration, represents the external force and torque of the end of the mechanical arm, is the gravity vector of the target carrying object.

[0050] The step of obtaining the second acceleration reflecting the influence of the tracking trajectory according to the set reference trajectory can be realized by the following way: A state equation of a robot end effector is constructed, an acceleration sequence at each time point is constructed based on the state equation, a corresponding state sequence is determined based on the acceleration input sequence, a cost function of motion is constructed based on a set reference trajectory and the state sequence, the acceleration sequence in the cost function is solved, and a second acceleration reflecting the influence of the tracking trajectory is obtained based on the solved acceleration sequence.

[0051] The second acceleration is established The state vector is established in connection with the reference trajectory The discrete state equation is established as follows:

[0052] wherein, is a discrete time period of the mpc, , are a zero matrix and a unit matrix respectively, A and B respectively represent coefficient matrices. It is assumed that, at a time point , an acceleration input at a future time point is prepared as: . Then, the prepared future step acceleration input sequence is:

[0053] Based on the acceleration input sequence, a corresponding state sequence can be determined as:

[0054] The relationship can be expressed as:

[0055] Based on the set reference trajectory and the state sequence, a cost function of motion is constructed as follows:

[0056] wherein, is the set reference trajectory, is a defined weight matrix, and is usually expressed in a diagonal form.

[0057] The in the above formula is brought into the cost function of motion, and a QP (quadratic programming) problem about the variable is obtained, and the final is obtained by solving the QP. The first three elements of the final are extracted, and the second acceleration reflecting the influence of the tracking trajectory is obtained.

[0058] An acceleration adjustment factor is constructed based on the external force and the adjustable parameter, and is specifically as follows:

[0059] wherein, is the adjustable parameter, is the magnitude of the external force, so that when the external force module is less than the threshold value b, λ tends to 0 (dependent on the MPC, that is, the tracking trajectory), and when the external force is greater than b, λ tends to 1 (dependent on the human force).

[0060] Finally, a synthetic acceleration is obtained based on the first acceleration, the second acceleration and the acceleration adjustment factor, and is constructed as follows:

[0061] On this basis, the desired trajectory is determined according to the synthetic acceleration.

[0062] In the human-robot collaborative control scene in the embodiment, compliant control is introduced, and the compliance of force interaction is realized through impedance control to prevent rigid force interaction.

[0063] In common robot tasks, the force and control target of the end effector of the robot are set in the Cartesian space, so compared with the traditional joint space dynamics model, the dynamics equation in the Cartesian space is more in line with the demand of the task space. For example, the control of the end position and attitude, the interaction force between the end and the environment and other task targets are naturally defined in the Cartesian space, so the dynamics equation in the Cartesian system is needed to model and control.

[0064] In the embodiment, the impedance control force is obtained based on the external force and the desired trajectory through the impedance controller, and can be realized through the following manner: According to the relationship between the joint space dynamics equation and the Cartesian space dynamics equation, a complete Cartesian space dynamics equation is obtained to construct the impedance controller under the complete Cartesian space dynamics equation; the impedance control force is calculated based on the external force and the desired trajectory through the impedance controller.

[0065] The Cartesian space dynamics equation can be expressed as follows:

[0066] In the formula, , and is the total external force (torque) in the Cartesian space, the control force (torque) and the external disturbance force (torque), which are all vectors of , including force and torque. , , Position, velocity, acceleration, including translation and rotation, at the end, a total of 6 degrees of freedom. , , Inertia matrix, Coriolis matrix and gravity matrix in Cartesian space.

[0067] The dynamics equation in Cartesian space needs to be established by the joint space dynamics equation, which is defined as:

[0068] Wherein, The control torque input by the control structure, The torque applied by the external environment, q Joint angle.

[0069] The relationship between force F and joint torque Can be established by Jacobian matrix The relationship is:

[0070] Wherein, Obtained by vector integral method, the specific process is not described in this paper.

[0071] The relationship between the Cartesian pose of the end effector and the joint angle can also be established by using the Jacobian matrix, and the velocity and acceleration in Cartesian space are respectively represented as:

[0072] The relationship between the joint space dynamics equation and the Cartesian space dynamics equation is:

[0073] By solving the above equation, we get , , So as to construct the complete Cartesian space dynamics equation, and further construct the impedance controller under the complete Cartesian space dynamics equation.

[0074] In this embodiment, the desired trajectory specifically includes the desired pose, the desired velocity and the desired acceleration, and the impedance control force is calculated based on the external force and the desired trajectory through the impedance control. Specifically, this step can be realized by the following way: According to the desired pose, the desired speed and the desired acceleration in the desired trajectory, and the obtained actual pose, the actual speed and the actual acceleration, a position difference, a speed difference and an acceleration difference are calculated; a closed loop relationship between the external force, the position difference, the speed difference, the acceleration difference and a desired matrix of impedance control in the Cartesian space is constructed through the impedance controller; and an impedance control force is calculated based on the external force satisfying the closed loop relationship and the desired trajectory.

[0075] The control target in this stage is to realize a closed loop dynamics equation in the following form:

[0076] wherein, , and respectively represent a desired inertia matrix, a damping matrix and a stiffness matrix. represents an external force suffered by the end of the mechanical arm. , , respectively represent a position difference between a desired pose and an actual pose of the end of the robot, a speed difference between a desired speed and an actual speed, and an acceleration deviation between a desired acceleration and an actual acceleration. Specifically, they can be represented as:

[0077] wherein, , , represent an actual pose, an actual speed and an actual acceleration of the end effector of the mechanical arm, , , represent a corresponding desired pose, a desired speed and a desired acceleration of the end effector of the mechanical arm.

[0078] In combination with the above-mentioned dynamics equation in the Cartesian space and the closed loop dynamics equation, a Cartesian space impedance control force shown in the following is obtained based on the external force satisfying the closed loop relationship and the desired trajectory: :

[0079] In order to ensure that the desired inertia of the system is consistent with the actual inertia and simplify the calculation of dynamics compensation, the desired inertia matrix of the impedance control in the Cartesian space can be designed to be the same as the inertia matrix of the robot, as shown in the following:

[0080] Through the above formula, the desired dynamics constructed is completely consistent with the actual dynamics of the robot, so that the entire system satisfies the physical consistency, is more likely to satisfy the energy conservation condition, thereby preventing the system from shaking due to energy injection to ensure the stability of the controller.

[0081] Combining the relationship of the force F and the joint torque , the final impedance control rate in the Cartesian system can be obtained as follows:

[0082] After determining the control normal force and the impedance control force by the above method, the control torque of the robot is calculated by combining the control normal force and the impedance control force. Specifically, this step can be implemented by the following method: Based on the impedance control force and the control normal force, a total control force is calculated; and based on the total control force and the Jacobian matrix, the control torque of the robot is calculated.

[0083] In actual operation, the impedance controller and the control normal force cannot be simply superimposed, because if the displacement along the action of is generated, the displacement will cause the force in the opposite direction to to offset the action of , which will cause the overall contact force to decrease, so it is necessary to ensure that the impedance control force is in the direction orthogonal to the control normal force . Therefore, the total control force is calculated according to the following formula:

[0084] Based on the total control force and the Jacobian matrix described above, the control torque of the robot is calculated:

[0085] By the above method, the impedance control direction and the normal contact force direction are orthogonal to each other and do not affect each other.

[0086] Thus, the control torque for realizing robot control is obtained, and robot control can be performed based on the control torque, thereby realizing human-robot collaborative carrying control. Among them, Figure 3 and Figure 4 respectively show the displacement change of the target carrying object in the carrying process and the force change curve of the target carrying object over time under the control scheme of the embodiment.

[0087] The control scheme provided in the embodiment can realize tracking of the expected trajectory while considering the influence of external force, thereby achieving the purpose of avoiding target deviation while maintaining the comfort of operation.

[0088] Based on the same inventive concept, please refer to Figure 5The embodiment of the present application further provides a functional module schematic diagram of the man-machine collaborative carrying control system, and the embodiment can divide the functional modules of the man-machine collaborative carrying control system according to the method embodiment. For example, each functional module can be divided according to each function, or two or more functions can be integrated in one processing module. The integrated module can be realized in the form of hardware or in the form of a software functional module. It should be noted that the division of the module in the embodiment of the present application is illustrative, and is only a logical function division, and another division mode can be used in actual implementation.

[0089] For example, in the case of dividing each functional module according to each function, Figure 5 The man-machine collaborative carrying control system shown is only a device schematic diagram. The man-machine collaborative carrying control system can include a first calculation module, a measurement module, a second calculation module, a third calculation module, a determination module and a calculation control module, and the functions of each functional module of the man-machine collaborative carrying control system are described in detail below.

[0090] The first calculation module is configured to calculate a desired normal force applied by the robot to the target carrying object; The measurement module is configured to measure a real-time normal force on the target carrying object through a sensor; The second calculation module is configured to calculate a control normal force that should be applied based on the desired normal force and the real-time normal force; The third calculation module is configured to calculate a resultant acceleration based on a set reference trajectory and a detected external force; The determination module is configured to determine a desired trajectory according to the resultant acceleration, and obtain an impedance control force based on the external force and the desired trajectory through an impedance controller; The calculation control module is configured to calculate the control torque of the robot in combination with the control normal force and the impedance control force.

[0091] The man-machine collaborative carrying control system provided in the embodiment can be used to execute the man-machine collaborative carrying control method in any of the embodiments described above. For details not described in the embodiment, refer to the corresponding description of the above embodiments, which will not be described herein.

[0092] Please refer to Figure 6 A structural block diagram of an electronic device is provided in the embodiment of the present application, and the electronic device can be a computer device, a server or the like in a control platform. The electronic device includes a memory, a processor and a communication module. The memory, the processor and the communication module are directly or indirectly electrically connected to each other to realize data transmission or interaction. For example, these elements can be electrically connected to each other through one or more communication buses or signal lines.

[0093] Memory is used to store computer programs or data. Memory can include, but is not limited to, random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), and electrically erasable programmable read-only memory (EEPROM).

[0094] The processor is used to read / write data or programs stored in the memory and execute the human-machine collaborative handling control method provided by any embodiment of the present invention.

[0095] The communication module is used to establish a communication connection between the electronic device and other communication terminals through the network, and is used to send and receive data through the network.

[0096] It should be understood that Figure 6 The structure shown is only a schematic diagram of the structure of the electronic device. The electronic device may also include Figure 6 More or fewer components than shown, or with Figure 6 Different configurations shown.

[0097] Furthermore, an embodiment of the present invention also provides a computer-readable storage medium, which stores machine-executable instructions. When the machine-executable instructions are executed, the human-machine collaborative transport control method provided in the above embodiment is implemented.

[0098] Specifically, the computer-readable storage medium can be a general-purpose storage medium, such as a removable disk or hard disk. When the computer program on the computer-readable storage medium is executed, the above-described human-machine collaborative transport control method can be executed. Regarding the processes involved in executing the computer-readable storage medium and its executable instructions, please refer to the relevant description of the above-described method embodiment and will not be detailed here.

[0099] In the embodiments of the present application, it should be understood that the disclosed apparatus and method can be implemented in other manners. The embodiments described above are merely exemplary, for example, the division of the units is only a logical function division, and there can be another division manner in actual implementation; for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed mutual couplings or direct couplings or communication connections can be indirect couplings or communication connections through some interfaces, devices or units, and can be in electrical, mechanical or other forms.

[0100] In addition, the units described as separate components can or can not be physically separate, and the components displayed as units can or can not be physical units, i.e., can be located in one place, or can be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purposes of the embodiments of the present application.

[0101] In addition, the various functional modules in the various embodiments of the present application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0102] It should be noted that if the functions are implemented in the form of software function modules and sold or used as independent products, they can be stored in a computer readable storage medium. Based on this understanding, the technical solutions of the present application essentially or the parts that make contributions to the prior art or parts of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), magnetic disk or optical disk, and various media that can store program codes.

[0103] In this document, the terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations.

[0104] The above merely illustrates the embodiments of the present application but should not be taken as limitations to the protection scope of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A human-machine collaborative handling control method, characterized in that: The method comprises: Calculate the expected normal force that the robot applies to the target object; obtaining a real-time normal force on the target transport object by measuring with a sensor; Calculating a control normal force that should be applied based on the desired normal force and the real-time normal force; Based on the set reference trajectory and the detected external force, the resultant acceleration is calculated; determining a desired trajectory according to the resultant acceleration, and obtaining an impedance control force based on the external force and the desired trajectory through an impedance controller; The control torque of the robot is calculated by combining the control normal force and the impedance control force.

2. The human-machine collaborative transport control method according to claim 1, characterized in that: The step of calculating the expected normal force applied by the robot to the target transport object comprises: Obtain the rotation matrix of the robot's end effector coordinate system relative to the base coordinate system; determining a direction of a normal contact force applied by the end effector to the target transport object based on the rotation matrix; Calculating the angle between the normal contact force direction and the vertical upward vector; The expected normal force is calculated based on the direction, angle, friction coefficient of the normal contact force and the gravity of the target transport object.

3. The human-machine collaborative transport control method according to claim 1, characterized in that: The step of calculating the control normal force to be applied based on the expected normal force and the real-time normal force includes: According to the expected normal force and real-time normal force at each time point, the control normal force at the next time point is calculated using the PI control method; Perform curve fitting based on the controlled normal force at each time point in the force control cycle to obtain a change curve of the controlled normal force; The control normal force to be applied at each time point is determined based on the variation curve.

4. The human-machine collaborative transport control method according to claim 1, characterized in that: The step of calculating the synthetic acceleration based on the set reference trajectory and the detected external force includes: Obtaining a first acceleration reflecting the influence of the external force according to the detected external force; According to the set reference trajectory, a second acceleration reflecting the influence of the tracking trajectory is obtained; A synthetic acceleration is calculated based on the first acceleration, the second acceleration, and the acceleration adjustment factor.

5. The human-machine collaborative transport control method according to claim 4, characterized in that: The step of obtaining a second acceleration reflecting the influence of the tracking trajectory according to the set reference trajectory includes: Constructing a state equation of the robot end effector, and constructing an acceleration sequence at each time point based on the state equation; determining a corresponding state sequence based on the acceleration input sequence; Constructing a motion cost function based on the set reference trajectory and the state sequence; The acceleration sequence in the cost function is solved, and a second acceleration reflecting the influence of the tracking trajectory is obtained based on the solved acceleration sequence.

6. The human-machine collaborative transport control method according to claim 1, characterized in that: The step of obtaining the impedance control force based on the external force and the desired trajectory by the impedance controller includes: According to the relationship between the joint space dynamic equation and the Cartesian space dynamic equation, the complete Cartesian space dynamic equation is obtained to construct an impedance controller under the complete Cartesian space dynamic equation; The impedance control force is calculated by the impedance controller based on the external force and the desired trajectory.

7. The human-machine collaborative transport control method according to claim 6, characterized in that: The desired trajectory includes a desired posture, a desired velocity, and a desired acceleration; The step of calculating the impedance control force based on the external force and the desired trajectory by the impedance controller includes: Calculating a position difference, a velocity difference, and an acceleration difference based on the desired position, the desired velocity, and the desired acceleration in the desired trajectory, and the obtained actual position, the actual velocity, and the actual acceleration; Constructing a closed-loop relationship among the external force, position difference, velocity difference, acceleration difference, and an expected matrix of impedance control in Cartesian space through the impedance controller; Based on the external force satisfying the closed-loop relationship and the desired trajectory, an impedance control force is calculated.

8. The human-machine collaborative transport control method according to claim 1, characterized in that: The step of calculating the control torque of the robot by combining the control normal force and the impedance control force includes: Calculating a total control force based on the impedance control force and the control normal force; The control torque of the robot is calculated based on the total control force and the Jacobian matrix.

9. A human-machine collaborative handling control system, characterized in that: The system comprises: A first calculation module is used to calculate the expected normal force applied by the robot to the target transport object; A measurement module, configured to obtain a real-time normal force on the target transport object by measuring the normal force through a sensor; a second calculation module, configured to calculate a control normal force to be applied based on the expected normal force and the real-time normal force; A third calculation module is used to calculate the synthetic acceleration based on the set reference trajectory and the detected external force; a determination module, configured to determine a desired trajectory according to the resultant acceleration, and obtain an impedance control force based on the external force and the desired trajectory through an impedance controller; A calculation control module is used to calculate the control torque of the robot by combining the control normal force and the impedance control force.

10. An electronic device, characterized in that: The electronic device comprises one or more storage media and one or more processors communicating with the storage media, wherein the one or more storage media store machine-executable instructions executable by the processors. When the electronic device is running, the processor executes the machine-executable instructions to perform the method described in any one of claims 1 to 8.

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