Gait cooperative control method applied to lower limb prosthesis test
By adopting a collaborative gait control method on the lower limb prosthesis test platform, using vertical and rotary motion to simulate different motion states, the problems of insufficient gait simulation and unrepeatable results in the prior art are solved, and the accuracy and reliability of the lower limb prosthesis are achieved. Obtain experimental data.
Patent Information
- Application Number
- CN202411314560.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-20
- Publication Date
- 2025-01-07
AI Technical Summary
The existing human lower limb prosthetic test platform is difficult to achieve gait simulation of different movement states, and cannot effectively reveal the connection between the mechanical characteristics of the prosthetic limb and the user experience, and the test results are highly variable and non-repeatable.
A gait collaborative control method is adopted, including upper computer, upper servo electric cylinder, upper driver, S-type tension sensor, rotary plate, lower servo electric cylinder and photoelectric rotary encoder, through simulated gravity loading and navigation in the vertical direction Rotating movement in the shape of the plane achieves high-precision control of the prosthetic foot, simulating people with different heights and weights and movement processes, and providing accurate gait simulation.
The accurate simulation of the full gait of human lower limb movement is achieved, and accurate and reliable experimental data is provided for the development and performance testing of lower limb prosthetics, overcoming the problems of insufficient gait simulation and unrepeatable results in the prior art.
Smart Images
Figure CN119257806A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of lower limb prosthesis testing, and in particular to a gait coordination control method applied to lower limb prosthesis testing. Background Art
[0002] Traditional lower limb prosthesis design relies on experiments and empirical iterations. The most common method for evaluating prosthetic performance is subject testing, which involves subjective factors of the subjects, has high variability between subjects, and the test results are not repeatable.
[0003] In order to obtain more objective and repeatable test data to guide the design and parameter optimization of lower limb prostheses, human lower limb prosthesis test platforms are often used for testing.
[0004] However, most of the existing human lower limb prosthesis test platforms are used to measure specific mechanical properties. The research on a single mechanical property can hardly reveal the connection between the mechanical characteristics of the lower limb prosthesis and the user experience, and it is difficult to achieve gait simulation in different motion states. Summary of the invention
[0005] The purpose of the present invention is to overcome the deficiency of the prior art lower limb prosthesis test platform that it is difficult to achieve gait simulation in different motion states, and to provide a gait coordination control method applied to lower limb prosthesis testing.
[0006] In order to achieve the above object, the present invention adopts the following technical solutions:
[0007] A gait coordination control method applied to lower limb prosthesis test, comprising a host computer, an upper servo electric cylinder, an upper driver, an S-shaped tension and compression sensor arranged between a telescopic rod of the upper servo electric cylinder and a test prosthesis, a rotating plate in contact with the lower surface of the test prosthesis, a lower servo electric cylinder for driving the rotating plate to rotate, a photoelectric rotary encoder installed on the rotating plate, and a lower driver; the host computer is electrically connected to the upper driver and the lower driver respectively, the upper driver is electrically connected to the S-shaped tension and compression sensor and the upper servo electric cylinder respectively, and the lower driver is electrically connected to the lower servo electric cylinder and the photoelectric rotary encoder respectively;
[0008] The upper servo electric cylinder and the S-type tension and compression sensor jointly realize the simulated gravity loading and measurement in the vertical direction. The S-type tension and compression sensor is used to measure the simulated gravity applied to the test subject's artificial foot.
[0009] The rotating plate, the lower servo electric cylinder and the photoelectric rotary encoder jointly realize the loading of the rotational motion in the vertical plane (sagittal plane), and the photoelectric rotary encoder can measure the rotation angle of the rotating plate.
[0010] The steps include:
[0011] Step 1: The staff inputs the loading control curve into the upper computer, and the upper computer decomposes the loading control curve into a simulated support reaction force control curve and a swing control curve; the upper computer sends the simulated support reaction force control curve to the upper driver, and sends the swing control curve to the lower driver;
[0012] Step 2,
[0013] The upper driver performs time division on the simulated support reaction force control curve, divides the simulated support reaction force control curve into n loading cycles, and calculates the coordinate value of each division point using the simulated support reaction force control curve fitting formula;
[0014] The lower driver performs time division on the swing control curve, divides the swing control curve into n loading cycles, and calculates the coordinate value of each division point using the swing control curve fitting formula;
[0015] Step 3, set the initial value of i to 1, the upper driver sets the speed of the permanent magnet synchronous motor of the upper servo electric cylinder to 0, and the lower driver sets the speed of the permanent magnet synchronous motor of the lower servo electric cylinder to 0;
[0016] Step 3-1, the upper driver sends the i-th loading cycle of the simulated support reaction force control curve to the upper servo electric cylinder, and at the same time, the lower driver sends the i-th loading cycle of the swing control curve to the lower servo electric cylinder;
[0017] Step 4, drive time synchronization:
[0018] The upper drive and the lower drive perform round-trip timing synchronization;
[0019] Step 5, collaborative loading:
[0020] Step 5-1,
[0021] The upper driver calculates the average speed of the motor in the loading cycle according to the starting point coordinate value, the end point coordinate value and the time length of the loading cycle of the ith loading cycle of the simulated support reaction force control curve, and controls the permanent magnet synchronous motor of the upper servo electric cylinder using the average speed of the motor;
[0022] At the same time, the lower driver calculates the average speed of the motor in this loading cycle according to the starting point coordinate value, the end point coordinate value and the time length of the loading cycle of the ith loading cycle of the swing control curve, and uses the average speed of the motor to control the permanent magnet synchronous motor of the lower servo electric cylinder;
[0023] Step 5-2, the photoelectric rotary encoder monitors the rotation angle of the rotating plate and feeds the rotation angle back to the lower driver to complete the position closed-loop control;
[0024] The S-type tension and compression sensor measures the simulated support reaction force loading value, and feeds the simulated support reaction force loading value back to the upper driver to complete the closed-loop control of the loading force;
[0025] Step 5-3, the lower driver determines whether the rotation angle of the rotating plate reaches the end point of the loading curve of this loading cycle. If it has reached the end point, the swing loading control of this loading cycle ends, and the signal of the end of the swing loading control of this loading cycle is transmitted to the upper computer, and the upper computer transmits the signal of the end of the swing loading control of this loading cycle to the upper driver;
[0026] Step 5-4, the upper driver determines whether the simulated support reaction force control curve of this loading cycle has reached the end point. If it has reached the end point, the simulated support reaction force loading control of this loading cycle ends;
[0027] Step 6: When the swing loading control and simulated support reaction force loading control of this loading cycle have ended, if i<n, the host computer increases the value of i by 1 and returns to step 3-1; otherwise, all loading is ended.
[0028] The present invention can monitor the state of the artificial foot in real time. The host computer is used to set the test mode and parameters. The upper driver and the lower driver control the upper servo electric cylinder and the lower servo electric cylinder respectively through force closed-loop control and position closed-loop control to achieve high-precision transmission positioning; the S-type tension and compression sensor measures the size of the simulated gravity applied to the artificial foot of the test subject and feeds back to the upper driver to achieve force closed-loop control; the photoelectric rotary encoder measures the rotation angle of the rotating platform plate and feeds back to the lower driver to achieve position closed-loop control.
[0029] The present invention can simulate people of different heights and weights and different motion processes by controlling the vertical and rotational coordinated motion and loading of the prosthetic test bench, and can accurately simulate the full gait of human lower limb motion, thus providing accurate and reliable test data for the development and performance testing of lower limb prostheses.
[0030] Preferably, the upper driver and the lower driver both include an IPM chip, a bus voltage detection chip, a first A / D conversion chip, an isolation drive chip, a current detection chip, a second A / D conversion chip, a SOC chip integrating FPGA and ARM processor, a first RS422 interface, a second RS422 interface and an ETH interface; the IPM chip is electrically connected to the bus voltage detection chip and the isolation drive chip respectively, the isolation drive chip is electrically connected to the FPGA, the bus voltage detection chip is electrically connected to the FPGA through the first A / D conversion chip, the current detection chip is electrically connected to the three-phase line, the current detection chip is electrically connected to the FPGA through the second A / D conversion chip, the FPGA is electrically connected to the ARM processor, the FPGA is electrically connected to the host computer through the first RS422 interface, the ARM processor is electrically connected to the host computer through the second RS422 interface and the ETH interface, the IPM chip of the upper driver is connected to the permanent magnet synchronous motor of the upper servo electric cylinder through the three-phase line, and the motor encoder of the permanent magnet synchronous motor is connected to the rotating shaft of the permanent magnet synchronous motor.
[0031] The IPM chip is an intelligent power module, which mainly realizes the power inverter function; the fault signal is the status identification signal output by the IPM chip. When the IPM chip fails, it will stop working and output the fault identification signal to protect the permanent magnet synchronous motor; the FPGA sends a control signal to the IPM chip through the isolation driver chip to control the UVW three-phase voltage to drive the permanent magnet synchronous motor to rotate; the first A / D conversion chip collects the bus voltage of the IPM chip and uploads it to the FPGA to realize the working status monitoring function of the IPM chip; the second A / D conversion chip collects the UVW three-phase current and uploads it to the FPGA to realize the current closed-loop control; the motor encoder realizes the detection function of the rotation angle of the permanent magnet synchronous motor; the first RS422 interface mounted on the FPGA outputs the synchronization signal and uploads it to the host computer to realize the synchronous control of different loads; the second RS422 interface and ETH interface mounted on the ARM processor respectively realize the serial port communication and network port communication functions of the corresponding driver and the host computer. The AXI bus realizes high-bandwidth and low-latency data interaction between the FPGA and the ARM processor.
[0032] As a preference, the upper driver performs time division on the simulated support reaction force control curve by replacing it with the following steps:
[0033] The ARM processor of the upper drive performs time division on the simulated support reaction force control curve according to unit time;
[0034] The time division of the swing control curve by the lower drive is replaced by the following steps:
[0035] The ARM processor of the lower drive performs time division of the swing control curve according to the unit time.
[0036] The present invention adopts a time division interpolation algorithm to improve the fitting accuracy of the motion trajectory. The principle of the time division interpolation algorithm is: the motion trajectory to be interpolated is divided into a number of small segments, each small segment corresponds to a unit time interval, and within each unit time interval, the control speed of the motor within the time interval is calculated according to the starting point coordinates and the end point coordinates of the motion trajectory.
[0037] Preferably, step 4 includes the following specific steps:
[0038] The lower driver sends an inquiry message to the upper computer at the start of its calibration time slot, and the upper computer forwards the inquiry message to the upper driver;
[0039] The upper driver measures the arrival time of the inquiry message signal and sends a response signal to the host computer at the beginning of its timing slot, and the host computer forwards the response signal to the lower driver;
[0040] The lower driver measures the arrival time of the response message signal, calculates the time deviation between the local time of the lower driver and the local time of the upper driver, and uses the time deviation to compensate its own local time to complete time synchronization, and reports the completion of time synchronization signals to the upper computer and ARM processor respectively.
[0041] The present invention utilizes the bidirectional transmission of the lower driver and the upper driver to cancel the error of the signal in the channel transmission, calculates the accurate time deviation, and the lower driver compensates for the time difference to achieve time synchronization between the lower driver and the upper driver.
[0042] As a preference,
[0043] Before step 1, the following power-on self-test steps are also included:
[0044] When the FPGA program is loaded, the FPGA reports the completion of program loading to the ARM processor through the AXI bus; if the ARM processor does not receive the program loading completion signal after running for 30 seconds, the ARM processor determines that the FPGA program is not loaded normally;
[0045] FPGA detects whether the fault signal output by the IPM chip is high. If the fault signal is high, it indicates that the IPM chip is faulty. FPGA reports the IPM chip fault to the ARM processor through the AXI bus; otherwise, it reports that the IPM chip is normal.
[0046] The FPGA collects the bus voltage of the IPM chip through the first A / D conversion chip. If the bus voltage measurement value is within the range of ±10% of the set value, it reports to the ARM processor through the AXI bus that the bus voltage is normal; otherwise, it reports that the bus voltage is abnormal;
[0047] After receiving the signal that the FPGA program is loaded, the IPM chip is normal, and the bus voltage is normal, the ARM processor reports that the self-test has passed to the host computer through the second RS422 interface; otherwise, it reports that the self-test is abnormal and reports the abnormal item.
[0048] Preferably, the horizontal coordinate of the loading control curve is the rotation angle of the rotating plate, and the vertical coordinate is the simulated ground support reaction force; the horizontal coordinate of the simulated support reaction force control curve is time, and the vertical coordinate is the simulated ground support reaction force; the horizontal coordinate of the swing control curve is time, and the vertical coordinate is the swing angle of the rotating platform.
[0049] Preferably, it also includes a frame, an upper bracket and a lower bracket arranged on the frame; the lower bracket is located at the lower right of the upper bracket, and the upper servo electric cylinder is located at the upper left of the upper bracket; the rotating plate is rotatably connected to the upper bracket through an upper rotating shaft, and the lower servo electric cylinder is rotatably connected to the lower bracket through a lower rotating shaft, the lower rotating shaft is located on the axis line of the telescopic rod of the lower servo electric cylinder, the upper end of the telescopic rod of the lower servo electric cylinder is connected to the right part of the lower surface of the rotating plate through a hinge, and the photoelectric rotary encoder is rotatably connected to the upper rotating shaft.
[0050] Therefore, the present invention has the following beneficial effects: it can realize the coordinated control of different motion modes and can realize the accurate simulation of different motion gaits of the lower limbs of the human body. BRIEF DESCRIPTION OF THE DRAWINGS
[0051] Figure 1 It is a structural schematic diagram of the present invention;
[0052] Figure 2 It is a principle block diagram of the present invention;
[0053] Figure 3 It is a principle block diagram of the connection between the upper driver of the present invention and the permanent magnet synchronous motor of the upper servo electric cylinder;
[0054] Figure 4 It is a schematic diagram of a round-trip timing synchronization algorithm according to an embodiment of the present invention. DETAILED DESCRIPTION
[0055] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.
[0056] like Figure 1-Figure 2The embodiment shown is a gait coordination control method applied to lower limb prosthesis testing, comprising a host computer 9, an upper servo electric cylinder 1, an upper driver 2, an S-shaped tension and compression sensor 4 arranged between a telescopic rod of the upper servo electric cylinder and a test prosthesis 3, a rotating plate 5 in contact with the lower surface of the test prosthesis 3, a lower servo electric cylinder 6 for driving the rotating plate to rotate, a photoelectric rotary encoder 7 installed on the rotating plate, and a lower driver 8; the host computer is electrically connected to the upper driver and the lower driver respectively, the upper driver is electrically connected to the S-shaped tension and compression sensor and the upper servo electric cylinder respectively, and the lower servo electric cylinder is electrically connected to the S-shaped tension and compression sensor and the upper servo electric cylinder respectively. The upper and lower drivers are electrically connected to the lower servo electric cylinder and the photoelectric rotary encoder respectively; it also includes a frame, an upper bracket 10 and a lower bracket 20 arranged on the frame; the lower bracket is located at the lower right of the upper bracket, and the upper servo electric cylinder is located at the upper left of the upper bracket; the rotating plate is rotatably connected to the upper bracket through an upper rotating shaft, and the lower servo electric cylinder is rotatably connected to the lower bracket through a lower rotating shaft, the lower rotating shaft is located on the axis line of the telescopic rod of the lower servo electric cylinder, the upper end of the telescopic rod of the lower servo electric cylinder is connected to the right part of the lower surface of the rotating plate through a hinge 71, and the photoelectric rotary encoder is rotatably connected to the upper rotating shaft.
[0057] like Figure 3 As shown, the upper driver includes an IPM chip, a bus voltage detection chip, a first A / D conversion chip, an isolation drive chip, a current detection chip, a second A / D conversion chip, a SOC chip integrating FPGA and ARM processors, a first RS422 interface, a second RS422 interface and an ETH interface; the IPM chip is electrically connected to the bus voltage detection chip and the isolation drive chip respectively, the isolation drive chip is electrically connected to the FPGA, the bus voltage detection chip is electrically connected to the FPGA through the first A / D conversion chip, the current detection chip is electrically connected to the three-phase line, the current detection chip is electrically connected to the FPGA through the second A / D conversion chip, the FPGA is electrically connected to the ARM processor, the FPGA is electrically connected to the host computer through the first RS422 interface, the ARM processor is electrically connected to the host computer through the second RS422 interface and the ETH interface, the IPM chip of the upper driver is connected to the permanent magnet synchronous motor of the upper servo electric cylinder through the three-phase line, and the motor encoder of the permanent magnet synchronous motor is connected to the rotating shaft of the permanent magnet synchronous motor.
[0058] Figure 3 The rectifier bridge in the chip is responsible for converting AC power into DC power, the DC / DC chip realizes the DC step-down function, and the digital power supply chip is responsible for providing the various DC powers required by the chip.
[0059] The structure of the lower driver is the same as that of the upper driver. The FPGA of the lower driver is electrically connected to the upper computer through the RS422 interface, and the ARM processor of the lower driver is electrically connected to the upper computer through the second RS422 interface and the ETH interface; the IPM chip of the lower driver is connected to the permanent magnet synchronous motor of the lower servo electric cylinder through a three-phase line, and the motor encoder of the lower permanent magnet synchronous motor is connected to the rotating shaft of the permanent magnet synchronous motor.
[0060] The steps include:
[0061] Power-on self-test:
[0062] When the FPGA program is loaded, the FPGA reports the completion of program loading to the ARM processor through the AXI bus; if the ARM processor does not receive the program loading completion signal after running for 30 seconds, the ARM processor determines that the FPGA program is not loaded normally;
[0063] FPGA detects whether the fault signal output by the IPM chip is high. If the fault signal is high, it indicates that the IPM chip is faulty. FPGA reports the IPM chip fault to the ARM processor through the AXI bus; otherwise, it reports that the IPM chip is normal.
[0064] The FPGA collects the bus voltage of the IPM chip through the first A / D conversion chip. If the bus voltage measurement value is within the range of ±10% of the set value, it reports to the ARM processor through the AXI bus that the bus voltage is normal; otherwise, it reports that the bus voltage is abnormal;
[0065] After receiving the signal that the FPGA program is loaded, the IPM chip is normal, and the bus voltage is normal, the ARM processor reports that the self-test has passed to the host computer through the second RS422 interface; otherwise, it reports that the self-test is abnormal and reports the abnormal item.
[0066] Step 1: The staff inputs the loading control curve into the upper computer, and the upper computer decomposes the loading control curve into a simulated support reaction force control curve and a swing control curve; the upper computer sends the simulated support reaction force control curve to the upper driver, and sends the swing control curve to the lower driver;
[0067] The horizontal coordinate of the loading control curve is the rotation angle of the rotating plate, and the vertical coordinate is the simulated ground support reaction force; the horizontal coordinate of the simulated support reaction force control curve is time, and the vertical coordinate is the simulated ground support reaction force; the horizontal coordinate of the swing control curve is time, and the vertical coordinate is the swing angle of the rotating platform.
[0068] Step 2, the ARM processor of the upper driver performs time division on the simulated support reaction force control curve according to the unit time, divides the simulated support reaction force control curve into n loading cycles, and calculates the coordinate value of each division point using the simulated support reaction force control curve fitting formula;
[0069] The ARM processor of the lower driver performs time division on the swing control curve according to the unit time, divides the swing control curve into n loading cycles, and calculates the coordinate value of each division point by using the swing control curve fitting formula;
[0070] Step 3,
[0071] Assume that the initial value of i is 1, the upper driver sets the speed of the permanent magnet synchronous motor of the upper servo electric cylinder to 0, and the lower driver sets the speed of the permanent magnet synchronous motor of the lower servo electric cylinder to 0;
[0072] Step 3-1, the upper driver sends the i-th loading cycle of the simulated support reaction force control curve to the upper servo electric cylinder, and at the same time, the lower driver sends the i-th loading cycle of the swing control curve to the lower servo electric cylinder;
[0073] Step 4, drive time synchronization:
[0074] The upper drive and the lower drive perform round-trip timing synchronization;
[0075] like Figure 4 As shown, the lower driver sends an inquiry message to the upper computer at the start of its time slot, and the upper computer forwards the inquiry message to the upper driver;
[0076] The upper driver measures the arrival time of the inquiry message signal and sends a response signal to the host computer at the beginning of its timing slot, and the host computer forwards the response signal to the lower driver;
[0077] The lower drive measures the arrival time of the reply message signal and calculates the time deviation between the local time of the lower drive and the local time of the upper drive:
[0078] Figure 4 In the figure, T is the timing period of the upper and lower drivers, t e is the local time error between the upper and lower drivers; t s is the transmission delay of the timing signal; t1 is the arrival time of the inquiry message recorded by the upper driver; t2 is the arrival time of the response signal recorded by the lower driver, Figure 4 We can get:
[0079] t1=t s +t e
[0080] t2+t e =T+t s
[0081] From the above two formulas, we can get:
[0082] te =(t1+T-t2) / 2, we get t e Afterwards, the lower driver compensates its own local time so that the upper driver and the lower driver complete time synchronization, and reports a signal of time synchronization completion to the upper computer and the ARM processor through the first RS422 interface and the AXI bus interface respectively.
[0083] Step 5, collaborative loading:
[0084] Step 5-1,
[0085] The upper driver calculates the average speed of the motor in the loading cycle according to the starting point coordinate value, the end point coordinate value and the time length of the loading cycle of the ith loading cycle of the simulated support reaction force control curve, and controls the permanent magnet synchronous motor of the upper servo electric cylinder using the average speed of the motor;
[0086] At the same time, the lower driver calculates the average speed of the motor in this loading cycle according to the starting point coordinate value, the end point coordinate value and the time length of the loading cycle of the ith loading cycle of the swing control curve, and uses the average speed of the motor to control the permanent magnet synchronous motor of the lower servo electric cylinder;
[0087] Step 5-2, the photoelectric rotary encoder monitors the rotation angle of the rotating plate and feeds the rotation angle back to the lower driver to complete the position closed-loop control;
[0088] The S-type tension and compression sensor measures the simulated support reaction force loading value, and feeds the simulated support reaction force loading value back to the upper driver to complete the closed-loop control of the loading force;
[0089] Step 5-3, the lower driver determines whether the rotation angle of the rotating plate reaches the end point of the loading curve of this loading cycle. If it has reached the end point, the swing loading control of this loading cycle ends, and the signal of the end of the swing loading control of this loading cycle is transmitted to the upper computer, and the upper computer transmits the signal of the end of the swing loading control of this loading cycle to the upper driver;
[0090] Step 5-4, the upper driver determines whether the simulated support reaction force control curve of this loading cycle has reached the end point. If it has reached the end point, the simulated support reaction force loading control of this loading cycle ends;
[0091] Step 6: When the swing loading control and simulated support reaction force loading control of this loading cycle have ended, if i<n, the host computer increases the value of i by 1 and returns to step 3-1; otherwise, all loading is ended.
[0092] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims
1. A gait coordination control method for lower limb prosthesis testing, characterized in that: The invention comprises an upper computer (9), an upper servo electric cylinder (1), an upper driver (2), an S-shaped tension and compression sensor (4) arranged between a telescopic rod of the upper servo electric cylinder and a test artificial foot (3), a rotating plate (5) in contact with the lower surface of the test artificial foot, a lower servo electric cylinder (6) for driving the rotating plate to rotate, a photoelectric rotary encoder (7) and a lower driver (8) installed on the rotating plate; the upper computer is electrically connected to the upper driver and the lower driver respectively, the upper driver is electrically connected to the S-shaped tension and compression sensor and the upper servo electric cylinder respectively, and the lower driver is electrically connected to the lower servo electric cylinder and the photoelectric rotary encoder respectively; and the following steps are included: Step 1: The staff inputs the loading control curve into the upper computer, and the upper computer decomposes the loading control curve into a simulated support reaction force control curve and a swing control curve; the upper computer sends the simulated support reaction force control curve to the upper driver, and sends the swing control curve to the lower driver; Step 2, The upper driver performs time division on the simulated support reaction force control curve, divides the simulated support reaction force control curve into n loading cycles, and calculates the coordinate value of each division point using the simulated support reaction force control curve fitting formula; The lower driver performs time division on the swing control curve, divides the swing control curve into n loading cycles, and calculates the coordinate value of each division point using the swing control curve fitting formula; Step 3, set the initial value of i to 1, the upper driver sets the speed of the permanent magnet synchronous motor of the upper servo electric cylinder to 0, and the lower driver sets the speed of the permanent magnet synchronous motor of the lower servo electric cylinder to 0; Step 3-1, the upper driver sends the i-th loading cycle of the simulated support reaction force control curve to the upper servo electric cylinder, and at the same time, the lower driver sends the i-th loading cycle of the swing control curve to the lower servo electric cylinder; Step 4, drive time synchronization: The upper drive and the lower drive perform round-trip timing synchronization; Step 5, collaborative loading: Step 5-1, The upper driver calculates the average speed of the motor in the loading cycle according to the starting point coordinate value, the end point coordinate value and the time length of the loading cycle of the ith loading cycle of the simulated support reaction force control curve, and controls the permanent magnet synchronous motor of the upper servo electric cylinder using the average speed of the motor; At the same time, the lower driver calculates the average speed of the motor in this loading cycle according to the starting point coordinate value, the end point coordinate value and the time length of the loading cycle of the ith loading cycle of the swing control curve, and uses the average speed of the motor to control the permanent magnet synchronous motor of the lower servo electric cylinder; Step 5-2, the photoelectric rotary encoder monitors the rotation angle of the rotating plate and feeds the rotation angle back to the lower driver to complete the position closed-loop control; The S-type tension and compression sensor measures the simulated support reaction force loading value, and feeds the simulated support reaction force loading value back to the upper driver to complete the closed-loop control of the loading force; Step 5-3, the lower driver determines whether the rotation angle of the rotating plate reaches the end point of the loading curve of this loading cycle. If it has reached the end point, the swing loading control of this loading cycle ends, and the signal of the end of the swing loading control of this loading cycle is transmitted to the upper computer, and the upper computer transmits the signal of the end of the swing loading control of this loading cycle to the upper driver; Step 5-4, the upper driver determines whether the simulated support reaction force control curve of this loading cycle has reached the end point. If it has reached the end point, the simulated support reaction force loading control of this loading cycle is terminated; Step 6, when the swing loading control and the simulated support reaction force loading control of this loading cycle have both ended, if i<n, the upper computer increases the i value by 1 and returns to step 3-1; otherwise, all loading is terminated.
2. The gait coordination control method for lower limb prosthesis testing according to claim 1 is characterized in that: The upper driver and the lower driver both include an IPM chip, a bus voltage detection chip, a first A / D conversion chip, an isolation drive chip, a current detection chip, a second A / D conversion chip, a SOC chip integrating an FPGA and an ARM processor, a first RS422 interface, a second RS422 interface and an ETH interface; the IPM chip is electrically connected to the bus voltage detection chip and the isolation drive chip respectively, the isolation drive chip is electrically connected to the FPGA, the bus voltage detection chip is electrically connected to the FPGA through the first A / D conversion chip, the current detection chip is electrically connected to the three-phase line, the current detection chip is electrically connected to the FPGA through the second A / D conversion chip, the FPGA is electrically connected to the ARM processor, the FPGA is electrically connected to the host computer through the first RS422 interface, the ARM processor is electrically connected to the host computer through the second RS422 interface and the ETH interface, the IPM chip of the upper driver is connected to the permanent magnet synchronous motor of the upper servo electric cylinder through the three-phase line, and the motor encoder of the permanent magnet synchronous motor is connected to the rotating shaft of the permanent magnet synchronous motor.
3. The gait coordination control method for lower limb prosthesis testing according to claim 2 is characterized in that: The time division of the simulated support reaction force control curve by the upper drive is replaced by the following steps: The ARM processor of the upper drive performs time division on the simulated support reaction force control curve according to unit time; The time division of the swing control curve by the lower drive is replaced by the following steps: The ARM processor of the lower drive performs time division of the swing control curve according to the unit time.
4. The gait coordination control method for lower limb prosthesis testing according to claim 1, characterized in that: Step 4 includes the following specific steps: The lower driver sends an inquiry message to the upper computer at the start of its calibration time slot, and the upper computer forwards the inquiry message to the upper driver; The upper driver measures the arrival time of the inquiry message signal and sends a response signal to the host computer at the beginning of its timing slot, and the host computer forwards the response signal to the lower driver; The lower driver measures the arrival time of the response message signal, calculates the time deviation between the local time of the lower driver and the local time of the upper driver, and uses the time deviation to compensate its own local time to complete time synchronization, and reports the completion of time synchronization signals to the upper computer and ARM processor respectively.
5. The gait coordination control method for lower limb prosthesis testing according to claim 2, characterized in that: Before step 1, the following power-on self-test steps are also included: When the FPGA program is loaded, the FPGA reports the completion of program loading to the ARM processor through the AXI bus; if the ARM processor does not receive the program loading completion signal after running for 30 seconds, the ARM processor determines that the FPGA program is not loaded normally; FPGA detects whether the fault signal output by the IPM chip is high. If the fault signal is high, it indicates that the IPM chip is faulty. FPGA reports the IPM chip fault to the ARM processor through the AXI bus; otherwise, it reports that the IPM chip is normal. The FPGA collects the bus voltage of the IPM chip through the first A / D conversion chip. If the bus voltage measurement value is within the range of ±10% of the set value, it reports to the ARM processor through the AXI bus that the bus voltage is normal; otherwise, it reports that the bus voltage is abnormal; After receiving the signal that the FPGA program is loaded, the IPM chip is normal, and the bus voltage is normal, the ARM processor reports that the self-test has passed to the host computer through the second RS422 interface; otherwise, it reports that the self-test is abnormal and reports the abnormal item.
6. The gait coordination control method for lower limb prosthesis testing according to claim 1, characterized in that: The horizontal coordinate of the loading control curve is the rotation angle of the rotating plate, and the vertical coordinate is the simulated ground support reaction force; the horizontal coordinate of the simulated support reaction force control curve is time, and the vertical coordinate is the simulated ground support reaction force; the horizontal coordinate of the swing control curve is time, and the vertical coordinate is the swing angle of the rotating platform.
7. The gait coordination control method for lower limb prosthesis testing according to claim 1 or 2 or 3 or 4 or 5 or 6, characterized in that: The device also includes a frame, an upper frame (10) and a lower frame (20) arranged on the frame; the lower frame is located at the lower right side of the upper frame, and the upper servo electric cylinder is located at the upper left side of the upper frame; the rotating plate is rotatably connected to the upper frame via an upper rotating shaft, and the lower servo electric cylinder is rotatably connected to the lower frame via a lower rotating shaft, the lower rotating shaft is located on the axis center line of the telescopic rod of the lower servo electric cylinder, the upper end of the telescopic rod of the lower servo electric cylinder is connected to the right part of the lower surface of the rotating plate via a hinge (71), and the photoelectric rotary encoder is rotatably connected to the upper rotating shaft.