A distributed modular human-computer interaction force measurement system

Abstract

A distributed modular human-computer interaction force measurement system, comprising a rigid expansion structure, a sensing panel module, an isolation guide rail, a flexible capacitive sensor assembly, and a data processing and analysis system; a plurality of threaded holes are arranged inside the rigid expansion structure for fixing the isolation guide rail, and at the same time, a plurality of channels are evenly arranged inside for installing the sensing panel module; a cavity is arranged at the channel of the rigid expansion structure for accommodating the flexible capacitive sensor assembly; the sensing panel module is integrally in a mushroom shape, with a curved surface structure at the upper part and a cylindrical structure at the lower part, and the cylindrical structure is in clearance fit with the channel on the rigid expansion structure, and the end of the cylindrical structure is always in contact with the flexible capacitive sensor; the fixed isolation guide rail is fixedly arranged in parallel inside the rigid expansion structure for limiting the sensing panel module; the flexible capacitive sensor assembly is connected to the data processing and analysis system for acquiring and processing the interaction force measurement data.

Description

Technical Field

[0001] The present invention relates to a distributed modular human - machine interaction force measurement system, belonging to the fields of intelligent robots, wearable equipment technology, and human - machine ergonomics evaluation. Background Art

[0002] As a wearable robot, the exoskeleton can enhance human functions while providing functions such as protection and support for the wearer, and assist the wearer to complete operation tasks, having broad application prospects in the fields of military, industry, medical treatment, fire protection, etc. In terms of the wearing method, flexible straps are mainly used to connect the exoskeleton and the human body, and auxiliary forces or torques are applied to the human body through rigid binding structures. Poor human - machine interaction forces will lead to low assistance efficiency and cause harm to the wearer. Therefore, the detection of the interaction force between the exoskeleton and the human body is the key to the design of the exoskeleton bionic mechanism, the research of control strategies, and human - machine ergonomics evaluation.

[0003] Chinese Patent CN111714324A, "Human - Machine Interaction Force Acquisition System", measures the human - machine interaction force by installing inflatable airbags on the exoskeleton. However, due to the strong "non - linear" flexible characteristics of human skin and muscles, the collected data has a large error, and the measurement process has a certain degree of instability. Chinese Patent CN109470502A, "An Exoskeleton Comfort Evaluation Device and Evaluation Method Based on Multi - Sensors", measures the human - machine interaction force by sewing pressure sensors on the side of the strap close to the human body. Although it can be well fixed between the human and the machine, adding non - rigid straps to the interaction interface will instead reduce the measurement accuracy. Chinese Patent CN105643609B, "A Human - Machine Interaction Force Detection Device", provides an acquisition device based on a magnetic encoder, which can solve the problem of poor stability to a certain extent, but its mechanism is complex, has a certain interference with the movement of the exoskeleton and the human body itself, and at the same time cannot solve the problem of individual differences among different wearers. Other solutions, such as installing torque sensors or six - dimensional force sensors at the joints of the exoskeleton to measure the human - machine interaction force, all require an accurate human - machine system dynamics model as the basis, and can only perform single - point measurement, unable to obtain the interaction force distribution of the human - machine interface; using photoelectric sensors to collect the human - machine interaction force, although it has high accuracy and repeatability, this solution is costly and not suitable for low - cost prototype design. Summary of the Invention

[0004] The technical problem to be solved by the present invention is: to overcome the deficiencies of the prior art and solve the problems of poor stability, low accuracy, high cost, low versatility, and difficulty in adapting to individual differences in the human - machine interaction force measurement scheme.

[0005] The object of the present invention is achieved through the following technical solutions:

[0006] A distributed modular human-computer interaction force measurement system, comprising a rigid expansion structure, a sensing panel module, an isolation guide rail, a flexible capacitance sensor assembly, and a data processing and analysis system;

[0007] The rigid expansion structure has the same geometric dimensions as the binding structure of the exoskeleton to be measured; several threaded holes are provided on the inner side of the rigid expansion structure for fixing the isolation guide rail, and several channels are evenly arranged on the inner side for installing the sensing panel module; a cavity is provided at the channel of the rigid expansion structure for accommodating the flexible capacitance sensor assembly;

[0008] The sensing panel module has an overall mushroom-like structure, with a curved surface structure on the upper part and a cylindrical structure on the lower part. The cylindrical structure is in clearance fit with the channel on the rigid expansion structure, and the end of the cylindrical structure is always in contact with the flexible capacitance sensor;

[0009] The fixed isolation guide rail is fixedly arranged parallel to the inner side of the rigid expansion structure to prevent the sensing panel module from falling and restrict its rotation around its own axis;

[0010] The flexible capacitance sensor assembly is connected to the data processing and analysis system for acquiring and processing the interactive force measurement data.

[0011] Preferably, the channel of the rigid expansion structure is circular, and the lower part of the sensing panel module is a cylindrical structure.

[0012] Preferably, the diameter of the lower cylinder of the sensing panel module is consistent with the acquisition range of the flexible capacitance sensor assembly.

[0013] Preferably, the sensing panel modules are installed on the rigid expansion structure in an array form.

[0014] Preferably, the flexible capacitance sensor assembly includes a flexible capacitance sensor body and an acquisition circuit. The acquisition circuit includes an STM32L433 chip and a PCap01 capacitance acquisition chip, which are jointly used to complete the data acquisition of the flexible capacitance sensor body and send the acquired capacitance data to the data processing and analysis system after packaging.

[0015] Preferably, after receiving the measurement data, the data processing and analysis system converts the capacitance data into pressure data according to the capacitance-pressure curve function, which is obtained by fitting through a calibration experiment, and finally stores the processed data.

[0016] Preferably, the measured value of the flexible capacitance sensor is only the normal force from the sensing panel module.

[0017] Preferably, a horizontal groove is provided at the bottom of the channel for installing the flexible capacitance sensor assembly.

[0018] Preferably, after receiving the serial port signal, the data processing and analysis system classifies it according to the channel number and converts the capacitance data into pressure data by referring to the capacitance-pressure curve function.

[0019] Preferably, the capacitance-pressure curve function is obtained by fitting through a calibration experiment, and finally the processed data is stored.

[0020] The present invention has the following beneficial effects compared with the prior art:

[0021] (1) The acquisition device of the present invention is interchangeable with the exoskeleton's own structure, which can avoid the influence of the external acquisition device on the working state of the exoskeleton and improve the reliability of human-computer interaction force measurement;

[0022] (2) Through the multiple limit design of the acquisition device of the present invention, the error caused by the flexibility of the human-machine interface can be effectively reduced, and the accuracy and stability of human-computer interaction force measurement can be improved;

[0023] (3) Through the modular design of the sensing panel of the present invention, the customizable and expandable usage mode can adapt to individual differences and improve the repeatability and versatility of human-computer interaction force measurement;

[0024] (4) The present invention adopts a flexible capacitive sensor, which has better durability and foldability. At the same time, the structure of the acquisition device is simple, reducing the overall cost of the measurement system. Brief Description of the Drawings

[0025] Figure 1 is a schematic diagram of the overall solution of the present invention;

[0026] Figure 2 is a schematic diagram of the overall structure of the present invention;

[0027] Figure 3 is a cross-sectional view of the acquisition device of the present invention;

[0028] Figure 4 is a schematic diagram of the working principle of the present invention. Detailed Embodiments

[0029] To make the objectives, technical solutions, and advantages of the present invention clearer, the following will further describe the embodiments of the present invention in detail with reference to the drawings.

[0030] A distributed modular exoskeleton human-computer interaction force measurement system, referring to Figures 1 to 3 , includes a rigid expansion structure 1, a sensing panel module 2, an isolation guide rail 3, a flexible capacitive sensor assembly 4, and a data processing and analysis system 5.

[0031] Referring to Figure 1, taking the knee joint assistive exoskeleton as an example, the rigid expansion structure 1 has the same geometric dimensions as the binding structure of the exoskeleton to be measured, can be assembled and connected to the exoskeleton in the same way, and can be interchanged without changing the state of the exoskeleton itself.

[0032] Furthermore, a number of threaded holes are provided on the inner side of the rigid expansion structure 1 for fixing the isolation guide rail 3; at the same time, a number of circular channels are evenly arranged on the inner side for installing the sensing panel module 2; a horizontal groove is provided at the bottom of the channel for installing the flexible capacitance sensor assembly 4.

[0033] Refer to Figure 2 and Figure 3 , the sensing panel module 2 is a "mushroom-shaped" structure as a whole, with an upper part being a curved surface structure with a large curvature and a lower part being a cylindrical structure. The cylinder is in clearance fit with the circular channel on the rigid expansion structure 1 for fixing itself to the rigid expansion structure 1 and ensuring that the normal of the curved surface is always perpendicular to the human-machine interface, so that the measured value of the flexible capacitance sensor 4 is only the normal force from the sensing panel module 2.

[0034] Refer to Figure 4 , furthermore, the diameter of the lower cylinder of the sensing panel module is consistent with the acquisition range of the flexible capacitance sensor; a number of sensing panel modules 2 can be customarily and arrayedly installed on the inner side of the rigid expansion structure 1 to adapt to individual differences and various measurement requirements.

[0035] Refer to Figure 3 , a number of isolation guide rails 3 are fixedly arranged in parallel on the inner side of the rigid expansion structure 1 to prevent the sensing panel module 2 from falling and limit its rotation around its own axis to reduce the measurement interference caused by the looseness and offset of the relative pose of the exoskeleton with respect to the human body.

[0036] The flexible capacitance sensor assembly 4 includes a flexible capacitance sensor body and an acquisition circuit. The acquisition circuit is based on the STM32L433 chip, cooperates with the PCap01 capacitance acquisition chip to acquire capacitance data, and packages the acquired capacitance data and sends it to the data processing and analysis system through the serial port.

[0037] After receiving the serial port signal, the data processing and analysis system 5 classifies it according to the channel number, converts the capacitance data into pressure data by referring to the capacitance-pressure curve function, and the capacitance-pressure curve function is obtained by fitting through a calibration experiment. Finally, the processed data is stored in the SD card.

[0038] The content not described in detail in the specification of the present invention belongs to the well-known technology of those skilled in the art.

[0039] Although the present invention has been disclosed above with the preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

Claims

1. A distributed modular human-computer interaction force measurement system, characterized in that, It includes a rigid expansion structure, a sensing panel module, an isolation guide rail, a flexible capacitive sensor assembly, and a data processing and analysis system; The external shape and geometric dimensions of the rigid expansion structure are the same as those of the binding structure of the exoskeleton to be measured; several threaded holes are provided on the inner side of the rigid expansion structure for fixing the isolation guide rail, and several channels are evenly arranged on the inner side for installing the sensing panel module; a cavity is provided at the channel of the rigid expansion structure for accommodating the flexible capacitive sensor assembly; The sensing panel module is a mushroom-shaped structure as a whole, with a curved surface structure on the upper part and a cylindrical structure on the lower part. The cylindrical structure is in clearance fit with the channel on the rigid expansion structure, and the end of the cylindrical structure is always in contact with the flexible capacitive sensor; The fixed isolation guide rail is fixedly arranged parallel to the inner side of the rigid expansion structure to prevent the sensing panel module from falling and limit its rotation around its own axis; The flexible capacitive sensor assembly is connected to the data processing and analysis system for acquiring and processing interactive force measurement data.

2. The measurement system according to claim 1, characterized in that, The channel of the rigid expansion structure is circular.

3. The measurement system according to claim 2, characterized in that, The diameter of the lower cylinder of the sensing panel module is the same as the acquisition range of the flexible capacitive sensor assembly.

4. The measurement system according to claim 1, characterized in that, The sensing panel modules are installed on the rigid expansion structure in an array form.

5. The measurement system according to claim 1, characterized in that, The flexible capacitive sensor assembly includes a flexible capacitive sensor body and an acquisition circuit. The acquisition circuit includes an STM32L433 chip and a PCap01 capacitive acquisition chip, which are jointly used to complete the data acquisition of the flexible capacitive sensor body and send the acquired capacitance data in a packet to the data processing and analysis system.

6. The measurement system according to any one of claims 1 to 5, characterized in that, The measured value of the flexible capacitive sensor is only the normal force from the sensing panel module.

7. The measurement system according to any one of claims 1 to 5, characterized in that, A horizontal groove is provided at the bottom of the channel for installing the flexible capacitive sensor assembly.

8. The measurement system according to any one of claims 1 to 5, characterized in that, After receiving the serial port signal, the data processing and analysis system classifies it according to the channel number and converts the capacitance data into pressure data by referring to the capacitance-pressure curve function.

9. The measurement system according to claim 8, characterized in that, The capacitance-pressure curve function is obtained by fitting through a calibration experiment, and finally the processed data is stored.

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