Knee joint exoskeleton binding comfort evaluation method and device

Abstract

The invention discloses a knee joint exoskeleton binding comfort evaluation method and device. The method comprises the following steps: testing the pressure tolerance limit of the skin surface at the waist and leg interface position of a wearer; respectively collecting surface pressure at a man-machine interface and exoskeleton knee joint movement angle data under two cooperative movement conditions of wearing the knee joint exoskeleton; according to the pressure and angle data, the pressure intensity at a man-machine interface and a man-machine cooperative motion deviation angle are calculated; calculating a local comfort index of each binding part according to the local comfort evaluation model; and according to the local comfort index, calculating the comfort index of the knee joint exoskeleton binding whole body through a global comfort evaluation model. By means of the scheme, the man-machine work efficiency design and product application and popularization of knee joint exoskeleton products can be effectively promoted.

Description

Technical Field

[0001] The present invention generally relates to the field of testing technology, and more specifically, to a method and device for evaluating the comfort of a knee joint exoskeleton binding. Background Art

[0002] The knee exoskeleton robot is a non-embedded wearable intelligent power-assisting device, which is worn on the knee and waist of a person. It can provide external power for knee flexion when the human body is in motion, thereby reducing the metabolic energy consumption during human motion and improving the wearer's physical fitness and endurance. The knee exoskeleton is powered by a portable lithium battery. It uses a variety of sensors to detect the human body's motion state in real time, identify the human body's motion intention, form control instructions based on the characteristics of human motion and the environment, drive the actuators at the joints to move, and convert the battery's electrical energy into joint kinetic energy. The exoskeleton binding is the only physical interface in the human-machine system composed of the wearer and the exoskeleton robot. It is a two-way power and information flow channel for the exoskeleton to transmit force to the human body, and for the human body's motion to transmit to the exoskeleton. It is an important component of the exoskeleton and directly affects the performance of the exoskeleton and the subjective feeling of wearing.

[0003] The design of the knee exoskeleton binding takes into account the performance of the physical interface and gradually introduces the concept and method of human factors engineering design to improve the comfort of wearing the exoskeleton equipment. Since the binding materials are mostly fabrics, foam and other materials, and the surface muscles of the human body have a certain elasticity, the current evaluation test of the binding design lacks methods for evaluating comfort and related testing devices, resulting in insufficient evaluation accuracy and lack of objectivity.

[0004] Among the patents and prototypes of knee exoskeleton robots that have been published, there are currently no testing methods and detection devices for exoskeleton comfort. Therefore, how to objectively evaluate the comfort of the human body when wearing a knee exoskeleton and design related equipment to detect the force interaction between humans and machines is an important tool to improve the comfort of exoskeleton wearing, which can strongly support the ergonomic design of exoskeletons and become a technical problem that needs to be solved in the field of exoskeleton robots. Summary of the invention

[0005] In order to at least solve the technical problems described in the above background technology section, the present invention proposes a method and device for evaluating the comfort of knee exoskeleton binding. Utilizing the solution of the present invention, the interactive force between the wearer and the exoskeleton in the binding position under two coordinated motion modes is comprehensively considered, and at the same time, the key angle deviation of the exoskeleton before and after the power assist is introduced, so that the exoskeleton binding comfort evaluation takes into account both the wearing comfort and the power assist effect. In view of this, the present invention provides solutions in the following aspects.

[0006] The first aspect of the present invention provides a method for evaluating the comfort of a knee exoskeleton binding, comprising: testing the pressure tolerance limit of the skin surface at the waist and leg interface of the wearer; respectively collecting the surface pressure at the human-machine interface and the exoskeleton knee joint movement angle data under two coordinated motion conditions of wearing a knee exoskeleton; the two coordinated motion conditions include a condition where the exoskeleton joint mechanism does not provide additional assistance and a condition where the exoskeleton joint mechanism provides additional assistance; based on the pressure and angle data, calculating the average pressure at the human-machine interface and the deviation angle of the human-machine coordinated motion; based on the average pressure, the motion deviation angle and the pressure tolerance limit, calculating the local comfort index of each binding point through a local comfort evaluation model; based on the local comfort index, calculating the overall comfort index of the knee exoskeleton binding through a global comfort evaluation model.

[0007] In one embodiment, the test of the pressure tolerance limit of the skin surface at the waist and leg interface of the wearer includes: testing the tolerable pressure P that the skin surface at the contact position between the human leg and the exoskeleton binding can accept when the human body is lying flat or lying prone. ei , and according to the pressure resistance P ei and contact area to calculate the maximum pressure F that the surface skin can accept ei .

[0008] In one embodiment, the surface pressure at the human-machine interface and the exoskeleton knee joint motion angle data are collected respectively when the wearer is wearing a knee joint exoskeleton in two coordinated motion situations, including: collecting the surface pressure F at the contact position between the human leg and the exoskeleton binding when the wearer is standing upright and the exoskeleton joint mechanism is not assisted in coordinated motion ij and the exoskeleton joint angle θ L ,θ R , where i represents the i-th binding position of the leg, j represents the j-th measurement point of the i-th binding position, θ L represents the exoskeleton joint angle of the left foot during unassisted collaborative motion, θ R represents the exoskeleton joint angle of the right foot during non-assisted collaborative motion; collects the surface pressure G at the contact position between the human leg and the exoskeleton binding when the wearer is standing upright and the exoskeleton joint mechanism is assisted in collaborative motion ij and the exoskeleton joint angle θ PL ,θ PR , where i represents the i-th binding position of the leg, j represents the j-th measurement point of the i-th binding position, θ PL represents the exoskeleton joint angle of the left foot during the assisted coordinated movement, θ PR Represents the exoskeleton joint angle of the right foot during the power-assisted coordinated movement.

[0009] In one embodiment, the calculation of the average pressure at the human-machine interface and the deviation angle of the human-machine collaborative motion according to the pressure and angle data includes calculating the average surface pressure F at the contact position between the human leg and the exoskeleton binding using the following formula: mij And the joint deviation angle Δθ:

[0010]

[0011] Among them, i represents the i-th binding position of the leg, and j represents the j-th measuring point at the i-th binding position.

[0012] In one embodiment, the local comfort index of each binding point is calculated by a local comfort evaluation model according to the average pressure, the movement deviation angle and the pressure tolerance limit, including calculating the local comfort index ε using the following formula: i :

[0013]

[0014] Wherein, i=1,2,3... represents the i-th binding, K1 represents the first weighting coefficient, and K2 represents the second weighting coefficient.

[0015] In one embodiment, the overall comfort index of the knee joint exoskeleton binding is calculated by using a global comfort evaluation model according to the local comfort index, including calculating the global comfort index ψ using the following formula:

[0016]

[0017] Wherein, N is the total number of exoskeleton bindings, K3 represents the third weighting coefficient, and K4 represents the fourth weighting coefficient.

[0018] The second aspect of the present invention also provides a knee exoskeleton binding comfort assessment device, which is used to run any of the above-mentioned knee exoskeleton binding comfort assessment methods, including: a dot matrix film pressure sensor, used to collect pressure data of the knee exoskeleton on the human body; a data acquisition unit, used to perform signal processing on the collected pressure data; a host computer, used to connect to the data acquisition unit to calculate a comfort index based on the result of the signal processing.

[0019] In one embodiment, the diameter of the measuring points of the dot matrix thin film pressure sensor is no more than 10 mm, the spacing is no more than 15 mm, and the size and shape are the same as the binding shape.

[0020] In one embodiment, the distance between the measuring point and the edge is not less than 10 mm.

[0021] In one embodiment, the data acquisition unit transmits data to the host computer via bus networking.

[0022] The solution provided by the present invention, on the one hand, comprehensively considers the interactive force of the binding position between the wearer and the exoskeleton in two coordinated motion modes, and at the same time introduces the key angle deviation of the exoskeleton before and after the power-assistance, so that the exoskeleton binding comfort evaluation takes into account both the wearing comfort and the power-assistance effect; on the other hand, the comfort evaluation model based on the pressure tolerance limit of the wearer's skin surface can take into account the characteristics of different types of tasks and the different pressure tolerance of users, and has good applicability. In addition, a test device for regional pressure provided by the present invention can detect the human-computer interaction force at the binding point by designing a dot matrix flexible pressure sensor matrix, and has good adaptability to the human body surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] By reading the following detailed description with reference to the accompanying drawings, the above and other objects, features and advantages of the exemplary embodiments of the present invention will become readily understood. In the accompanying drawings, several embodiments of the present invention are shown in an exemplary and non-limiting manner, and the same or corresponding reference numerals represent the same or corresponding parts, wherein:

[0024] Figure 1 It is a method for evaluating the comfort of an exoskeleton binding according to an embodiment of the present invention;

[0025] Figure 2 is a schematic diagram showing an exoskeleton structure according to an embodiment of the present invention;

[0026] Figure 3 FIG. 2 is a diagram showing an exoskeleton binding comfort evaluation device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0028] It should be understood that the terms "first", "second", "third" and "fourth" etc. in the claims, specifications and drawings of the present invention are used to distinguish different objects rather than to describe a specific order. The terms "include" and "comprise" used in the specification and claims of the present invention indicate the presence of the described features, wholes, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or their collections.

[0029] It should also be understood that the terms used in this specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the specification of the present invention and the claims, the singular forms of "a", "an" and "the" are intended to include the plural forms unless the context clearly indicates otherwise. It should also be further understood that the term "and / or" used in the specification of the present invention and the claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes these combinations.

[0030] As used in this specification and claims, the term "if" may be interpreted as "when" or "upon" or "in response to determining" or "in response to detecting," depending on the context. Similarly, the phrase "if it is determined" or "if [described condition or event] is detected" may be interpreted as meaning "upon determination" or "in response to determining" or "upon detection of [described condition or event]" or "in response to detecting [described condition or event]," depending on the context.

[0031] The specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0032] The first aspect of the present invention provides a method for evaluating the comfort of knee exoskeleton binding. The exoskeleton is bound to the human body in a non-embedded manner to form a coupled human-machine system with the human body. How to achieve that the exoskeleton provides additional assistance to the wearer while ensuring comfort when worn, and does not cause physical damage and subjective discomfort to the wearer is an important part of the exoskeleton ergonomic design. The locations where the knee exoskeleton interacts with the wearer through binding are mainly concentrated in the waist and legs, among which the leg bindings are the most numerous and are also the main force transmission interface.

[0033] A knee exoskeleton binding comfort evaluation method proposed in the present invention can provide a knee exoskeleton binding comfort evaluation index according to the personalized differences of the wearer by collecting objective test data and using local and global evaluation models, thereby providing objective support for the knee exoskeleton binding comfort evaluation, which is of great significance to the ergonomic design of knee exoskeleton products and the promotion and application of products.

[0034] Figure 1 FIG. 2 is a diagram showing an exoskeleton binding comfort evaluation method according to an embodiment of the present invention. The exoskeleton binding comfort evaluation method can be described as comprising steps S100-S500:

[0035] Step S100: testing the pressure tolerance limit of the skin surface at the waist and leg interface of the wearer;

[0036] Step S200: respectively collecting surface pressure at the human-machine interface and exoskeleton knee joint motion angle data when wearing a knee joint exoskeleton in two coordinated motion situations;

[0037] Step S300: Calculating the average pressure at the human-machine interface and the deviation angle of human-machine collaborative motion according to the pressure and angle data;

[0038] Step S400: calculating the local comfort index of each binding point through a local comfort evaluation model according to the average pressure, the movement deviation angle and the pressure tolerance limit value;

[0039] Step S500: Calculate the overall comfort index of the knee joint exoskeleton binding using a global comfort evaluation model based on the local comfort index.

[0040] The above two coordinated motion situations include a situation where the exoskeleton joint mechanism does not provide additional assistance and a situation where the exoskeleton joint mechanism provides additional assistance.

[0041] In one embodiment of the present invention, the above-mentioned test of the pressure tolerance limit of the skin surface at the waist and leg interface of the wearer includes:

[0042] Test the pressure resistance P that the skin on the surface of the human leg in contact with the exoskeleton binding can withstand when the human body lies flat or prone. ei , and according to the pressure resistance P ei and contact area to calculate the maximum pressure F that the surface skin can accept ei .

[0043] In one embodiment of the present invention, the above-mentioned data of surface pressure at the human-machine interface and exoskeleton knee joint motion angle under two coordinated motion conditions of wearing a knee joint exoskeleton respectively include:

[0044] Collect the surface pressure F at the contact position between the human leg and the exoskeleton binding when the wearer stands upright and the exoskeleton joint mechanism moves in a non-assisted collaborative manner ij and the exoskeleton joint angle θ L ,θ R , where i represents the i-th binding position of the leg, j represents the j-th measurement point of the i-th binding position, θ L represents the exoskeleton joint angle of the left foot during unassisted collaborative motion, θ R represents the exoskeleton joint angles of the right foot during unassisted collaborative motion;

[0045] Collect the surface pressure G at the contact position between the human leg and the exoskeleton binding when the wearer stands upright and the exoskeleton joint mechanism assists in coordinated movement ij and the exoskeleton joint angle θ PL ,θ PR, where i represents the i-th binding position of the leg, j represents the j-th measurement point of the i-th binding position, θ PL represents the exoskeleton joint angle of the left foot during the assisted coordinated movement, θ PR Represents the exoskeleton joint angle of the right foot during the power-assisted coordinated movement.

[0046] Attached Figure 2 FIG. 1 is a schematic diagram showing the structure of an exoskeleton according to an embodiment of the present invention. Figure 2 The exoskeleton is adapted to the human knee joint, and includes a fixed part and a movable part. The fixed part refers to the part tied to the human calf and thigh, and the movable part refers to the part corresponding to the knee. The movable part will bend at an angle when the human body wears the exoskeleton.

[0047] In one embodiment of the present invention, the calculation of the average pressure at the human-machine interface and the deviation angle of the human-machine collaborative motion according to the pressure and angle data includes calculating the average surface pressure F at the contact position between the human leg and the exoskeleton binding using the following formula: mij And the joint deviation angle Δθ:

[0048]

[0049] Among them, i represents the i-th binding position of the leg, and j represents the j-th measuring point at the i-th binding position.

[0050] In one embodiment of the present invention, the local comfort index of each binding point is calculated by a local comfort evaluation model according to the average pressure, the movement deviation angle and the pressure tolerance limit value, including calculating the local comfort index ε using the following formula: i :

[0051]

[0052] Wherein, i=1,2,3... represents the i-th binding, K1 represents the first weighting coefficient, and K2 represents the second weighting coefficient.

[0053] In one embodiment of the present invention, the overall comfort index of the knee joint exoskeleton binding is calculated by a global comfort evaluation model based on the local comfort index, including calculating the global comfort index ψ using the following formula:

[0054]

[0055] Wherein, N is the total number of exoskeleton bindings, K3 represents the third weighting coefficient, and K4 represents the fourth weighting coefficient.

[0056] Figure 3FIG. 2 is a diagram showing an exoskeleton binding comfort evaluation device according to an embodiment of the present invention. Figure 3 As shown, the second aspect of the present invention provides a method for evaluating the comfort of a knee joint exoskeleton binding, which is used to run any of the above-mentioned methods for evaluating the comfort of a knee joint exoskeleton binding, comprising:

[0057] A dot matrix thin film pressure sensor 100 is used to collect pressure data of the knee joint exoskeleton on the human body;

[0058] The data acquisition unit 200 is used to perform signal processing on the collected pressure data;

[0059] The host computer 300 is used to connect with the data acquisition unit to calculate the comfort index according to the result of the signal processing.

[0060] In one embodiment of the present invention, the diameter of the measuring points of the dot matrix thin film pressure sensor is no more than 10 mm, the spacing is no more than 15 mm, and the size and shape are the same as the binding shape.

[0061] In one embodiment of the present invention, the distance between the measuring point and the edge is not less than 10 mm.

[0062] In one embodiment of the present invention, the data acquisition unit transmits data to the host computer via bus networking.

[0063] Although this specification has shown and described a plurality of embodiments of the present invention, it is obvious to those skilled in the art that such embodiments are provided by way of example only. Those skilled in the art will appreciate many changes, modifications and alternatives without departing from the thought and spirit of the present invention. It should be understood that in the process of practicing the present invention, various alternatives to the embodiments of the present invention described herein may be adopted. The attached claims are intended to define the scope of protection of the present invention, and therefore cover the modular compositions, equivalents or alternatives within the scope of these claims.

Claims

1. A method for evaluating the comfort of knee joint exoskeleton binding, characterized in that: include; Test the pressure tolerance limit of the skin surface at the waist and leg interface of the wearer; The surface pressure at the human-machine interface and the exoskeleton knee joint movement angle data are respectively collected in two coordinated motion situations of wearing the knee joint exoskeleton; the two coordinated motion situations include a situation where the exoskeleton joint mechanism does not provide additional assistance and a situation where the exoskeleton joint mechanism provides additional assistance; Calculate the average pressure at the human-machine interface and the deviation angle of human-machine collaborative motion according to the pressure and angle data; Calculating the local comfort index of each binding point through a local comfort evaluation model according to the average pressure, the movement deviation angle and the pressure tolerance limit value; According to the local comfort index, the overall comfort index of the knee joint exoskeleton binding is calculated through a global comfort evaluation model.

2. The knee joint exoskeleton binding comfort evaluation method according to claim 1, characterized in that: The test of the pressure tolerance limit of the skin surface at the waist and leg interface of the wearer includes: Test the pressure resistance P that the skin on the surface of the human leg in contact with the exoskeleton binding can withstand when the human body lies flat or prone. ei , and according to the pressure resistance P ei and contact area to calculate the maximum pressure F that the surface skin can accept ei .

3. The knee joint exoskeleton binding comfort evaluation method according to claim 1, characterized in that: The data of surface pressure at the human-machine interface and exoskeleton knee joint motion angle under two coordinated motion conditions of wearing a knee joint exoskeleton are collected respectively, including: Collect the surface pressure F at the contact position between the human leg and the exoskeleton binding when the wearer stands upright and the exoskeleton joint mechanism moves in a non-assisted collaborative manner ij and the exoskeleton joint angle θ L ,θ R , where i represents the i-th binding position of the leg, j represents the j-th measurement point of the i-th binding position, θ L represents the exoskeleton joint angle of the left foot during unassisted collaborative motion, θ R represents the exoskeleton joint angles of the right foot during unassisted collaborative motion; Collect the surface pressure G at the contact position between the human leg and the exoskeleton binding when the wearer stands upright and the exoskeleton joint mechanism assists in coordinated movement ij and the exoskeleton joint angle θ PL ,θ PR , where i represents the i-th binding position of the leg, j represents the j-th measurement point of the i-th binding position, θ PL represents the exoskeleton joint angle of the left foot during the assisted coordinated movement, θ PR Represents the exoskeleton joint angle of the right foot during the power-assisted coordinated movement.

4. The knee joint exoskeleton binding comfort evaluation method according to claim 3, characterized in that: The average pressure at the human-machine interface and the deviation angle of human-machine collaborative motion are calculated based on the pressure and angle data, including calculating the average surface pressure F at the contact position between the human leg and the exoskeleton binding using the following formula: mij And the joint deviation angle Δθ: Among them, i represents the i-th binding position of the leg, and j represents the j-th measuring point at the i-th binding position.

5. The knee joint exoskeleton binding comfort evaluation method according to claim 4, characterized in that: The local comfort index of each binding point is calculated by a local comfort evaluation model according to the average pressure, the movement deviation angle and the pressure tolerance limit value, including calculating the local comfort index ε using the following formula: i : Wherein, i=1,2,3... represents the i-th binding, K1 represents the first weighting coefficient, and K2 represents the second weighting coefficient.

6. The knee joint exoskeleton binding comfort evaluation method according to claim 5, characterized in that: The overall comfort index of the knee joint exoskeleton binding is calculated based on the local comfort index through the global comfort evaluation model, including calculating the global comfort index ψ using the following formula: Wherein, N is the total number of exoskeleton bindings, K3 represents the third weighting coefficient, and K4 represents the fourth weighting coefficient.

7. A knee joint exoskeleton binding comfort evaluation device, used for running the knee joint exoskeleton binding comfort evaluation method as described in any one of claims 1 to 6, characterized in that: include: Dot matrix thin film pressure sensor, used to collect pressure data of knee exoskeleton on human body; A data acquisition unit, used for performing signal processing on the collected pressure data; A host computer is used to connect with the data acquisition unit to calculate the comfort index according to the result of the signal processing.

8. A knee joint exoskeleton binding comfort evaluation device according to claim 7, characterized in that: The measuring point diameter of the dot matrix thin film pressure sensor is no more than 10 mm, the spacing is no more than 15 mm, and the size and shape are the same as the binding appearance.

9. A knee joint exoskeleton binding comfort evaluation device according to claim 8, characterized in that: The distance between the measuring point and the edge is not less than 10 mm.

10. A knee joint exoskeleton binding comfort evaluation device according to any one of claims 7 to 9, characterized in that: The data acquisition unit transmits data to the host computer via bus networking.

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