Joint angle adjustment device, adjustment method, and powered exoskeleton
By acquiring and adjusting the angle data of the assisted exoskeleton joints in real time, and controlling the adduction of the second rotational joint, the safety hazards caused by the large degree of freedom of the movable joints are solved, improving the safety and ease of operation of the assisted exoskeleton, and making it suitable for high-intensity work scenarios.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- STATE GRID JIBEI ELECTRIC POWER COMPANY
- Filing Date
- 2024-12-13
- Publication Date
- 2026-06-16
AI Technical Summary
Existing assistive exoskeletons have a large degree of freedom of movement in their joints during wear and use, which makes it easy for the limbs to come into contact with the chest during rotation, posing a safety hazard and increasing the complexity and difficulty of operation.
By acquiring data from the first joint motor, the second joint motor, and the three-dimensional force sensor in real time, the required inward angle of the second joint is determined. The limiting relationship is adjusted by the angle adjustment block and the limiting support surface, thereby controlling the inward angle of the second rotary joint in real time and limiting the inward angle of the second limb structure.
It improves the flexibility and stability of the assistive exoskeleton during lifting heavy objects, reduces operational complexity, and enhances safety. It is particularly suitable for high-intensity work scenarios such as pole lifting operations in the power grid industry, alleviating the labor intensity of workers and improving work efficiency.
Smart Images
Figure CN119820535B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of exoskeleton technology, and in particular to a joint angle adjustment device, a joint angle adjustment method, and an assistive exoskeleton. Background Technology
[0002] In the process of developing this application, the inventors discovered at least the following problems in the prior art: Currently, when existing assistive exoskeletons are worn and used, the movable joints have a degree of freedom to rotate forward and backward as well as a degree of freedom to swing inward and outward. The degree of rotational freedom is relatively large, which can easily cause the limbs to come into contact with the human chest during rotation, posing a safety hazard.
[0003] When working with a power exoskeleton, the operator needs to control the range of motion of the joints to avoid the limbs from contacting the chest during rotation. This undoubtedly increases the complexity of operating the power exoskeleton and the difficulty of using it. Summary of the Invention
[0004] This application aims to at least partially address one of the aforementioned technical problems in the prior art. To this end, embodiments of this application provide a joint angle adjustment device that can control the adduction angle of the second rotary joint in real time, improving compliance and stability during lifting heavy objects and enhancing the safety of the assistive exoskeleton.
[0005] This application also provides a joint angle adjustment method for controlling the aforementioned joint angle adjustment device.
[0006] This application also provides an assistive exoskeleton that uses the above-described joint angle adjustment device.
[0007] According to an embodiment of the first aspect of this application, a joint angle adjustment device is provided, including a limb body, the limb body including a limb body connecting portion; a first rotary joint, the first rotary joint including a first joint connecting block rotatably connected to the limb body connecting portion and a first joint motor mounted on the limb body connecting portion, the drive shaft of the first joint motor being connected to the first joint connecting block to drive the first joint connecting block to rotate back and forth, the first joint motor having a first encoder for acquiring the real-time angle of the first joint motor; a first limb structure, the upper part of the first limb structure being connected to the first joint connecting block to be driven to rotate back and forth by the first joint connecting block; and a second rotary joint, the second rotary joint including a first joint connecting portion connected to the limb body connecting portion. A second joint connecting block is rotatably connected to the lower part of the first limb structure, and a second joint motor is installed at the lower part of the first limb structure. The drive shaft of the second joint motor is connected to the second joint connecting block to drive the second joint connecting block to rotate back and forth. The second joint motor has a second encoder for acquiring the real-time angle of the second joint motor. A second limb structure is formed, with its upper part connected to the second joint connecting block to rotate back and forth driven by the second joint connecting block. The second limb structure is rotatably connected to the second joint connecting block so that the second limb structure can swing inward and outward relative to the second joint connecting block. The second joint connecting block is provided with a third limiting block to limit the angle of inward swing of the second limb structure. A three-dimensional force sensor is directly or indirectly installed at the lower end of the second limb structure; and a joint angle adjustment mechanism is provided with a feedback system for collecting signals from the first encoder, the second encoder, and the three-dimensional force sensor. The feedback signal acquires the real-time angle of the first joint motor, the real-time angle of the second joint motor, and the real-time data of the three-dimensional force sensor to determine the required adduction angle of the second joint. The joint angle adjustment mechanism includes a drive unit installed on the second limb structure and an angle adjustment block connected to the drive unit. The angle adjustment block has a limiting support surface for pressing against the third limiting block. The drive unit drives the angle adjustment block to move, thereby changing the positional relationship between the limiting support surface and the third limiting block, and thus defining the required adduction angle of the second joint.
[0008] According to an embodiment of the first aspect of this application, a joint angle adjustment device is provided, wherein a displacement sensor is directly or indirectly installed on the angle adjustment block to identify the real-time position of the angle adjustment block, and the displacement sensor is communicatively connected to the feedback system.
[0009] According to an embodiment of the first aspect of this application, a joint angle adjustment device is provided, wherein the limiting support surface is an arc surface.
[0010] According to an embodiment of the first aspect of this application, a joint angle adjustment device is provided. The joint angle adjustment mechanism further includes a movable component, which is mounted on a second limb structure via a third sliding assembly so that the movable component can slide along the length direction of the second limb structure. The driving end of the driving unit is connected to one end of the movable component, and the angle adjustment block is disposed at the other end of the movable component.
[0011] According to an embodiment of the first aspect of this application, the driving unit is an electric push rod, which is fixed on the second limb structure, and the driving push rod of the electric push rod is fixed to the moving member.
[0012] According to an embodiment of the first aspect of this application, the joint angle adjustment device further includes the end effector, which is installed at the lower end of the second limb structure, and the three-dimensional force sensor is installed on the end effector.
[0013] According to an embodiment of the second aspect of this application, a joint angle adjustment method is provided, using the joint angle adjustment device described in the first aspect of this application, including the following steps:
[0014] The signal from the first encoder is collected to obtain the real-time angle of the first joint motor; the signal from the second encoder is collected to obtain the real-time angle of the second joint motor; the signal from the three-dimensional force sensor is collected to obtain the real-time data of the three-dimensional force sensor; the required inward angle of the second joint is determined by the real-time angle of the first joint motor, the real-time angle of the second joint motor, and the real-time data of the three-dimensional force sensor.
[0015] Based on the required angle of retraction of the second joint, the target position of the angle adjustment block is determined. The real-time position of the angle adjustment block is obtained through the displacement sensor. The real-time position is compared with the target position. Based on the comparison result of the real-time position and the target position, the driving unit drives the angle adjustment block to move to the target position, thereby defining the required angle of retraction of the second joint.
[0016] According to an embodiment of the second aspect of this application, the adduction requirement angle of the second joint is determined based on a first formula, the first formula being:
[0017] ;
[0018] in, It is from the perspective of the second joint adduction requirement. It is the weight coefficient. It is real-time data from a three-dimensional force sensor. It is the real-time angle of the first joint motor. It is the real-time angle of the second joint motor.
[0019] According to an embodiment of the second aspect of this application, the target position of the angle adjustment block is determined based on a second formula, the second formula being:
[0020] ;
[0021] in, This is the target position data for the angle adjustment block. It is the outer hub length of the second rotary joint. It is the diameter of the angle adjustment block. It is the angle of the second joint adduction requirement.
[0022] According to an embodiment of the third aspect of this application, an assistive exoskeleton is provided, including the joint angle adjustment device described in the embodiment of the first aspect of this application.
[0023] Based on the above technical solution, the embodiments of this application have at least the following beneficial effects: Firstly, by acquiring the real-time angles of the first joint motor, the second joint motor, and the real-time data from the three-dimensional force sensor, the required inward angle of the second joint is determined. Then, the angle adjustment block is moved to change the positional relationship between the limiting support surface and the third limiting block, thereby changing the inward angle limit on the second limb structure and defining the required inward angle of the second joint. This application can control the inward angle limit of the second rotary joint on the second limb structure in real time, improving the compliance and stability during lifting heavy objects, enhancing the safety of the assistive exoskeleton, and is particularly suitable for scenarios requiring high-intensity work, such as pole lifting in the power grid industry, effectively alleviating the labor intensity of workers and improving work efficiency. Attached Figure Description
[0024] The present application will be further described below with reference to the accompanying drawings and embodiments;
[0025] Figure 1 This is a schematic diagram of the structure of the limb body in the embodiments of this application;
[0026] Figure 2 This is a schematic diagram of the joint angle adjustment mechanism in the embodiments of this application;
[0027] Figure 3 This is a cross-sectional view of the joint angle adjustment mechanism in an embodiment of this application;
[0028] Figure 4 This is a front view of the limb body in an embodiment of this application, wherein the included angle between the second limb structure and the second joint connecting block is 180°;
[0029] Figure 5 yes Figure 4 The partial view in direction B;
[0030] Figure 6 This is a schematic diagram of the adduction of the second limb structure in Embodiment 1;
[0031] Figure 7 This is a schematic diagram of the adduction of the second limb structure in Embodiment 2.
[0032] Reference numerals: Limb main body connecting part 100, limb main body connecting seat 111;
[0033] First rotary joint 200, first joint motor 211, first joint connecting block 221, first limiting block 222, second limiting block 223;
[0034] First limb structure 300, upper arm first connecting block 311, upper arm second connecting block 321;
[0035] Second rotary joint 400, second joint motor 411, second joint connecting block 421, third limiting block 422, angle limiting surface 423, fourth limiting block 424;
[0036] Electric push rod 511, moving component 512, slider 513, locking block 514, angle adjusting block 521, limiting support surface 522;
[0037] Second limb structure 600, first connecting block 611 for forearm, slide hole 612, second connecting block 621 for forearm;
[0038] End effector 700. Detailed Implementation
[0039] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.
[0040] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.
[0041] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0042] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.
[0043] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.
[0044] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.
[0045] The following reference Figures 1 to 5 This embodiment describes a joint angle adjustment device, including a limb body, which includes a limb body connecting part 100, a first rotary joint 200, a first limb structure 300, a second rotary joint 400, a joint angle adjustment mechanism, and a second limb structure 600.
[0046] like Figure 1The limb body connection part 100 includes a limb body connection seat 111, which is used to connect with the exoskeleton body.
[0047] The first rotary joint 200 includes a first joint motor 211 and a first joint connecting block 221. The first joint motor 211 is mounted on the limb body connecting part 100, and the first joint connecting block 221 is rotatably connected to the limb body connecting part 100. The drive shaft of the first joint motor 211 is connected to the first joint connecting block 221 to drive the first joint connecting block 221 to rotate back and forth.
[0048] The upper part of the first limb structure 300 is connected to the first joint connecting block 221 so that it can rotate back and forth driven by the first joint connecting block 221.
[0049] like Figure 1 As shown, a three-dimensional orthogonal coordinate system can also be used to describe the movements of the first rotary joint 200 and the first limb structure 300. The X1Y1Z1 coordinate system used to describe the movements of the first rotary joint 200 and the first limb structure 300 is an orthogonal coordinate system containing the X1 axis, Y1 axis, and Z1 axis. Sometimes, the direction parallel to the X1 axis is called the "X1 direction" or "inner / outer direction," the direction parallel to the Y1 axis is called the "Y1 direction" or "front / back direction," and the direction parallel to the Z1 axis is called the "Z1 direction" or "up / down direction." The Y1 axis is orthogonal to the X1 axis, and the Z1 axis is orthogonal to both the X1 and Y1 axes. The drive shaft of the first joint motor 211 is set along the X1 direction. It can be understood that the first joint motor 211 drives the first joint connecting block 221 to rotate back and forth along the X1 axis, and the first joint connecting block 221 drives the first limb structure 300 to rotate back and forth along the X1 axis. It should be emphasized that... Figure 1 The X1Y1Z1 coordinate system is illustrated based on the state where the limb body is completely hanging down. If the first limb structure 300 rotates along the X1 axis, the position of the Y1 axis should also be understood to have changed. This will make the technical solution of this application clearer.
[0050] In some embodiments, the first limb structure 300 has a degree of freedom for inward and outward swinging. Specifically, the first limb structure 300 is rotatably connected to the first joint connecting block 221 about the Y1 axis, and the first limb structure 300 can swing about the Y1 axis. When understanding the solution of this application, Figure 1The presented limb body has the first limb structure 300 fully drooping. At this time, the first joint motor 211 is at a preset zero point position. If the first joint motor 211 drives the first joint connecting block 221 to rotate, the position of the Y1 axis also changes. The Y1 axis can be understood as the hinge axis between the first limb structure 300 and the first joint connecting block 221. In addition, the first joint connecting block 221 is provided with a first limiting block 222 to limit the outward swing angle of the first limb structure 300; the first joint connecting block 221 is provided with a second limiting block 223 to limit the inward retraction angle of the first limb structure 300.
[0051] The second rotary joint 400 includes a second joint connecting block 421 rotatably connected to the lower part of the first limb structure 300 and a second joint motor 411 installed on the lower part of the first limb structure 300. The drive shaft of the second joint motor 411 is connected to the second joint connecting block 421 to drive the second joint connecting block 421 to rotate back and forth.
[0052] The upper part of the second limb structure 600 is connected to the second joint connecting block 421 so that it can rotate back and forth driven by the second joint connecting block 421.
[0053] like Figure 1 As shown, a three-dimensional orthogonal coordinate system can also be used to describe the movements of the second rotary joint 400 and the second limb structure 600. The X2Y2Z2 coordinate system used to describe the movements of the second rotary joint 400 and the second limb structure 600 is an orthogonal coordinate system containing the X2 axis, Y2 axis, and Z2 axis. Sometimes, the direction parallel to the X2 axis is called the "X2 direction" or "inner / outer direction," the direction parallel to the Y2 axis is called the "Y2 direction" or "front / back direction," and the direction parallel to the Z2 axis is called the "Z2 direction" or "up / down direction." The Y2 axis is orthogonal to the X2 axis, and the Z2 axis is orthogonal to both the X2 and Y2 axes. The drive shaft of the second joint motor 411 is set along the X2 direction. It can be understood that the second joint motor 411 drives the second joint connecting block 421 to rotate back and forth along the X2 axis, and the second joint connecting block 421 drives the second limb structure 600 to rotate back and forth along the X2 axis. It should be emphasized that... Figure 1 The X2Y2Z2 coordinate system is illustrated based on the state where the limb body is completely hanging down. If the second limb structure 600 rotates along the X2 axis, the position of the Y2 axis should also be understood to have changed. Furthermore, when the position of the first limb structure 300 changes, the position of the X2Y2Z2 coordinate system also changes. When understanding the technical solution of this application, it should be understood in conjunction with the action and real-time position of each structure.
[0054] Combination Figure 2The second limb structure 600 is rotatably connected to the second joint connecting block 421, allowing the second limb structure 600 to swing inward and outward relative to the second joint connecting block 421, thereby achieving a degree of freedom for the second limb structure 600 to swing inward and outward. (Refer to...) Figure 1 and Figure 2 The second limb structure 600 is rotatably connected to the second joint connecting block 421 around the Y2 axis, and the second limb structure 600 can swing around the Y2 axis. In understanding the solution of this application, Figure 1 The main body of the limb shown is in a position where the second limb structure 600 is completely hanging down. At this time, the second joint motor 411 is in a preset zero position. If the second joint motor 411 drives the second joint connecting block 421 to rotate, the position of the Y2 axis will also change. The Y2 axis can be understood as the hinge axis between the second limb structure 600 and the second joint connecting block 421.
[0055] The second joint connecting block 421 is provided with a third limiting block 422 to limit the inward swing of the second limb structure 600. Specifically, the limiting is achieved by the angle limiting surface 423 of the third limiting block 422. The second joint connecting block 421 is provided with a fourth limiting block 424 to limit the outward swing of the second limb structure 600.
[0056] A three-dimensional force sensor is directly or indirectly installed at the lower end of the second limb structure 600. Specifically, such as... Figure 1 As shown, the joint angle adjustment device also includes an end effector 700, which is installed at the lower end of the second limb structure 600, and a three-dimensional force sensor is installed in the end effector 700.
[0057] The first joint motor 211 has a first encoder for acquiring the real-time angle of the first joint motor 211; the second joint motor 411 has a second encoder for acquiring the real-time angle of the second joint motor 411. The joint angle adjustment mechanism is equipped with a feedback system, which collects signals from the first encoder, the second encoder, and the three-dimensional force sensor. The feedback system acquires the real-time angles of the first and second joint motors and the real-time data from the three-dimensional force sensor to determine the required inward angle of the second joint.
[0058] Combination Figure 2 and Figure 3The joint angle adjustment mechanism includes a drive unit mounted on the second limb structure 600 and an angle adjustment block 521 connected to the drive unit. The angle adjustment block 521 has a limiting support surface 522 for pressing against the third limiting block 422. The drive unit moves the angle adjustment block 521 to change the positional relationship between the limiting support surface 522 and the third limiting block 422. In practical applications, the drive unit is an electric push rod 511, which is fixed on the second limb structure 600. The drive push rod of the electric push rod 511 is fixed to the moving member 512.
[0059] In practical applications, the joint angle adjustment device is suitable for use in upper limb assistive exoskeletons. Specifically, the main body of the limb is the arm, the limb main body connecting part 100 is the arm connecting part, the first rotation joint 200 is the shoulder rotation joint, the first limb structure 300 is the upper arm structure, the second rotation joint 400 is the elbow rotation joint, the joint angle adjustment mechanism is the elbow joint angle adjustment mechanism, the second limb structure 600 is the forearm structure, and the end effector 700 is the hand effector.
[0060] Understandably, when the second limb structure 600 is moved inward around the Y2 axis by the operator, and the limiting support surface 522 of the angle adjustment block 521 contacts the angle limiting surface 423 of the third limiting block 422, the second limb structure 600 can no longer swing inward, thus limiting the angle of adduction of the second rotary joint. (Refer to...) Figure 2 and Figure 3 The electric push rod 511 drives the moving component 512 to move, changing the positional relationship between the limiting support surface 522 and the third limiting block 422. When the second limb structure 600 swings inward around the Y2 axis, the inward angle limit will also change. The technical solution of this application limits the inward angle requirement of the second joint by adjusting the positional relationship between the angle adjusting block 521 and the third limiting block 422.
[0061] In some embodiments, the limiting support surface 522 is an arc surface, which can ensure that the limiting support surface 522 of the angle adjustment block 521 and the angle limiting surface 423 of the third limiting block 422 are in accurate contact, and the contact force of the two surfaces is uniform. Furthermore, when calculating the positional relationship between the limiting support surface 522 and the angle limiting surface 423, the limiting support surface 522 is set as an arc surface, and the distance from the limiting support surface 522 to the axis of the arc surface is constant. Taking the axis of the arc surface as the baseline position, the positional relationship between the axis of the arc surface and the angle limiting surface 423 can be calculated, and the positional relationship between the limiting support surface 522 and the angle limiting surface 423 can be derived. It can also be understood that the arc surface makes it easier to calculate the required angle of the second joint retraction, which facilitates the timely adjustment of the position of the angle adjustment block 521 and limits the required angle of the second joint retraction. Of course, in other embodiments, the angle adjustment block can also be set according to the conventional limiting block structure, that is, the limiting support surface is a plane. However, since the position of the angle adjustment block changes as the second limb structure moves, when the angle adjustment block contacts the third limiting block, the edge of the limiting support surface usually contacts the third limiting block, that is, the corner of the angle adjustment block contacts the angle limiting surface. The force is concentrated on the corner of the angle adjustment block, which can easily cause wear on the corner of the angle adjustment block. It is impossible to calculate the distance to the corner from a certain reference position of the angle adjustment block, which makes it difficult to accurately limit the required angle of the second joint adduction.
[0062] In practical applications, as the load is lifted, the second limb structure 600 needs to gradually retract inward relative to the second rotary joint 400 to move the load closer to the human body. Otherwise, excessive off-center load and instability will occur. Therefore, it is necessary to accurately control the inward angle of the second rotary joint. This application determines the required inward angle of the second joint by acquiring the real-time angles of the first joint motor, the second joint motor, and the real-time data from the three-dimensional force sensor. Then, the angle adjustment block 521 is moved to change the positional relationship between the limiting support surface 522 and the third limiting block 422, thereby changing the inward angle limit of the second limb structure 600 and thus defining the required inward angle of the second joint. This application is applied to an upper limb assistive exoskeleton, which can control the inward angle limit of the second rotary joint 400 on the second limb structure 600 in real time, improving the compliance and stability during lifting heavy objects and enhancing the safety of the upper limb assistive exoskeleton. It is particularly suitable for scenarios requiring high-intensity upper limb work, such as pole lifting in the power grid industry, effectively alleviating the labor intensity of workers and improving work efficiency. Of course, it is not only applicable to the power grid industry, but can also be extended to other fields that require high-intensity upper body work, such as construction and logistics handling.
[0063] Furthermore, the angle adjustment block 521 is directly or indirectly equipped with a displacement sensor to identify the real-time position of the angle adjustment block 521. The displacement sensor is communicatively connected to the feedback system. In the above technical solution, the target position of the angle adjustment block 521 is determined according to the required inward angle of the second joint. Since the position of the angle adjustment block 521 is adjusted in real time, it is necessary to first identify the real-time position of the angle adjustment block 521 through the displacement sensor. The feedback system obtains the real-time position information collected by the displacement sensor, and then, based on the comparison result between the real-time position and the target position, if the comparison result is a difference, the drive unit drives the angle adjustment block 521 to move to the target position, thereby defining the required inward angle of the second joint.
[0064] Specifically, such as Figure 1 As shown, the first limb structure 300 includes a first upper arm connecting block 311 and a second upper arm connecting block 321. The first upper arm connecting block 311 and the second upper arm connecting block 321 are connected by a first sliding assembly. The first sliding assembly may be provided with a first slide rail provided in the first upper arm connecting block 311 and a first slide rail provided in the second upper arm connecting block 321. The first slide rail and the first slide rail cooperate with each other. After the positions of the first upper arm connecting block 311 and the second upper arm connecting block 321 are adjusted, they are then fastened by fasteners. In this way, the length of the first limb structure 300 can be adjusted. Similarly, the second limb structure 600 includes a first forearm connecting block 611 and a second forearm connecting block 621. The first forearm connecting block 611 and the second forearm connecting block 621 are connected by a second sliding assembly. The second sliding assembly may include a second slide rail provided in the first forearm connecting block 611 and a second slide rail provided in the second forearm connecting block 621. The second slide rail and the second slide rail cooperate with each other. After the positions of the first forearm connecting block 611 and the second forearm connecting block 621 are adjusted, they are then fastened together by fasteners. In this way, the length of the second limb structure 600 can be adjusted.
[0065] Reference Figure 2 and Figure 3The joint angle adjustment mechanism also includes a movable component 512, which is mounted on the second limb structure 600 via a third sliding assembly, allowing the movable component 512 to slide along the length of the second limb structure 600. The drive end of the drive unit is connected to one end of the movable component 512, and the angle adjustment block 521 is disposed at the other end of the movable component 512. The third sliding assembly includes a slide hole 612 disposed on the second limb structure 600 and a plurality of sliders 513 disposed on the movable component 512. After passing through the slide hole 612, the sliders 513 are provided with a locking block 514 to restrict the sliders 513 within the slide hole 612. It is understandable that the slide hole 612 is set along the length direction of the first connecting block 611, and the moving member 512 is limited by the slider 513 that extends into the slide hole 612. It can slide along the slide hole 612, that is, along the length direction of the first connecting block 611. When the electric push rod 511 drives the moving member 512 to slide, the angle adjustment block 521 also slides along the length direction of the first connecting block 611, thereby changing the positional relationship with the third limiting block 422.
[0066] This application also discloses an assistive exoskeleton, including the aforementioned joint angle adjustment device.
[0067] This application also discloses a joint angle adjustment method using the aforementioned joint angle adjustment device, comprising the following steps:
[0068] Step S1, align the second rotational joint 400 with the second limb structure 600 at a 180° angle, specifically, the angle between the second limb structure 600 and the second joint connecting block 421 is 180°, such as... Figure 4 As shown.
[0069] Step S2: Acquire the signal from the first encoder to obtain the real-time angle of the first joint motor; acquire the signal from the second encoder to obtain the real-time angle of the second joint motor; acquire the signal from the three-dimensional force sensor to obtain the real-time data of the three-dimensional force sensor.
[0070] The required angle for the retraction of the second joint is determined by the real-time angles of the first joint motor, the second joint motor, and the real-time data from the three-dimensional force sensor; specifically, the required angle for the retraction of the second joint is determined based on the first formula.
[0071] First formula:
[0072] ; in, It is the adduction angle required by the second joint, in degrees (°). It is the weight coefficient, and its dimension is radians per second per Newton (rad·s / N). It is real-time data from a three-dimensional force sensor. It is the derivative of the real-time data of the three-dimensional force sensor with respect to time, and the unit is Newtons per second (N / s). It is the real-time angle of the first joint motor, in degrees (°). It is the real-time angle of the second joint motor, in degrees (°).
[0073] It is a weight factor, related to the load weight. If the load weight is between 0-5kg, =1 rad·s / N; if the load weight is 5-10kg, =1.2 rad·s / N. F is the real-time data from the three-dimensional force sensor, therefore it needs to be differentiated to obtain an accurate value, denoted as . The unit is Newtons per second (N / s). In the first formula, the first term... The calculation result is in radians. Before adding it to the second item, it needs to be multiplied by 180 / π to convert it into an angle value (unit: degrees). The limb body is completely hanging down. At this time, the first joint motor 211 is at the preset zero point position. Then, the real-time angle of the first joint motor is obtained through the first encoder. The second joint motor 411 is at the preset zero point position. Then, the real-time angle of the second joint motor is obtained through the second encoder.
[0074] For example, =10°, =15°, =1 rad·s / N, The value changes by 0.03N within a time interval Δt = 0.1s. At this point, the calculated... =16.95°.
[0075] Step S3: Determine the target position of the angle adjustment block 521 based on the required angle of the second joint retraction. Specifically, the target position of the angle adjustment block 521 is determined based on the second formula.
[0076] Second formula:
[0077] ;in, This is the target position data of the angle adjustment block 521. It is the outer hub length of the second rotating joint, 400. It is the diameter of the angle adjustment block. This refers to the angle of adduction required by the second joint. For example, =50mm, d=13mm, and combined with the above Value, calculated =27.58mm. The outer diameter of the rotating flange portion of the second joint connecting block 421 is equal to the outer hub length of the second rotating joint 400, which can be referenced. Figure 5To understand.
[0078] Then, the real-time position of the angle adjustment block 521 is obtained by the displacement sensor, and the real-time position is compared with the target position. Based on the comparison result between the real-time position and the target position, the electric push rod 511 drives the angle adjustment block 521 to move to the target position, thereby limiting the required angle of the second joint retraction.
[0079] Two different ones are shown below The value corresponds to the required adduction angle of the second joint, and an example is given of the second limb structure reaching the maximum adduction angle at 600°.
[0080] Example 1, refer to Figure 6 At this point, the second joint requires an inward angle. =14.81°, at this time, the limiting support surface 522 of the angle adjustment block 521 contacts the angle limiting surface 423 of the third limiting block 422, and the second limb structure 600 can no longer swing inward, reaching the maximum inward angle.
[0081] Example 2, refer to Figure 7 At this point, the second joint requires an inward angle. =21.96°, at this time, the limiting support surface 522 of the angle adjustment block 521 contacts the angle limiting surface 423 of the third limiting block 422, and the second limb structure 600 can no longer swing inward, reaching the maximum inward angle.
[0082] Both of these embodiments first determine the required angle of adduction for the second joint. The value is then adjusted, and the real-time position of the angle adjustment block 521 is adjusted to reach the target position, thereby limiting the required angle of the second joint retraction.
[0083] The embodiments of this application have been described in detail above with reference to the accompanying drawings. However, this application is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of this application.
Claims
1. A joint angle adjustment device, characterized in that: Includes a limb body, the limb body including Limb main body connection points; A first rotary joint, the first rotary joint including a first joint connecting block rotatably connected to the limb body connecting part and a first joint motor installed on the limb body connecting part, the drive shaft of the first joint motor being connected to the first joint connecting block to drive the first joint connecting block to rotate back and forth, and the first joint motor having a first encoder for acquiring the real-time angle of the first joint motor. A first limb structure, the upper part of which is connected to the first joint connecting block, so that it can rotate back and forth driven by the first joint connecting block; The second rotary joint includes a second joint connecting block rotatably connected to the lower part of the first limb structure and a second joint motor installed on the lower part of the first limb structure. The drive shaft of the second joint motor is connected to the second joint connecting block to drive the second joint connecting block to rotate back and forth. The second joint motor has a second encoder for acquiring the real-time angle of the second joint motor. The second limb structure has its upper part connected to the second joint connecting block so that it can rotate back and forth driven by the second joint connecting block. The second limb structure is rotatably connected to the second joint connecting block so that the second limb structure can swing inward and outward relative to the second joint connecting block. The second joint connecting block is provided with a third limiting block to limit the angle of the inward swing of the second limb structure. A three-dimensional force sensor installed directly or indirectly at the lower end of the second limb structure; as well as A joint angle adjustment mechanism is provided, comprising a feedback system for acquiring signals from the first encoder, the second encoder, and the three-dimensional force sensor. The joint angle adjustment mechanism includes a drive unit mounted on the second limb structure and an angle adjustment block connected to the drive unit. The angle adjustment block has a limiting support surface for pressing against the third limiting block. A displacement sensor is directly or indirectly mounted on the angle adjustment block to identify its real-time position. The displacement sensor is communicatively connected to the feedback system. The feedback system is configured to: determine the required inward angle of the second joint based on the real-time angle of the first joint motor, the real-time angle of the second joint motor, and the real-time data of the three-dimensional force sensor; and determine the target position of the angle adjustment block based on the required inward angle of the second joint. The feedback system is further configured to: acquire the real-time position of the angle adjustment block through the displacement sensor, compare the real-time position with the target position, and control the drive unit to drive the angle adjustment block to move to the target position according to the comparison result, thereby defining the required angle of the second joint retraction.
2. The joint angle adjustment device according to claim 1, characterized in that: The limiting support surface is an arc surface.
3. The joint angle adjustment device according to claim 2, characterized in that: The joint angle adjustment mechanism further includes a moving component, which is mounted on the second limb structure via a third sliding assembly so that the moving component can slide along the length direction of the second limb structure. The driving end of the driving unit is connected to one end of the moving component, and the angle adjustment block is disposed at the other end of the moving component.
4. The joint angle adjustment device according to claim 3, characterized in that: The drive unit is an electric push rod, which is fixed to the second limb structure, and the drive push rod of the electric push rod is fixed to the moving component.
5. The joint angle adjustment device according to any one of claims 2 to 4, characterized in that: The joint angle adjustment device further includes an end effector, which is installed at the lower end of the second limb structure, and the three-dimensional force sensor is installed on the end effector.
6. A method for adjusting a joint angle, characterized in that, Using the joint angle adjustment device according to any one of claims 1 to 5 includes the following steps: The signal from the first encoder is collected to obtain the real-time angle of the first joint motor; the signal from the second encoder is collected to obtain the real-time angle of the second joint motor; the signal from the three-dimensional force sensor is collected to obtain the real-time data of the three-dimensional force sensor; the required inward angle of the second joint is determined by the real-time angle of the first joint motor, the real-time angle of the second joint motor, and the real-time data of the three-dimensional force sensor. Based on the required angle of retraction of the second joint, the target position of the angle adjustment block is determined. The real-time position of the angle adjustment block is obtained through the displacement sensor. The real-time position is compared with the target position. Based on the comparison result of the real-time position and the target position, the driving unit drives the angle adjustment block to move to the target position, thereby defining the required angle of retraction of the second joint.
7. The joint angle adjustment method according to claim 6, characterized in that, The required angle for adduction of the second joint is determined based on the first formula. The first formula is: ； in, It is from the perspective of the second joint adduction requirement. It is the weight coefficient. It is real-time data from a three-dimensional force sensor. It is the real-time angle of the first joint motor. It is the real-time angle of the second joint motor.
8. The joint angle adjustment method according to claim 7, characterized in that, The target position of the angle adjustment block is determined based on the second formula: Second formula: ； in, This is the target position data for the angle adjustment block. It is the outer hub length of the second rotary joint. It is the diameter of the angle adjustment block. It is the angle of the second joint adduction requirement.
9. A power-assisted exoskeleton, characterized in that: Includes the joint angle adjustment device as described in any one of claims 1 to 5.