A multi-modal joint assist exoskeleton robot and method of use

Abstract

This invention belongs to the field of robotics technology, specifically relating to a multimodal joint-assisted exoskeleton robot and its usage method. The multimodal joint-assisted exoskeleton robot includes a back adjustment mechanism, which comprises a back fixing plate. A mounting plate is disposed on the rear side of the back fixing plate. A first pneumatic muscle is symmetrically fixed on the left and right sides of the lower part of the mounting plate. A first connecting rod is connected to the lower end of the first pneumatic muscle via a first angle adjuster. A second pneumatic muscle is hinged to the other end of the first connecting rod. A coordinating connecting rod is hinged between the upper ends of the two second pneumatic muscles on the left and right sides. This invention achieves the associated control of the left and right connecting rod mechanisms through the coordinating connecting rod, accurately simulating the coordinated relationship of the left and right joints in natural human activity. This solves the problem of existing single-arm or independent drive devices being disconnected from real-life scenarios, thus improving the assistive effect.

Description

Technical Field

[0001] This invention belongs to the field of robotics technology, specifically relating to a multimodal joint-assisted exoskeleton robot and its usage method. Background Technology

[0002] In the current field of joint assistive and exoskeleton technology, a variety of assistive devices and exoskeleton systems have emerged to meet the joint mobility assistance needs of people with weak limb mobility. However, these technical solutions still have significant limitations in practical applications and are difficult to meet the needs of efficient, safe and universal use.

[0003] From a driving perspective, mainstream electric joint assist devices generally face the dual challenges of electromagnetic interference and maintenance costs. These devices rely on electric components such as motors and reducers for driving force. The electromagnetic signals generated by the motors during operation can easily interfere with surrounding precision electronic equipment. In industrial auxiliary scenarios, this can lead to distorted sensor data on the production line, misinterpretation of programmable logic controller (PLC) instructions, and equipment malfunctions. In outdoor operations or daily auxiliary scenarios, it may interfere with satellite positioning equipment and communication terminals, affecting safety and task execution efficiency. Furthermore, after long-term, high-frequency use, the electric components experience high rates of mechanical wear and electrical failures. Repairs require specialized technicians and spare parts, not only extending equipment downtime but also significantly increasing long-term operating costs, making it unaffordable for small businesses, grassroots service teams, and ordinary households, thus limiting the technology's widespread adoption.

[0004] In terms of motion coordination design, most joint assistive devices suffer from the deficiency of unilateral drive or bilateral independent movement, which is out of sync with the natural movement patterns of the human body. When the human body performs daily actions (such as picking up objects, carrying, and extending limbs), the movement of the joints on both sides often exhibits a coordinated and linked relationship. For example, when one limb is raised, the opposite limb needs to adjust its posture to maintain balance. However, in existing devices, single-arm / single-limb drive designs can only realize the movement of one joint and cannot simulate bilateral coordinated movements. Even if some devices have bilateral drive functions, they mostly adopt a mode of separate control of the two limbs, without establishing a correlation mechanism between bilateral movements. This results in stiff assistive movements that do not conform to human movement habits, which not only reduces user comfort but may also increase the burden on limb muscles due to uncoordinated movements, making it difficult to help users form natural movement patterns.

[0005] In terms of range of motion and degree of freedom coverage, existing devices struggle to achieve large-scale, multi-degree-of-freedom complex movements of joints. Most common joint assistive devices are simple single-degree-of-freedom movement assistive structures, capable of only performing single movements such as flexion, extension, and rotation. They cannot simulate the complex movement trajectories of human joints. Taking key limb joints as an example, their normal activities need to cover multiple dimensions such as abduction, adduction, flexion, extension, internal rotation, and external rotation. However, due to structural design limitations, the range of motion of existing devices is usually compressed by 30%-50%, and it is difficult to achieve smooth transitions between multi-degree-of-freedom movements. They cannot effectively help users restore or improve their limb mobility, especially failing to meet the assistance needs of complex daily actions (such as dressing, organizing items, and operating tools).

[0006] Insufficient safety and adaptability in human-computer interaction is another prominent problem with existing devices. Most joint assist devices use rigid transmission structures and lack compliant adjustment mechanisms. During contact with and power transmission to the human limb, it is difficult to adjust the force in real time according to changes in limb posture, which can easily cause discomfort due to movement deviations or improper force control. For users with high limb sensitivity, it may even cause secondary injuries such as collisions and compression. At the same time, it can only adapt to different body types through a limited number of adjustment levels, and cannot accurately match individual differences in limb length and joint range of motion. This leads to problems such as poor device fit to the limb and low motion transmission efficiency for some users, further limiting the range of people to whom the device is applicable.

[0007] In terms of structural design and spatial adaptability, traditional joint assistive devices generally suffer from being bulky and excessively heavy. To achieve multi-degree-of-freedom actuation, these devices often require complex transmission mechanisms and drive components, resulting in an overall weight far exceeding the human body's comfort threshold. Prolonged wear can easily cause strain on the shoulders, waist, and other areas. At the same time, these devices occupy a large space, making them difficult to place and use flexibly in confined environments such as homes and small offices. Furthermore, their lack of portability design fails to meet users' needs for transferring the devices between different scenarios, further reducing the practical application value of the technology. Summary of the Invention

[0008] This invention addresses the aforementioned problems by providing a multimodal joint-assisted exoskeleton robot and its usage method.

[0009] To achieve the above objectives, the present invention employs the following technical solution:

[0010] A multimodal joint-assisted exoskeleton robot includes a back adjustment mechanism. The back adjustment mechanism includes a back fixation plate, a back fixation frame on the upper surface of the back fixation plate, and fixing straps on both the back fixation plate and the back fixation frame. Adjacent fixing straps are fixedly connected by buckles. A mounting plate is provided on the rear side of the back fixation plate. A first pneumatic muscle is symmetrically fixed on the left and right sides of the lower part of the mounting plate. The first pneumatic muscle is vertically positioned. A first link is connected to the lower end of the first pneumatic muscle via a first angle adjuster. A second pneumatic muscle is hinged to the other end of the first link. A second link is connected to the middle of the first link via a second angle adjuster. A third pneumatic muscle is hinged to the other end of the second link. A third link is hinged to the upper end of the second pneumatic muscle. The other end of the third link is hinged to the upper end of the first pneumatic muscle. A fourth link is hinged to the middle of the third link. The other end of the fourth link is connected to the third pneumatic muscle. The upper end of the pneumatic muscle is hinged, and the upper end of the third pneumatic muscle is fixedly connected to the lower end of the L-shaped rod. A coordinating link is hinged between the upper ends of the two second pneumatic muscles on the left and right sides. The coordinating link includes a telescopic outer rod and a telescopic inner rod. The telescopic inner rod is slidably disposed inside the telescopic outer rod. A groove is provided on the telescopic outer rod, and a cylindrical slider is slidably disposed in the groove. The cylindrical slider is fixedly connected to a guide rod, which is slidably disposed in a guide groove on the mounting plate. A connecting block is fixedly disposed on the upper part of the guide rod. The lower end of the connecting block is fixedly connected to the upper end of the fourth pneumatic muscle. The lower end of the fourth pneumatic muscle is fixedly connected to the mounting plate. A first traction rope is fixedly connected to the upper end of the connecting block. The other end of the first traction rope passes around the upper end of the back fixation frame and connects to the upper end of the fifth pneumatic muscle. The lower end of the fifth pneumatic muscle is mounted on the back fixation plate. A shoulder mechanism is mounted on the upper end of the L-shaped rod, and a large arm mechanism is mounted on the outside of the shoulder mechanism.

[0011] Furthermore, the shoulder mechanism includes a shoulder fitting frame, with a connecting strap below the shoulder fitting frame to fix the shoulder fitting frame to the human shoulder. A square connector is rotatably connected to the front end of the shoulder fitting frame. An outer lower guide wheel, an inner lower guide wheel, an inner upper guide wheel, and an outer upper guide wheel are respectively provided at the four corners of the front face of the square connector. A second traction rope is fixedly installed on the outer lower guide wheel. The other end of the second traction rope passes sequentially around the inner lower guide wheel, the inner upper guide wheel, the outer upper guide wheel, multiple thread guide wheels, and the upper part of the back fixation frame, and is fixedly connected to the upper end of the abduction pneumatic muscle. The lower end of the abduction pneumatic muscle is installed on the back fixation plate. Multiple thread guide wheels are respectively installed on the upper surface of the shoulder fitting frame. An arc-shaped connector is rotatably connected to the outer end of the square connector. A spherical connector is fixedly installed on the outer end of the arc-shaped connector. An upper arm mechanism is installed on the spherical connector.

[0012] Furthermore, the upper arm mechanism includes a muscle fixation seat hinged to the upper end of a spherical connector. An outer upper arm rod is hinged to the outside of the spherical connector, and an inner upper arm rod is slidably disposed inside the outer upper arm rod. The outer and inner upper arm rods are fixedly connected by bolts. An upper arm fitting frame is fixedly disposed on the inner side of the upper part of the inner upper arm rod, and an upper arm strap is disposed on the fitting frame. A functional ring is fixedly connected to the outer side of the upper part of the inner upper arm rod. The functional ring is also fixedly connected to the upper surface of a connecting ring. A receiving groove is formed on the functional ring, and fixing posts are provided at both ends of the receiving groove. The fixing posts are fixedly connected to the functional ring. Annular guide rings are provided on both the upper and lower surfaces of the connecting ring. The upper annular guide ring has a notch for a No. 3 traction rope to pass through. A capping ring and a base ring are respectively provided at the top and bottom. Both the capping ring and the base ring have annular guide grooves corresponding to the annular guide rings. Two outlet reversing wheels and a right-angle reversing component are provided on the base ring, with the two outlet reversing wheels located between the two right-angle reversing components. A notch is provided on the capping ring to allow space for the outlet reversing wheels and the right-angle reversing components. A rotating pneumatic muscle is provided above the right-angle reversing component. The upper end of the rotating pneumatic muscle is connected to the muscle fixing seat via a Hooke's hinge. A No. 3 traction rope is fixedly connected to the lower end of the rotating pneumatic muscle. The No. 3 traction rope passes through the corresponding right-angle reversing component and the outlet reversing wheel and is connected to the corresponding fixing post. Swing arm pneumatic muscles are connected to the front and rear sides of the muscle fixing seat via Hooke's hinges. The lower end of the swing arm pneumatic muscles is connected to the capping ring via a Hooke's hinge.

[0013] Furthermore, the first, second, third, and fourth links are all curved rods to prevent interference between them.

[0014] Furthermore, the mounting plate is connected to the back fixing plate via multiple ball joints to achieve adaptive adjustment of the mounting plate's posture.

[0015] Furthermore, a spring is provided between the outer end of the square connector and the shoulder fitting frame.

[0016] A method of using a multimodal joint-assisted exoskeleton robot includes upper arm internal / external rotation, upper arm swinging, upper arm abduction, and shoulder adjustment movements;

[0017] Upper arm internal / external rotation movement: The upper arm inner bar is fixed to the upper arm of the human body through the upper arm fitting frame and upper arm strap. One of the rotating pneumatic muscles shortens, driving the corresponding No. 3 traction rope to rise, which in turn pulls the functional ring and connecting ring to rotate. The other rotating pneumatic muscle extends, lowering the No. 3 traction rope connected to it, so as to realize the coordination of the rotation of the functional ring and connecting ring. The rotation of the functional ring and connecting ring drives the upper arm to perform internal / external rotation movement.

[0018] Upper arm swinging motion: When the pneumatic muscles on the front side of the arm shorten and the pneumatic muscles on the back side of the arm lengthen, the upper arm swings forward; conversely, when the pneumatic muscles on the front side of the arm lengthen and the pneumatic muscles on the back side of the arm shorten, the upper arm swings backward.

[0019] Upper arm abduction movement: When the abduction pneumatic muscle shortens, it pulls the second traction rope, which drives the square connector to rotate. Since the other end of the square connector is connected to the upper arm mechanism through the arc connector and the ball connector, it ultimately drives the upper arm mechanism and the human upper arm to achieve abduction movement. When the upper arm does not need to be abducted, the abduction pneumatic muscle extends, and the upper arm mechanism and the human upper arm fall under their own weight and the action of the spring.

[0020] Shoulder Adjustment Movement: When the position of the shoulder fitting frame needs to be adjusted according to the body size, the angle between the first pneumatic muscle and the first connecting rod is adjusted using the first angle adjuster, and the angle between the first and second connecting rods is adjusted using the second angle adjuster, thus achieving an initial adjustment of the shoulder fitting frame position. Then, the first, second, and third pneumatic muscles on both sides move collaboratively to achieve fine-tuning of the shoulder fitting frame position on both sides. Simultaneously, the fourth and fifth pneumatic muscles follow suit to adapt to the adjustment of the shoulder fitting frame position. During operation, when the left and right shoulders need to move collaboratively (i.e., one side raises and the other lowers), the fourth and fifth pneumatic muscles work together to ensure the height of the cylindrical slider remains constant. This is achieved by adjusting one side... The lengths of pneumatic muscles #1, #2, and #3 cause the shoulder on that side to rise. Due to the limiting effect of the cylindrical slider on the coordinating link, the other side of the coordinating link sinks under the lever principle. At the same time, pneumatic muscles #1, #2, and #3 on the other side move synchronously, causing the shoulder on that side to sink, completing the coordinated movement of the left and right shoulders. During operation, when only one shoulder needs to move, pneumatic muscles #1, #2, and #3 on that side change their lengths, causing the shoulder to move. At the same time, the movement of pneumatic muscle #2 will cause the coordinating link to move. In this case, in order to ensure that the position of the other end of the coordinating link does not change, pneumatic muscles #4 and #5 need to move in coordination so that the cylindrical slider moves with the coordinating link.

[0021] The shoulder fitting frame is fine-tuned using pneumatic muscles #1, #2, and #3 as follows: The displacement of the shoulder fitting frame is represented by the displacement of the connection point between pneumatic muscle #3 and the L-shaped rod. A coordinate system is established with the connection point between pneumatic muscle #1 and link #1 as the origin A. Let point B be the connection point between pneumatic muscle #1 and link #3, point C be the connection point between pneumatic muscle #2 and link #3, point D be the connection point between link #2 and link #1, point E be the connection point between link #1 and link #2, point F be the connection point between link #2 and pneumatic muscle #3, point G be the connection point between pneumatic muscle #3 and link #4, and point H be the connection point between link #4 and link #3. Point A is defined as the origin. All eight points are located in the same plane coordinate system AXY, with point B located on one side of the positive Y-axis and point D located on one side of the positive X-axis. The x-coordinate of point A is... The ordinate of point A is The x-coordinate of point B is The ordinate of point B is The x-coordinate of point C is The ordinate of point C is The x-coordinate of point D is The ordinate of point D is The x-coordinate of point E is The ordinate of point E is The x-coordinate of point F is The ordinate of point F is The x-coordinate of point G is The ordinate of point G is The x-coordinate of point H is The ordinate of point H is ; , , , , , , , , , , , , The lengths are constant and all are known quantities. and Adjusting using angle adjusters #1 and #2, which are also known quantities, with E being the midpoint of AD and H being the midpoint of BC, it is known that the position of point G needs to be adjusted to the coordinate point... ,definition The length of the variable is obtained. , This allows us to obtain the corresponding elongation of pneumatic muscles No. 1, No. 2, and No. 3; where the coordinates of point A are... The coordinates of point B The coordinates of point D The coordinates of point E ;

[0022] Coordinates of point F In the formula Let EF be the angle between vector EF and the X-axis, and let AD be the angle between vector AD and the positive Y-axis direction. Therefore, the angle between AD and the positive X-axis is... ; ,have to:

[0023] ;

[0024] ;

[0025] ;

[0026] Length of FG ;

[0027] The position of point H is locked by two constraints, which can be solved using the "intersection of two circles"; the first constraint comes from point G, where GH is a fixed-length rod, and H must lie within a circle centered at G with a radius of... On the circle; constraint two comes from point B, H is the midpoint of BC, BC is a fixed-length rod, so the distance from H to B is always . That is, H lies in a circle with B as the center and radius as... On the circle;

[0028] Solve for the coordinates of H by solving the following circle equations simultaneously. ;

[0029] (I)

[0030] (II)

[0031] Subtracting the equations of the two circles yields the equation of the root axis. Expanding the equation:

[0032] ;

[0033] ;

[0034] Subtracting the two equations, we get:

[0035] ;

[0036] tidy about The function expression:

[0037] ;

[0038] Let the constant term ,but:

[0039] (III)

[0040] Substituting expression III back into expression II, we get the following: The quadratic equation of :

[0041] ;

[0042] Both sides ride together Eliminate the denominators and rearrange the equation into the standard quadratic form:

[0043] ;

[0044] Solve using the quadratic formula :

[0045] ;

[0046] In the actual solution, two results were obtained. The maximum value is taken as the final solution;

[0047] pass get:

[0048] ;

[0049] Since H is the midpoint of BC, the coordinates of point C can be obtained using the following formula:

[0050] ;

[0051] ;

[0052] CD length:

[0053] .

[0054] Compared with the prior art, the present invention has the following advantages:

[0055] This invention enables a wide range of complex movements with multiple degrees of freedom, improving the effectiveness of assistance. It can cover upper arm internal / external rotation, upper arm swing, upper arm abduction, and shoulder adjustment movements. Moreover, the range of motion breaks through the spatial limitations of traditional devices, simulating complex trajectories in daily human activities, effectively assisting users, and solving the problem that existing devices are unable to achieve a wide range of complex movements.

[0056] This invention enables coordinated linkage of the left and right joints, enhancing bilateral coordination. The back adjustment mechanism of this invention uses a cylindrical slider as the center of symmetry, and symmetrically sets up linkage mechanisms with pneumatic muscles No. 1, No. 2 and No. 3 as the driving bodies on the left and right sides of the cylindrical slider. Combined with the coordinated linkage, the linkage mechanisms on the left and right sides are linked and controlled, accurately simulating the coordinated relationship of the left and right joints in the natural human activity. This solves the problem of existing single-arm or independent drive devices being out of touch with real life scenarios, and improves the assistive effect.

[0057] This invention uses pneumatic drive to improve the safety of human-computer interaction and the stability of equipment. The invention uses pneumatic muscles as driving elements, which have better compliance than traditional electric drive and can buffer the impact force during movement. At the same time, it avoids electromagnetic interference, can be adapted to user scenarios that require precision monitoring equipment, and the pneumatic components have a low failure rate and are easy to maintain, solving the problems of electromagnetic interference, frequent failures and high maintenance costs of electric equipment.

[0058] Optimized structural adaptability and motion coordination reduce energy consumption and injury risk. The adjustable settings of the outer and inner upper arm bars form a length compensation mechanism, which can accurately adapt to the differences in limb length among different users, ensuring that the upper arm mechanism matches the human arm length. The rotational connection between the arc-shaped and square connectors forms a spatial position compensation mechanism. Through the adaptive adjustment of the arc-shaped connectors, spatial deviations during movement are corrected in real time, so that the motion axis of the upper arm swinging back and forth dynamically coincides with the instantaneous motion axis of the human shoulder joint, reducing additional torque and extra energy consumption, and significantly reducing the risk of tissue damage.

[0059] In this invention, the first, second, third, and fourth connecting rods are all curved rods. Their bending characteristics can cleverly avoid spatial interference in complex structures and complete the force and motion transmission of "non-linear paths" within a limited space. In terms of force distribution, the bending configuration of the curved rod can improve the stress state of the component by dispersing stress concentration. When subjected to alternating loads or impact loads, the arc transition of the bending section can uniformly transmit the concentrated force along the rod body, avoiding the risk of fracture of straight connecting rods due to excessive local stress under sudden loads. Attached Figure Description

[0060] Figure 1 This is a front view of the present invention;

[0061] Figure 2 This is a front view of the back adjustment mechanism of the present invention;

[0062] Figure 3 This is a side view of the present invention;

[0063] Figure 4 This is a rear view of the back adjustment mechanism of the present invention;

[0064] Figure 5 This is a schematic diagram of the drive mechanism of the back adjustment mechanism of the present invention;

[0065] Figure 6 This is a schematic diagram showing the connection of the connecting block, guide rod, and mounting plate of the present invention;

[0066] Figure 7 This is a schematic diagram of the shoulder mechanism of the present invention;

[0067] Figure 8 This is a schematic diagram showing the connection between the upper arm mechanism and the shoulder mechanism of the present invention;

[0068] Figure 9 For the present invention Figure 8 A magnified view of a portion of circle A in the center;

[0069] Figure 10 This is a schematic diagram showing the connection of the capping ring, functional ring, connecting ring, and base ring of the present invention;

[0070] Figure 11 This is a schematic diagram showing the connection between the functional ring and the connecting ring of the present invention;

[0071] Figure 12 This is a simplified diagram of the drive mechanism for the back adjustment of the present invention;

[0072] In the diagram, the components are: back adjustment mechanism 1, shoulder mechanism 2, upper arm mechanism 3, back fixing plate 101, back fixing frame 102, fixing strap 103, mounting plate 104, pneumatic muscle #1 105, angle adjuster #1 106, connecting rod #1 107, pneumatic muscle #2 108, angle adjuster #2 109, connecting rod #2 110, pneumatic muscle #3 111, connecting rod #3 112, connecting rod #4 113, L-shaped rod 114, coordinating connecting rod 115, slide groove 116, cylindrical slider 117, connecting block 118, pneumatic muscle #4 119, guide rod 120, traction rope #1 121, pneumatic muscle #5 122, ball joint 123, guide groove 124, shoulder fitting frame 201, and connecting strap 20. 2. Square connector 203, outer lower guide wheel 204, inner lower guide wheel 205, inner upper guide wheel 206, outer upper guide wheel 207, No. 2 traction rope 208, guide wheel 209, abduction pneumatic muscle 210, spherical connector 211, spring 212, arc connector 213, muscle fixing seat 301, upper arm outer rod 302, upper arm inner rod 303, upper arm fitting frame 304, upper arm strap 305, functional ring 306, connecting ring 307, receiving groove 308, fixing column 309, annular guide ring 310, sealing ring 311, base ring 312, annular guide groove 313, outlet reversing wheel 314, right angle reversing component 315, rotating pneumatic muscle 316, No. 3 traction rope 317, swing arm pneumatic muscle 318. Detailed Implementation

[0073] To further illustrate the technical solution of the present invention, the present invention will be further described below through embodiments.

[0074] like Figures 1 to 12As shown, a multimodal joint-assisted exoskeleton robot includes a back adjustment mechanism 1. The back adjustment mechanism 1 includes a back fixation plate 101, a back fixation frame 102 is provided on the upper end surface of the back fixation plate 101, and fixing straps 103 are provided on both the back fixation plate 101 and the back fixation frame 102. Adjacent fixing straps 103 are fixedly connected by buckles. A mounting plate 104 is connected to the rear side of the back fixation plate 101 through multiple ball joints 123 to achieve adaptive adjustment of the posture of the mounting plate 104. A first pneumatic muscle 105 is symmetrically fixed on the left and right sides of the lower part of the mounting plate 104. The first pneumatic muscle 105 is vertically arranged. The lower end of meat 105 is connected to a first connecting rod 107 via a first angle adjuster 106. A second pneumatic muscle 108 is hinged to the other end of the first connecting rod 107. A second connecting rod 110 is connected to the middle of the first connecting rod 107 via a second angle adjuster 109. A third pneumatic muscle 111 is hinged to the other end of the second connecting rod 110. A third connecting rod 112 is hinged to the upper end of the second pneumatic muscle 108. The other end of the third connecting rod 112 is hinged to the upper end of the first pneumatic muscle 105. A fourth connecting rod 113 is hinged to the middle of the third connecting rod 112. The other end of the fourth connecting rod 113 is hinged to the upper end of the third pneumatic muscle 111. The upper end is fixedly connected to the lower end of the L-shaped rod 114. A coordinating link 115 is hinged between the upper ends of the two second pneumatic muscles 108 on the left and right sides. The coordinating link 115 includes a telescopic outer rod and a telescopic inner rod. The telescopic inner rod is slidably disposed inside the telescopic outer rod. A groove 116 is provided on the telescopic outer rod. A cylindrical slider 117 is slidably disposed within the groove 116. A guide rod 120 is fixedly connected to the cylindrical slider 117. The guide rod 120 is slidably disposed within a guide groove 124 on the mounting plate 104. A connecting block 118 is fixedly disposed on the upper part of the guide rod 120. The lower end of the connecting block 118 is fixedly connected to the upper end of the fourth pneumatic muscle 119. The lower end of the No. 4 pneumatic muscle 119 is fixedly connected to the mounting plate 104. The upper end of the connecting block 118 is fixedly connected to the No. 1 traction rope 121. The other end of the No. 1 traction rope 121 passes around the upper end of the back fixation frame 102 and connects to the upper end of the No. 5 pneumatic muscle 122. The lower end of the No. 5 pneumatic muscle 122 is installed on the back fixation plate 101. A shoulder mechanism 2 is installed on the upper end of the L-shaped rod 114. A large arm mechanism 3 is installed on the outside of the shoulder mechanism 2. The No. 1 connecting rod 107, the No. 2 connecting rod 110, the No. 3 connecting rod 112 and the No. 4 connecting rod 113 are all curved rods to prevent mutual interference between the No. 1 connecting rod 107, the No. 2 connecting rod 110, the No. 3 connecting rod 112 and the No. 4 connecting rod 113.

[0075] The shoulder mechanism 2 includes a shoulder fitting frame 201. A connecting strap 202 is provided below the shoulder fitting frame 201 to fix the shoulder fitting frame 201 to the human shoulder. A square connector 203 is rotatably connected to the front end of the shoulder fitting frame 201. An outer lower guide wheel 204, an inner lower guide wheel 205, an inner upper guide wheel 206, and an outer upper guide wheel 207 are respectively provided at the four corners of the front end face of the square connector 203. A second traction rope 208 is fixedly provided on the outer lower guide wheel 204. The other end of the second traction rope 208 passes sequentially around the inner lower guide wheel 205, the inner upper guide wheel 206, and the outer upper guide wheel 207. The upper guide wheel 207, multiple thread guide wheels 209, and the upper part of the back fixation frame 102 are fixedly connected to the upper end of the abduction pneumatic muscle 210. The lower end of the abduction pneumatic muscle 210 is mounted on the back fixation plate 101. Multiple thread guide wheels 209 are respectively mounted on the upper surface of the shoulder fitting frame 201. A spring 212 is provided between the outer end of the square connector 203 and the shoulder fitting frame 201. An arc-shaped connector 213 is rotatably connected to the outer end of the square connector 203. A spherical connector 211 is fixedly installed on the outer end of the arc-shaped connector 213. A large arm mechanism 3 is mounted on the spherical connector 211.

[0076] The upper arm mechanism 3 includes a muscle fixation seat 301, which is hinged to the upper end of a spherical connector 211. An outer upper arm rod 302 is hinged to the outside of the spherical connector 211, and an inner upper arm rod 303 is slidably disposed inside the outer upper arm rod 302. The outer upper arm rod 302 and the inner upper arm rod 303 are fixedly connected by bolts. An upper arm fitting frame 304 is fixedly disposed on the inner side of the upper part of the inner upper arm rod 303, and an upper arm strap 305 is disposed on the upper arm fitting frame 304. A functional ring 306 is fixedly connected to the outer side of the upper part. Simultaneously, the functional ring 306 is fixedly connected to the upper surface of the connecting ring 307. A receiving groove 308 is formed on the functional ring 306, and fixing posts 309 are provided at both ends of the receiving groove 308. The fixing posts 309 are fixedly connected to the functional ring 306. Annular guide rings 310 are provided on both the upper and lower surfaces of the connecting ring 307. The upper annular guide ring 310 has a notch for the passage of the No. 3 traction rope 317. Above the connecting ring 307... A cover ring 311 and a base ring 312 are respectively provided below and below. Both the cover ring 311 and the base ring 312 have annular guide grooves 313 corresponding to the annular guide ring 310. Two outlet reversing wheels 314 and right-angle reversing elements 315 are provided on the base ring 312, with the two outlet reversing wheels 314 located between the two right-angle reversing elements 315. A notch is provided on the cover ring 311 to allow space for the outlet reversing wheels 314 and the right-angle reversing elements 315. Above the right-angle reversing elements 315 is a... A rotating pneumatic muscle 316 is provided, the upper end of which is connected to a muscle fixing seat 301 via a Hooke hinge. The lower end of the rotating pneumatic muscle 316 is fixedly connected to a No. 3 traction rope 317. The No. 3 traction rope 317 is connected to a corresponding fixing post 309 after passing through a corresponding right-angle reversing member 315 and an outlet reversing wheel 314. A swing arm pneumatic muscle 318 is connected to both the front and rear sides of the muscle fixing seat 301 via a Hooke hinge. The lower end of the swing arm pneumatic muscle 318 is connected to a sealing ring 311 via a Hooke hinge.

[0077] A method of using a multimodal joint-assisted exoskeleton robot includes upper arm internal / external rotation, upper arm swinging, upper arm abduction, and shoulder adjustment movements;

[0078] Upper arm internal / external rotation movement: The upper arm inner bar 303 is fixed to the human upper arm through the upper arm fitting frame 304 and the upper arm strap 305. One of the rotating pneumatic muscles 316 shortens, driving the corresponding No. 3 traction rope 317 to rise, thereby pulling the functional ring 306 and the connecting ring 307 to rotate. The other rotating pneumatic muscle 316 extends, lowering the No. 3 traction rope 317 connected to it, so as to realize the coordination of the rotation of the functional ring 306 and the connecting ring 307. The rotation of the functional ring 306 and the connecting ring 307 drives the upper arm to perform internal / external rotation movement.

[0079] Upper arm swinging movement: When the front arm swinging pneumatic muscle 318 shortens and the rear arm swinging pneumatic muscle 318 lengthens, the upper arm swings forward; conversely, when the front arm swinging pneumatic muscle 318 lengthens and the rear arm swinging pneumatic muscle 318 shortens, the upper arm swings backward.

[0080] Upper arm abduction movement: When the abduction pneumatic muscle 210 shortens, it pulls the second traction rope 208. The second traction rope 208 drives the square connector 203 to rotate. Since the other end of the square connector 203 is connected to the upper arm mechanism 3 through the arc connector 213 and the ball connector 211, it ultimately drives the upper arm mechanism 3 and the human upper arm to achieve abduction movement. When the upper arm does not need to be abducted, the abduction pneumatic muscle 210 extends, and the upper arm mechanism 3 and the human upper arm fall under their own weight and the action of the spring 212.

[0081] Shoulder adjustment exercise: When the position of the shoulder fitting frame 201 needs to be adjusted according to the body size, the angle between the first pneumatic muscle 105 and the first connecting rod 107 is adjusted by the first angle adjuster 106, and the angle between the first connecting rod 107 and the second connecting rod 110 is adjusted by the second angle adjuster 109, thereby achieving the initial adjustment of the position of the shoulder fitting frame 201. Afterwards, the first pneumatic muscle 105, the second pneumatic muscle 108, and the third pneumatic muscle on both sides are adjusted. The coordinated movement of muscle 111 enables fine-tuning of the position of the shoulder fitting frame 201 on both sides. Simultaneously, pneumatic muscles 119 (number four) and 122 (number five) move accordingly to adapt to the adjustment of the shoulder fitting frame 201 position. During operation, when the left and right shoulders of the body need to move coordinatedly (one side raising, one side lowering), the coordination of pneumatic muscles 119 and 122 ensures that the height of the cylindrical slider 117 remains constant. This is achieved by adjusting the position of the first pneumatic muscle on one side. The lengths of pneumatic muscles 105, 108, and 111 elevate the shoulder on that side. Due to the limiting effect of the cylindrical slider 117 on the coordinating link 115, the other side of the coordinating link 115 descends under the lever principle. Simultaneously, pneumatic muscles 105, 108, and 111 on the other side move in sync, causing the shoulder on that side to descend, completing the coordinated movement of both shoulders. During operation, when only... When one shoulder is to move, the first pneumatic muscle 105, the second pneumatic muscle 108, and the third pneumatic muscle 111 on that side change their lengths to drive the shoulder movement. At the same time, the movement of the second pneumatic muscle 108 will drive the coordinating link 115 to move. In order to ensure that the position of the other end of the coordinating link 115 does not change, the fourth pneumatic muscle 119 and the fifth pneumatic muscle 122 need to move in coordination so that the cylindrical slider 117 moves with the coordinating link 115.

[0082] The shoulder fitting frame 201 is finely adjusted using pneumatic muscle 105, pneumatic muscle 108, and pneumatic muscle 111. Specifically, the displacement of the shoulder fitting frame 201 is represented by the displacement of the connection point between pneumatic muscle 111 and L-shaped rod 114. A coordinate system is established with the connection point between pneumatic muscle 105 and connecting rod 107 as the origin A. Point B is the connection point between pneumatic muscle 105 and connecting rod 112, and point C is the connection point between pneumatic muscle 108 and connecting rod 112. Point D is the connection point between meat 108 and link 107; point E is the connection point between link 107 and link 110; point F is the connection point between link 110 and pneumatic muscle 111; point G is the connection point between pneumatic muscle 111 and link 113; and point H is the connection point between link 113 and link 112. Point A is defined as the origin. All eight points are located in the same plane coordinate system AXY. Point B is located on one side of the positive Y-axis, and point D is located on one side of the positive X-axis. The x-coordinate of point A is... The ordinate of point A is The x-coordinate of point B is The ordinate of point B is The x-coordinate of point C is The ordinate of point C is The x-coordinate of point D is The ordinate of point D is The x-coordinate of point E is The ordinate of point E is The x-coordinate of point F is The ordinate of point F is The x-coordinate of point G is The ordinate of point G is The x-coordinate of point H is The ordinate of point H is ; , , , , , , , , , , , , The lengths are constant and all are known quantities. and Adjusting using angle adjuster 106 and angle adjuster 109 (also known quantities), where E is the midpoint of AD and H is the midpoint of BC, the desired position of point G needs to be adjusted to the coordinate point... ,definition The length of the variable is obtained. , This allows us to obtain the corresponding elongation of pneumatic muscle 105, pneumatic muscle 108, and pneumatic muscle 111; where the coordinates of point A are... The coordinates of point B The coordinates of point D The coordinates of point E ;

[0083] Coordinates of point F In the formula Let EF be the angle between vector EF and the X-axis, and let AD be the angle between vector AD and the positive Y-axis direction. Therefore, the angle between AD and the positive X-axis is... ; ,have to:

[0084] ;

[0085] ;

[0086] ;

[0087] Length of FG ;

[0088] The position of point H is locked by two constraints, which can be solved using the "intersection of two circles"; the first constraint comes from point G, where GH is a fixed-length rod, and H must lie within a circle centered at G with a radius of... On the circle; constraint two comes from point B, H is the midpoint of BC, BC is a fixed-length rod, so the distance from H to B is always . That is, H lies in a circle with B as the center and radius as... On the circle;

[0089] Solve for the coordinates of H by solving the following circle equations simultaneously. ;

[0090] (I)

[0091] (II)

[0092] Subtracting the equations of the two circles yields the equation of the root axis. Expanding the equation:

[0093] ;

[0094] ;

[0095] Subtracting the two equations, we get:

[0096] ;

[0097] tidy about The function expression:

[0098] ;

[0099] Let the constant term ,but:

[0100] (III)

[0101] Substituting expression III back into expression II, we get the following: The quadratic equation of :

[0102] ;

[0103] Both sides ride together Eliminate the denominators and rearrange the equation into the standard quadratic form:

[0104] ;

[0105] Solve using the quadratic formula :

[0106] ;

[0107] In the actual solution, two results were obtained. The maximum value is taken as the final solution;

[0108] pass get:

[0109] ;

[0110] Since H is the midpoint of BC, the coordinates of point C can be obtained using the following formula:

[0111] ;

[0112] ;

[0113] CD length:

[0114] .

[0115] The foregoing has shown and described the main features and advantages of the present invention. It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0116] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A multimodal joint-assisted exoskeleton robot, characterized in that: The system includes a back adjustment mechanism (1), which includes a back fixing plate (101). A back fixing frame (102) is provided on the upper surface of the back fixing plate (101). Fixing straps (103) are provided on both the back fixing plate (101) and the back fixing frame (102). Adjacent fixing straps (103) are fixedly connected by buckles. An installation plate (104) is provided on the rear side of the back fixing plate (101). A first pneumatic muscle (105) is symmetrically fixed on the left and right sides of the lower part of the installation plate (104). The first pneumatic muscle (105) is vertically arranged. An angle adjuster (105) is used at the lower end of the first pneumatic muscle (105). 106) Connected to a first link (107), a second pneumatic muscle (108) is hinged to the other end of the first link (107), a second link (110) is connected to the middle of the first link (107) via a second angle adjuster (109), a third pneumatic muscle (111) is hinged to the other end of the second link (110), a third link (112) is hinged to the upper end of the second pneumatic muscle (108), the other end of the third link (112) is hinged to the upper end of the first pneumatic muscle (105), a fourth link (113) is hinged to the middle of the third link (112), and the other end of the fourth link (113) is connected to the third pneumatic muscle (111). The upper end is hinged, and the upper end of the third pneumatic muscle (111) is fixedly connected to the lower end of the L-shaped rod (114). A coordinating link (115) is hinged between the upper ends of the two second pneumatic muscles (108) on the left and right sides. The coordinating link (115) includes a telescopic outer rod and a telescopic inner rod. The telescopic inner rod is slidably disposed inside the telescopic outer rod. A groove (116) is provided on the telescopic outer rod. A cylindrical slider (117) is slidably disposed in the groove (116). A guide rod (120) is fixedly connected to the cylindrical slider (117). The guide rod (120) is slidably disposed in the guide groove (124) on the mounting plate (104). A connecting block (118) is fixedly installed on the upper part of the L-shaped rod (114). The lower end of the connecting block (118) is fixedly connected to the upper end of the fourth pneumatic muscle (119). The lower end of the fourth pneumatic muscle (119) is fixedly connected to the mounting plate (104). The upper end of the connecting block (118) is fixedly connected to the first traction rope (121). The other end of the first traction rope (121) passes around the upper end of the back fixation frame (102) and is connected to the upper end of the fifth pneumatic muscle (122). The lower end of the fifth pneumatic muscle (122) is installed on the back fixation plate (101). A shoulder mechanism (2) is installed on the upper end of the L-shaped rod (114). A large arm mechanism (3) is installed on the outside of the shoulder mechanism (2). The shoulder mechanism (2) includes a shoulder fitting frame (201). A connecting strap (202) is provided below the shoulder fitting frame (201) to fix the shoulder fitting frame (201) to the human shoulder. A square connector (203) is rotatably connected to the front end of the shoulder fitting frame (201). An outer lower guide wheel (204), an inner lower guide wheel (205), an inner upper guide wheel (206), and an outer upper guide wheel (207) are respectively provided on the four corners of the front end face of the square connector (203). A second traction rope (208) is fixedly provided on the outer lower guide wheel (204). The other end of the second traction rope (208) passes around the inner lower guide wheel in sequence. The upper part of the guide wheel (205), the inner upper guide wheel (206), the outer upper guide wheel (207), multiple thread guide wheels (209), and the back fixing frame (102) are fixedly connected to the upper end of the abduction pneumatic muscle (210). The lower end of the abduction pneumatic muscle (210) is mounted on the back fixing plate (101). Multiple thread guide wheels (209) are respectively mounted on the upper surface of the shoulder fitting frame (201). An arc-shaped connector (213) is rotatably connected to the outer end of the square connector (203). A spherical connector (211) is fixedly installed on the outer end of the arc-shaped connector (213). A large arm mechanism (3) is installed on the spherical connector (211).

2. The multimodal joint-assisted exoskeleton robot according to claim 1, characterized in that: The upper arm mechanism (3) includes a muscle fixation seat (301), which is hinged to the upper end of a spherical connector (211). An outer upper arm rod (302) is hinged to the outside of the spherical connector (211), and an inner upper arm rod (303) is slidably disposed inside the outer upper arm rod (302). The outer upper arm rod (302) and the inner upper arm rod (303) are fixedly connected by bolts. An upper arm fitting frame (304) is fixedly disposed on the inner side of the upper part of the inner upper arm rod (303), and an upper arm strap (305) is disposed on the upper arm fitting frame (304). The inner upper arm rod (303) is fixedly disposed on the inner side of the upper part of the inner upper arm rod (303). 3) A functional ring (306) is fixedly connected to the outer side of the upper part. At the same time, the functional ring (306) is fixedly connected to the upper surface of the connecting ring (307). A receiving groove (308) is provided on the functional ring (306). Fixed posts (309) are provided at both ends of the receiving groove (308). The fixed posts (309) are fixedly connected to the functional ring (306). Annular guide rings (310) are provided on both the upper and lower surfaces of the connecting ring (307). An opening for the No. 3 traction rope (317) to pass through is provided on the upper surface of the connecting ring (307). A cover ring (311) and a base ring (312) are respectively provided on the top and bottom sides. Both the cover ring (311) and the base ring (312) have annular guide grooves (313) corresponding to the annular guide ring (310). Two outlet reversing wheels (314) and a right-angle reversing element (315) are provided on the base ring (312), with the two outlet reversing wheels (314) located between the two right-angle reversing elements (315). A notch is provided on the cover ring (311) to make way for the outlet reversing wheels (314) and the right-angle reversing element (315). Above the right-angle reversing element (315)... A rotating pneumatic muscle (316) is provided. The upper end of the rotating pneumatic muscle (316) is connected to the muscle fixing seat (301) via a Hooke hinge. The lower end of the rotating pneumatic muscle (316) is fixedly connected to a No. 3 traction rope (317). The No. 3 traction rope (317) is connected to the corresponding fixing column (309) after passing through the corresponding right-angle reversing member (315) and the outlet reversing wheel (314). A swing arm pneumatic muscle (318) is connected to the front and rear sides of the muscle fixing seat (301) via a Hooke hinge. The lower end of the swing arm pneumatic muscle (318) is connected to the sealing ring (311) via a Hooke hinge.

3. The multimodal joint-assisted exoskeleton robot according to claim 1, characterized in that: The first link (107), the second link (110), the third link (112), and the fourth link (113) are all curved links to prevent mutual interference between them.

4. The multimodal joint-assisted exoskeleton robot according to claim 1, characterized in that: The mounting plate (104) is connected to the back fixing plate (101) through multiple ball joints (123) to achieve adaptive adjustment of the posture of the mounting plate (104).

5. A multimodal joint-assisted exoskeleton robot according to claim 2, characterized in that: A spring (212) is provided between the outer end of the square connector (203) and the shoulder fitting frame (201).

6. A method of using a multimodal joint-assisted exoskeleton robot, based on the multimodal joint-assisted exoskeleton robot of claim 5, characterized in that: This includes upper arm internal / external rotation, upper arm swing, upper arm abduction, and shoulder adjustment movements. Upper arm internal / external rotation movement: The upper arm inner bar (303) is fixed to the human upper arm through the upper arm fitting frame (304) and the upper arm strap (305). One of the rotating pneumatic muscles (316) shortens, driving the corresponding No. 3 traction rope (317) to rise, thereby pulling the functional ring (306) and the connecting ring (307) to rotate. The other rotating pneumatic muscle (316) extends, lowering the No. 3 traction rope (317) connected to it, so as to achieve the coordination of the rotation of the functional ring (306) and the connecting ring (307). The rotation of the functional ring (306) and the connecting ring (307) drives the upper arm to perform internal / external rotation movement. Upper arm swinging motion: When the front arm swinging pneumatic muscle (318) shortens and the rear arm swinging pneumatic muscle (318) lengthens, the upper arm swings forward; conversely, when the front arm swinging pneumatic muscle (318) lengthens and the rear arm swinging pneumatic muscle (318) shortens, the upper arm swings backward. Upper arm abduction movement: When the abduction pneumatic muscle (210) shortens, it pulls the second traction rope (208) to rotate. The second traction rope (208) drives the square connector (203) to rotate. Since the other end of the square connector (203) is connected to the upper arm mechanism (3) through the arc connector (213) and the ball connector (211), it ultimately drives the upper arm mechanism (3) and the human upper arm to achieve abduction movement. When the upper arm does not need to be abducted, the abduction pneumatic muscle (210) extends, and the upper arm mechanism (3) and the human upper arm fall under their own weight and the action of the spring (212). Shoulder adjustment exercise: When it is necessary to adjust the position of the shoulder fitting frame (201) according to the body size, the angle between the first pneumatic muscle (105) and the first connecting rod (107) is adjusted by the first angle adjuster (106), and the angle between the first connecting rod (107) and the second connecting rod (110) is adjusted by the second angle adjuster (109), thereby achieving the initial adjustment of the position of the shoulder fitting frame (201). After that, the first pneumatic muscle (105), the second pneumatic muscle (108), and the third pneumatic muscle on the left and right sides are adjusted. The pneumatic muscles (111) work together to fine-tune the position of the shoulder fitting frame (201) on both sides. At the same time, the fourth pneumatic muscle (119) and the fifth pneumatic muscle (122) follow up to adapt to the adjustment of the position of the shoulder fitting frame (201). During the operation, when the left and right shoulders of the human body need to move together, that is, when one side is raised and the other side is lowered, the height of the cylindrical slider (117) is kept constant by the cooperation of the fourth pneumatic muscle (119) and the fifth pneumatic muscle (122). The height of the cylindrical slider (117) is kept constant by adjusting the first pneumatic muscle on one side. The lengths of the first pneumatic muscle (105), the second pneumatic muscle (108), and the third pneumatic muscle (111) cause the shoulder on that side to rise. Due to the limiting effect of the cylindrical slider (117) on the coordinating link (115), under the lever principle, the other side of the coordinating link (115) sinks. At the same time, the first pneumatic muscle (105), the second pneumatic muscle (108), and the third pneumatic muscle (111) on the other side move synchronously, causing the shoulder on that side to sink, completing the coordinated movement of the left and right shoulders. During the work process, when only... When the shoulder on one side moves, the first pneumatic muscle (105), the second pneumatic muscle (108), and the third pneumatic muscle (111) on that side change length and drive the shoulder to move. At the same time, the movement of the second pneumatic muscle (108) will drive the coordinating link (115) to move. In order to ensure that the position of the other end of the coordinating link (115) does not change, the fourth pneumatic muscle (119) and the fifth pneumatic muscle (122) need to move in coordination so that the cylindrical slider (117) moves with the coordinating link (115). The shoulder fitting frame (201) is finely adjusted using pneumatic muscles No. 1 (105), No. 2 (108), and No. 3 (111). Specifically, the displacement of the shoulder fitting frame (201) is represented by the displacement of the connection point between pneumatic muscle No. 3 (111) and L-shaped rod (114). A coordinate system is established with the connection point between pneumatic muscle No. 1 (105) and connecting rod No. 1 (107) as the origin A. The connection point between pneumatic muscle No. 1 (105) and connecting rod No. 3 (112) is set as point B, and the connection point between pneumatic muscle No. 2 (108) and connecting rod No. 3 (112) is set as point C. Point D is the connection point between the pneumatic muscle (108) and link 1 (107). Point E is the connection point between link 1 (107) and link 2 (110). Point F is the connection point between link 2 (110) and pneumatic muscle 3 (111). Point G is the connection point between pneumatic muscle 3 (111) and link 4 (113). Point H is the connection point between link 4 (113) and link 3 (112). Point A is defined as the origin of the coordinate system. The above eight points are located in the same plane coordinate system AXY. Point B is located on one side of the positive Y-axis, and point D is located on one side of the positive X-axis. The x-coordinate of point A is... The ordinate of point A is The x-coordinate of point B is The ordinate of point B is The x-coordinate of point C is The ordinate of point C is The x-coordinate of point D is The ordinate of point D is The x-coordinate of point E is The ordinate of point E is The x-coordinate of point F is The ordinate of point F is The x-coordinate of point G is The ordinate of point G is The x-coordinate of point H is The ordinate of point H is ; , , , , , , , , , , , , The lengths are constant and all are known quantities. and Adjusting using angle adjuster 1 (106) and angle adjuster 2 (109), which are also known quantities, E is the midpoint of AD, H is the midpoint of BC, and it is known that the position of point G needs to be adjusted to the coordinate point. ,definition The length of the variable is obtained. , This yields the corresponding elongation values ​​of pneumatic muscle No. 1 (105), pneumatic muscle No. 2 (108), and pneumatic muscle No. 3 (111); where the coordinates of point A are... The coordinates of point B The coordinates of point D The coordinates of point E ; Coordinates of point F In the formula Let EF be the angle between vector EF and the X-axis, and let AD be the angle between vector AD and the positive Y-axis direction. Therefore, the angle between AD and the positive X-axis is... ; ,have to: ； ； ； Length of FG ; The position of point H is locked by two constraints, which can be solved using the "intersection of two circles"; the first constraint comes from point G, where GH is a fixed-length rod, and H must lie within a circle centered at G with a radius of... On the circle; constraint two comes from point B, H is the midpoint of BC, BC is a fixed-length rod, so the distance from H to B is always . That is, H lies in a circle with B as the center and radius as... On the circle; Solve for the coordinates of H by solving the following circle equations simultaneously. ; (I) (II) Subtracting the equations of the two circles yields the equation of the root axis. Expanding the equation: ； ； Subtracting the two equations, we get: ； tidy about The function expression: ； Let the constant term ,but: (III) Substituting this expression (III) back into expression (II), we obtain the following: The quadratic equation of : ； Both sides ride together Eliminate the denominators and rearrange the equation into the standard quadratic form: ； Solve using the quadratic formula : ； In the actual solution, two results were obtained. The maximum value is taken as the final solution; pass get: ； Since H is the midpoint of BC, the coordinates of point C can be obtained using the following formula: ； ； CD length: 。

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