Lower extremity exoskeleton muscle and tendon synergic storage capacity moment driving device

Abstract

A kind of lower limb exoskeleton muscle and tendon synergic energy storage capacity moment driving device.For solving the problems such as single energy storage mode, passive phase switching and low driving efficiency existing in exoskeleton muscle and tendon synergic energy storage related technologies, a passive module is arranged between the ankle of lower leg exoskeleton and the rear thigh exoskeleton, the passive module includes three passive energy storage ropes, a second spring, a third spring and three fixed pulleys;the energy storage capacity moment driving device is provided with an active module, the active module includes an active box, an active energy storage rope, a motor and a winding wheel;the power output end of the motor is provided with a winding wheel, the left end of the reset rope is slid through a sliding block, then upwardly passes through a second fixed pulley and is fixed on the upper left side of the sliding block.The lower limb exoskeleton transmission shaft and the transmission shaft of the active phase switching device are driven by a synchronous belt.The utility model improves the energy utilization rate of exoskeleton device under different gait phases, and improves the load adaptive adjustment capability.

Description

Technical Field

[0001] This utility model relates to a torque-storing drive device for the coordinated storage of muscles and tendons in the lower limb exoskeleton. Background Technology

[0002] Exoskeleton muscle and tendon synergistic energy storage technologies all focus on gait energy management for lower limb exoskeletons. Their core idea is to borrow the biomimetic logic of "energy storage-release" from biological tendons, using elastic elements such as springs to simulate the elastic characteristics of the Achilles tendon. This allows for the absorption of impact energy during the gait support phase and its release during the swing phase to provide assistance. Simultaneously, mechanical structures such as four-bar linkages are commonly used, dividing the gait into approximately 60% support phase and 40% swing phase based on motion characteristics such as dead points and stroke ratios, achieving temporal control of the energy transfer path. The overall approach primarily relies on passive energy storage, depending on the physical properties of elastic elements to store and release energy. While some solutions incorporate drive components such as servo motors, a highly efficient synergistic mechanism between active drive and passive energy storage has not yet been formed. Limitations exist in energy hierarchical management, active phase control, and drive performance optimization. For example, a single energy storage method cannot adapt to different phase loads, passive phase switching easily leads to overload of drive components, and the lack of deep coupling between the motor and energy storage elements results in low energy utilization efficiency. These shortcomings are addressed in this patent's approach, which utilizes a hybrid energy storage system, an active phase switching mechanism, and a motor- The innovative design of spring-assisted drive provides room for improvement.

[0003] The objective shortcomings of existing technologies are summarized as follows:

[0004] 1) Limited energy storage methods: Most use a single passive spring or elastic element for energy storage, lacking hierarchical management of energy (such as high / low stiffness module coupling), and cannot simultaneously meet the needs of buffer energy storage during the support period and efficient energy release during the swing period; deep synergy between active drive (motor) and passive energy storage is not achieved, the motor is only used as an independent power source or does not participate in the energy storage process, resulting in low energy utilization efficiency.

[0005] 2) Passive phase switching: It relies on mechanical dead points, inertial forces and other passive methods to switch energy paths, and cannot dynamically isolate loads according to gait phase (such as high impact loads during the support period acting directly on the drive components), which poses a risk of motor overload damage.

[0006] 3) Limitations in driving performance: Pure passive energy storage schemes (such as motorless drives) are insufficient in assisting high-intensity movements, while pure active drive schemes (such as direct motor drives) have high energy consumption and lack the ability to recover and utilize impact energy; a complete biomimetic drive chain of "energy storage-amplification-release" has not been formed, and the torque output capability and energy cycle efficiency need to be improved. Summary of the Invention

[0007] The purpose of this invention is to address the problems of single energy storage method, passive phase switching, and low driving efficiency in the related technologies of exoskeleton muscle and tendon collaborative energy storage, and to provide a lower limb exoskeleton muscle and tendon collaborative energy storage torque drive device.

[0008] The above objectives are achieved through the following technical solutions:

[0009] A lower limb exoskeleton muscle and tendon coordinated torque storage drive device comprises a foot support assembly, a torque storage drive device, and a lower limb exoskeleton; the lower limb exoskeleton is connected above the foot support assembly, and the torque storage drive device is disposed above the lower limb exoskeleton.

[0010] The lower limb exoskeleton includes a lower leg exoskeleton and a thigh exoskeleton. The upper part of the lower leg exoskeleton is connected to the thigh exoskeleton. The thigh exoskeleton includes a front thigh exoskeleton and a rear thigh exoskeleton arranged front and rear. The upper end of the front thigh exoskeleton is hinged to the front upper part of the first interlayer of the energy storage torque drive device, and the rear thigh exoskeleton is hinged to the lower limb exoskeleton drive shaft in the second interlayer. The lower limb exoskeleton drive shaft is located at the rear end of the second interlayer.

[0011] A third fixed pulley is installed at the middle of the front end of the second interlayer of the energy storage torque drive device. An active module is installed at the rear end of the second interlayer. The active module includes an active housing, an active energy storage rope, a motor, and a reel. The motor and the reel are located below the rear end of the second interlayer, and the reel is installed at the power output end of the motor. In the active housing, a first fixed pulley, a first spring, a slider, and a second fixed pulley are sequentially arranged from the rear end to the front end of the second interlayer. A reset rope is installed below the first spring. The right side of the slider is connected to the first spring. The other end of the first spring passes through the active energy storage rope, goes around the first fixed pulley, and is connected downward to the reel. The right end of the reset rope goes around the first fixed pulley and is connected downward to the reel. The left end of the reset rope slides through the slider, goes up around the second fixed pulley, and is fixed to the upper left side of the slider. An active phase switching device is installed below the active housing via a drive shaft. An insertion hole is provided on the bottom of the active housing to provide a movement channel for the active phase switching device.

[0012] A passive module is installed between the ankle of the lower leg exoskeleton and the posterior thigh exoskeleton. The passive module includes a first passive energy storage rope, a second passive energy storage rope, a third passive energy storage rope, a second spring, a third spring, and three fixed pulleys. Two fixed pulleys are installed at the top and bottom of the posterior thigh exoskeleton, and one fixed pulley is installed at the ankle of the lower leg exoskeleton. One end of the first passive energy storage rope is fixed to the fixed pulley at the top of the posterior thigh exoskeleton, and the other end is connected downwards to one end of the second spring. The other end of the second spring is connected downwards to one end of the second passive energy storage rope. The other end of the second passive energy storage rope passes around the fixed pulley at the ankle of the lower leg exoskeleton and connects upwards to the lower end of the third spring. The upper end of the third spring is connected to the third passive energy storage rope. The upper end of the third passive energy storage rope passes sequentially around the fixed pulley at the bottom of the posterior thigh exoskeleton, the fixed pulley at the top of the posterior thigh exoskeleton, the third fixed pulley, and the second fixed pulley before connecting to the upper left side of the slider.

[0013] The lower limb exoskeleton drive shaft and the active phase switching device drive shaft are driven by a synchronous belt; gears are also installed on the lower limb exoskeleton drive shaft 7 to drive the active phase switching device to move periodically.

[0014] Furthermore, the active phase switching device includes a four-bar linkage and a four-bar linkage buckle. The four-bar linkage drive shaft is located in the middle of the second interlayer and is vertically arranged on the base panel of the second interlayer. The crank of the four-bar linkage is installed on the drive shaft of the active phase switching device. The four-bar linkage buckle is arranged above the four-bar linkage, and the wedge end of the four-bar linkage buckle is located below the insertion hole.

[0015] The gears mounted on the transmission shaft of the lower limb exoskeleton are used to drive the four-bar linkage of the active phase switching device to rotate periodically, thereby causing the four-bar linkage latch to move up and down. Beneficial effects

[0016] This invention employs a hybrid energy storage system structural design and a graded energy control method. A hybrid energy storage system is formed through the coupling of high and low stiffness springs. An active phase switching device is designed based on the stroke ratio of a four-bar linkage. The quick-return characteristic of the four-bar linkage matches the active phase switching of the gait cycle. An energy circulation mechanism is formed through the collaboration of a motor and a first spring, enabling adaptive stiffness adjustment and torque output during gait phase. This achieves graded management, load isolation, and torque amplification of gait energy in the lower limb exoskeleton, overcoming the limitations of existing single passive energy storage and passive phase switching. It maximizes the energy utilization rate of the exoskeleton device under different gait phases and improves the load adaptive adjustment capability. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0018] Figure 2This is a schematic diagram of the connection between the torque storage drive device and the lower limb exoskeleton of this utility model;

[0019] Figure 3 This is a detailed drawing of the torque storage drive device of this utility model;

[0020] Figure 4 This is a schematic diagram of the structure of the lower limb exoskeleton of this utility model, which is equipped with a passive module (second spring, third spring and passive energy storage rope);

[0021] Figure 5 This is a structural schematic diagram of the passive module (second spring, third spring and passive energy storage rope) of this utility model;

[0022] Figure 6 This is a schematic diagram of the torque storage drive device of this utility model in the support phase state;

[0023] Figure 7 This is a schematic diagram of the torque storage drive device of this utility model in the swing phase state.

[0024] In the diagram, 1 is the foot support assembly; 2 is the first interlayer; 3 is the second interlayer; 4 is the lower leg exoskeleton; 5 is the foret thigh exoskeleton; 6 is the hind thigh exoskeleton; 7 is the lower limb exoskeleton drive shaft; 8 is the third fixed pulley; 9 is the active housing; 10 is the active energy storage rope; 11 is the motor; 12 is the reel; 13 is the first fixed pulley; 14 is the first spring; 15 is the slider; 16 is the second fixed pulley; 17 is the reset rope; 18 is the first passive energy storage rope; 19 is the second passive energy storage rope; 20 is the third passive energy storage rope; 21 is the second spring; 22 is the third spring; 23 is the active phase switching device drive shaft; 24 is the four-bar linkage; 25 is the four-bar linkage buckle; and 26 is the triangular limit block. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model. Specific implementation method one:

[0027] This embodiment provides a lower limb exoskeleton muscle and tendon coordinated torque storage drive device, such as... Figure 1As shown, it comprises a foot support assembly 1, a torque storage drive device, and a lower limb exoskeleton; the lower limb exoskeleton is connected above the foot support assembly 1, and the torque storage drive device is disposed above the lower limb exoskeleton; the torque storage drive device has a first interlayer 2 and a second interlayer 3.

[0028] like Figure 1 and 2 As shown, the lower limb exoskeleton includes a lower leg exoskeleton 4 and a thigh exoskeleton. The thigh exoskeleton is connected to the upper part of the lower leg exoskeleton 4. The thigh exoskeleton includes a front thigh exoskeleton 5 and a rear thigh exoskeleton 6 arranged front to back. The upper end of the front thigh exoskeleton 5 is hinged to the upper front part of the first interlayer 2 of the torque storage drive device. The rear thigh exoskeleton 6 is hinged to the lower limb exoskeleton drive shaft 7 in the second interlayer 3. The lower limb exoskeleton drive shaft 7 is located in the lower middle part of the rear end of the second interlayer 3.

[0029] like Figure 3 As shown, a third fixed pulley 8 is installed at the middle of the front end of the second interlayer 3 of the energy storage torque drive device. An active module is installed at the rear end of the second interlayer 3. The active module includes an active housing 9, an active energy storage rope 10, a motor 11, and a reel 12. The motor 11 and the reel 12 are located below the rear end of the second interlayer 3, and the reel 12 is installed at the power output end of the motor 11. The active housing 9 is located above the rear end of the second interlayer 3, that is, at the end away from the transmission shaft 7 of the lower limb exoskeleton. A first fixed pulley 13, a first spring 14, a slider 15, and a second fixed pulley 16 are sequentially arranged from the rear end to the front end of the second interlayer 3 inside the active housing 9. A reset rope 17 is installed below the first spring 14, and the right side of the slider 15 is connected to... The first spring 14 has its other end connected to the winding wheel 12 after passing over the first fixed pulley 13 via the active energy storage rope 10. The right end of the reset rope 17 passes over the first fixed pulley 13 and is connected to the winding wheel 12. The left end of the reset rope 17 slides through the slider 15, passes over the second fixed pulley 16, and is fixed to the upper left side of the slider 15. An active phase switching device is installed below the active housing 9 via the active phase switching device drive shaft 23. An insertion hole is provided on the bottom of the active housing 9 to provide a movement channel for the active phase switching device. The bottom area of ​​the slider 15 is larger than the area of ​​the insertion hole at the bottom of the active housing 9 to ensure that the slider 15 will not fall out of the insertion hole when sliding left and right.

[0030] like Figure 4As shown, a passive module is installed between the ankle of the lower leg exoskeleton 4 and the posterior thigh exoskeleton 6. The passive module includes a first passive energy storage rope 18, a second passive energy storage rope 19, a third passive energy storage rope 20, a second spring 21, a third spring 22, and three fixed pulleys. Two fixed pulleys are installed on the posterior thigh exoskeleton 6 at the top and bottom, respectively, and one fixed pulley is installed at the ankle of the lower leg exoskeleton 4. One end of the first passive energy storage rope 18 is fixed to the fixed pulley on the upper part of the posterior thigh exoskeleton 6, and the other end is connected downward to the second spring. One end of the second spring 21 is connected downward to one end of the second passive energy storage rope 19. The other end of the second passive energy storage rope 19 passes around the fixed pulley at the ankle of the lower leg exoskeleton 4 and then connects upward to the lower end of the third spring 22. The upper end of the third spring 22 is connected to the third passive energy storage rope 20. The upper end of the third passive energy storage rope 20 passes around the fixed pulley at the lower part of the posterior thigh exoskeleton 6, the fixed pulley at the upper part of the posterior thigh exoskeleton 6, the third fixed pulley 8, and the second fixed pulley 16 in sequence and then connects to the upper part of the left side of the slider 15.

[0031] like Figure 2 As shown, the lower limb exoskeleton drive shaft 7 and the active phase switching device drive shaft 23 are driven by a synchronous belt; gears are also installed on the lower limb exoskeleton drive shaft 7 to drive the active phase switching device to move periodically. Specific Implementation Method Two:

[0033] This embodiment of the lower limb exoskeleton muscle and tendon coordinated torque storage drive device differs from the first embodiment in that the active phase switching device includes a four-bar linkage 24 and a four-bar linkage buckle 25. The active phase switching device drive shaft 23 is located in the middle of the second interlayer 3 and is vertically arranged on the base panel of the second interlayer 3. The crank of the four-bar linkage 24 is installed on the active phase switching device drive shaft 23. The four-bar linkage buckle 25 is arranged above the four-bar linkage 24, and the wedge end of the four-bar linkage buckle 25 is located below the insertion hole.

[0034] The gear installed on the transmission shaft 7 of the lower limb exoskeleton is used to drive the four-bar linkage 24 of the active phase switching device to rotate periodically, thereby causing the four-bar linkage latch 25 to move up and down.

[0035] Working principle:

[0036] like Figure 6 ,like Figure 7 As shown. This utility model discloses a lower limb exoskeleton muscle and tendon coordinated energy storage torque drive device. Its core principle originates from the biomimetic design of the cheetah's Achilles tendon movement mechanism: when a cheetah's foot lands, the Achilles tendon is stretched by body weight and impact force, storing elastic potential energy through elastic protein fibers. When pushing off the ground, the Achilles tendon rebounds and releases the potential energy, coordinating with muscle force to drive the body to leap. This utility model's device transforms this biomechanical characteristic into the energy management logic of a mechanical system.

[0037] When the lower limb exoskeleton robot enters the support phase of its gait, the passive module of the hybrid energy storage spring system, composed of the high-stiffness second spring 21 and third spring 22 of the passive module, is first stretched by the leg extension action, thereby undergoing elastic deformation to absorb the impact of the lower limb landing, achieving mechanical buffering and storing kinetic energy. At the same time, the second and third passive energy storage ropes are also in a stretched state and hold the slider; at this time, the four-bar linkage 24's four-bar linkage buckle 25 is in the uppermost position, and the slider 15 is in the leftmost position; simultaneously, the low-stiffness first spring 14 of the active module, driven by the small-torque motor 11, also slowly accumulates energy through the stretching of the active energy storage rope 10. The low-stiffness characteristic allows the motor 11 to complete long-term energy storage with a small torque. Utilizing the "low power × long time" energy storage characteristic of the small-power motor, the elastic potential energy stored by the first spring 14 is ensured to be converted into a "high torque × short time" output during the swing phase, realizing torque amplification under the drive of the small motor 11. The reset rope 17 is wound with a margin of safety on the reel 12 to ensure that the slider 15 has sufficient length when sliding. At this time, the switching system formed by the four-bar linkage 24 utilizes the quick-return characteristic (stroke speed ratio coefficient 1.5 matches the gait cycle ratio of 60% for the support phase and 40% for the swing phase). Under the combined action of the slider 15, the four-bar linkage buckle 25, and the triangular limit block 26, it can avoid damage to the motor from the high load during the support phase, cut off the energy transmission path between the passive module and the active module, and ensure that the active transmission system is not impacted by the high rigidity load of the passive module.

[0038] When the gait of the lower limb exoskeleton robot enters the swing phase, with the knee of the lower leg exoskeleton 4 as the axis, the lower leg exoskeleton 4 and the foot support component 1 swing upward under the force of the high-rigidity second spring 21 and third spring of the passive module. With the lower limb exoskeleton drive shaft 7 as the axis, the front thigh exoskeleton 5 and the rear thigh exoskeleton 6 swing upward. The gear installed on the lower limb exoskeleton drive shaft 7 drives the four-bar linkage 24 to rotate, causing the four-bar linkage latch 25 to move downward and the slider 15 to move to the right, connecting the passive system and the active system. The four-bar linkage 24 switches to the connected state. Since the first spring 14 is also in a stretched state, the first spring 14 also has elastic potential energy. The forces of the two parts are combined, causing the ground impact energy stored by the second spring 21 and the third spring 22 of the passive module and the energy stored by the active spring module through the motor 11 to be released in synergy. Together with the elastic potential energy of the passive module, they assist the lower limb movement, thus mimicking the "energy storage" of biological tendons. During the "energy release" process, until the gait of the lower limb exoskeleton robot enters the end of the swing phase, the four-bar linkage latch 25 moves to the bottom and the slider 15 reaches the rightmost end.

[0039] Motor 11 begins to reverse, winding up the active energy storage rope 10 and the reset rope 17. The reset rope 17 resets the slider 15 to the left, while the lower leg exoskeleton 4, the foreleg exoskeleton 5, and the hind leg exoskeleton 6 simultaneously swing in the opposite direction to straighten. The four-bar linkage latch 25 then moves upward to its highest point. The system re-enters the support phase state, achieving efficient energy utilization and adaptive load adjustment of the exoskeleton device under different gait phases.

[0040] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A torque-storing drive device for the coordinated storage of muscles and tendons in the lower limb exoskeleton, characterized in that: Its components include a foot support assembly, a torque storage drive device, and a lower limb exoskeleton; the lower limb exoskeleton is connected above the foot support assembly, and the torque storage drive device is installed above the lower limb exoskeleton. The lower limb exoskeleton includes a lower leg exoskeleton and a thigh exoskeleton. The upper part of the lower leg exoskeleton is connected to the thigh exoskeleton. The thigh exoskeleton includes a front thigh exoskeleton and a rear thigh exoskeleton arranged front and rear. The upper end of the front thigh exoskeleton is hinged to the front upper part of the first interlayer of the energy storage torque drive device, and the rear thigh exoskeleton is hinged to the lower limb exoskeleton drive shaft in the second interlayer. The lower limb exoskeleton drive shaft is located at the rear end of the second interlayer. A third fixed pulley is installed at the middle of the front end of the second interlayer of the energy storage torque drive device. An active module is installed at the rear end of the second interlayer. The active module includes an active housing, an active energy storage rope, a motor, and a reel. The motor and the reel are located below the rear end of the second interlayer, and the reel is installed at the power output end of the motor. In the active housing, a first fixed pulley, a first spring, a slider, and a second fixed pulley are sequentially arranged from the rear end to the front end of the second interlayer. A reset rope is installed below the first spring. The right side of the slider is connected to the first spring. The other end of the first spring passes through the active energy storage rope, goes around the first fixed pulley, and is connected downward to the reel. The right end of the reset rope goes around the first fixed pulley and is connected downward to the reel. The left end of the reset rope slides through the slider, goes up around the second fixed pulley, and is fixed to the upper left side of the slider. An active phase switching device is installed below the active housing via a drive shaft. An insertion hole is provided on the bottom of the active housing to provide a movement channel for the active phase switching device. A passive module is installed between the ankle of the lower leg exoskeleton and the posterior thigh exoskeleton. The passive module includes a first passive energy storage rope, a second passive energy storage rope, a third passive energy storage rope, a second spring, a third spring, and three fixed pulleys. Two fixed pulleys are installed on the posterior thigh exoskeleton, one at the ankle of the lower leg exoskeleton. One end of the first passive energy storage rope is fixed to the fixed pulley on the upper part of the posterior thigh exoskeleton, and the other end is connected downwards to one end of the second spring. The other end of the second spring is connected downwards to one end of the second passive energy storage rope. The other end of the second passive energy storage rope passes around the fixed pulley at the ankle of the lower leg exoskeleton and connects upwards to the lower end of the third spring. The upper end of the third spring is connected to the third passive energy storage rope. The upper end of the third passive energy storage rope passes sequentially around the fixed pulleys on the lower part of the posterior thigh exoskeleton, the fixed pulleys on the upper part of the posterior thigh exoskeleton, the third fixed pulley, and the second fixed pulley before connecting to the upper part of the left side of the slider. The lower limb exoskeleton drive shaft and the active phase switching device drive shaft are driven by a synchronous belt; gears are also installed on the lower limb exoskeleton drive shaft to drive the active phase switching device to move periodically.

2. The lower limb exoskeleton muscle and tendon coordinated torque storage drive device according to claim 1, characterized in that: The active phase switching device includes a four-bar linkage and a four-bar linkage buckle. The four-bar linkage drive shaft is located in the middle of the second interlayer and is vertically set on the base panel of the second interlayer. The crank of the four-bar linkage is installed on the drive shaft of the active phase switching device. The four-bar linkage buckle is set above the four-bar linkage, and the wedge end of the four-bar linkage buckle is located below the insertion hole. The gears mounted on the transmission shaft of the lower limb exoskeleton are used to drive the four-bar linkage of the active phase switching device to rotate periodically, thereby causing the four-bar linkage latch to move up and down.

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