Artificial lower limb capable of intelligently adjusting damping based on IMU (Inertial Measurement Unit) and magnetorheological fluid

Abstract

The utility model discloses an artificial lower limb capable of intelligently adjusting damping based on an IMU (Inertial Measurement Unit) and magnetorheological fluid. Comprising a stump mounting sleeve, an artificial thigh part, a knee rotary magnetorheological fluid damper, an artificial shank part, a leg telescopic magnetorheological fluid damper, an ankle rotary magnetorheological fluid damper, an artificial foot part, a foot telescopic magnetorheological fluid damper, an inertia measurement sensor, a first pressure sensor, a second pressure sensor and a damping controller, the stump mounting sleeve is arranged at the upper end of the thigh artificial limb part and used for being connected with a thigh amputation part, and the bottom end of the thigh artificial limb part is rotationally connected with the shank artificial limb part through the knee rotary magnetorheological fluid damper; the bottom end of the lower leg artificial limb part is connected with the artificial foot part through the ankle rotary magnetorheological fluid damper, a gravity center cavity is formed in the gravity center position of the whole artificial lower limb, and the inertia measurement sensor is installed in the gravity center cavity.

Description

A prosthetic lower limb based on IMU and magnetorheological fluid intelligent adjustable damping Technical Field

[0001] This utility model relates to the field of medical supplies technology, specifically to a prosthetic lower limb based on IMU and magnetorheological fluid intelligent adjustable damping. Background Technology

[0002] With the increasing number of patients undergoing lower limb amputations due to traffic accidents, illnesses, and other reasons, various lower limb prostheses are flooding the market. These not only compensate for the shortcomings of limb defects in appearance and function but also allow amputees to freely participate in normal life and work, fulfilling their strong desire to reintegrate into society. As one of the core components of a lower limb prosthesis, the performance of the knee joint directly affects the patient's gait and comfort. Currently, most mainstream prosthetic lower limb designs on the market employ mechanical joints and pneumatic / hydraulic damping systems to simulate and adjust gait. These systems simulate human walking and running movements through pre-set mechanical structures and utilize pneumatic or hydraulic cylinders to adjust joint damping to adapt to different gait requirements.

[0003] However, due to their physical characteristics, traditional pneumatic / hydraulic systems often have response delays, making it difficult to quickly adjust the damping according to the user's intentions, which affects the naturalness and comfort of walking. At the same time, the adjustment method that relies on mechanical structure and preset parameters is difficult to accurately match the needs of individual differences and dynamic changes, resulting in an unrealistic gait simulation. Furthermore, under long-term operation, the energy consumption problem of pneumatic / hydraulic systems is quite prominent, increasing the cost of using prostheses. Summary of the Invention

[0004] The purpose of this invention is to provide a prosthetic lower limb based on IMU and magnetorheological fluid intelligent adjustable damping to solve the above problems.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A prosthetic lower limb based on IMU and magnetorheological fluid intelligent adjustable damping includes a stump mounting sleeve, a thigh prosthesis, a knee rotary magnetorheological fluid damper, a lower leg prosthesis, a leg telescopic magnetorheological fluid damper, an ankle rotary magnetorheological fluid damper, a prosthetic foot, a foot telescopic magnetorheological fluid damper, an inertial measurement sensor, a first pressure sensor, a second pressure sensor, and a damping controller. The stump mounting sleeve is disposed at the upper end of the thigh prosthesis for connecting to the thigh amputation site. The bottom end of the thigh prosthesis is rotatably connected to the lower leg prosthesis via the knee rotary magnetorheological fluid damper. The bottom end of the lower leg prosthesis is connected to the prosthetic foot via the ankle rotary magnetorheological fluid damper. The lower leg prosthesis includes an upper lower leg and a lower lower leg, which are connected by the leg telescopic magnetorheological fluid damper. The prosthetic foot is elastically connected to a magnetorheological fluid damper. It includes an upper foot plate and a lower foot plate arranged vertically. The front ends of the upper and lower foot plates are connected and form an angle. The rear ends of the upper and lower foot plates are elastically connected via a foot-telescopic magnetorheological fluid damper. A center-of-gravity cavity is located at the center of gravity of the entire prosthetic lower limb. An inertial measurement sensor is installed within this cavity. A first pressure sensor is located within the stump mounting sleeve at the connection point to the thigh amputation site. A second pressure sensor is located at the sole of the prosthetic foot. The damping controller is connected to the knee-rotating magnetorheological fluid damper, the leg-telescopic magnetorheological fluid damper, the ankle-rotating magnetorheological fluid damper, the foot-telescopic magnetorheological fluid damper, the inertial measurement sensor, the first pressure sensor, and the second pressure sensor.

[0007] Preferably, both the knee-type rotary magnetorheological fluid damper and the ankle-type rotary magnetorheological fluid damper include a rotary damping cylinder and a damping rotating component that are rotatably connected to each other. The rotary damping cylinder and the damping rotating component are respectively provided with a first rotary joint and a second rotary joint. The first rotary joint is connected to the bottom end of the thigh prosthesis or the bottom end of the lower leg prosthesis through a threaded structure, and the second rotary joint is connected to the top end of the lower leg prosthesis or the upper foot plate through a threaded structure.

[0008] Preferably, both the leg-telescopic magnetorheological fluid damper and the foot-telescopic magnetorheological fluid damper include a telescopic damping cylinder and a damping piston rod. The top of the telescopic damping cylinder has a piston hole for the bottom end of the damping piston rod to be inserted and move up and down. The top of the damping piston rod is provided with a first connecting tube. The bottom of the upper calf or upper foot plate is provided with a first connecting rod inserted into the first connecting tube. The bottom of the telescopic damping cylinder is provided with a second connecting tube. The top of the lower calf or lower foot is provided with a second connecting rod inserted into the second connecting tube.

[0009] Preferably, the first connecting tube has a first bayonet on its wall, the first connecting rod has a first pressing pin that engages with the first bayonet, the second connecting tube has a second bayonet on its wall, and the second connecting rod has a second pressing pin that engages with the second bayonet.

[0010] Preferably, the damping controller is connected to a mobile terminal via a wireless module, and the mobile terminal is a mobile phone or tablet.

[0011] Preferably, the damping controller is a 64-bit MCU microcontroller.

[0012] By adopting the above technical solution, this utility model has the following advantages compared with the prior art:

[0013] This invention provides a prosthetic lower limb based on IMU and magnetorheological fluid intelligent adjustable damping. An inertial measurement sensor is set at the center of gravity of the prosthetic lower limb to collect information on joint angles, angular velocities, and accelerations in real time during movement, accurately capturing the user's movement intentions. A first pressure sensor and a second pressure sensor monitor the magnitude of the ground reaction force received at the leg amputation site and the entire prosthetic lower limb structure during movement. The damping controller dynamically adjusts the current in the electromagnetic coils of different magnetorheological fluid dampers by monitoring the feedback data, thereby controlling the viscosity of the magnetorheological fluid and precisely controlling the damping at each prosthetic connection point to adapt to different road conditions, significantly improving the naturalness and comfort of walking. Attached Figure Description

[0014] Figure 1 is a schematic diagram of the structure of this utility model;

[0015] Figure 2 is a partial enlarged view of the knee-mounted rotary magnetorheological fluid damper or the ankle-mounted rotary magnetorheological fluid damper of this utility model.

[0016] Figure 3 is a partial enlarged view of the leg-telescopic magnetorheological fluid damper or foot-telescopic magnetorheological fluid damper of this utility model. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0018] It should be noted that in this utility model, the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inner", and "outer" are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element of this utility model must have a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0019] Example

[0020] Please refer to Figures 1 to 3. This utility model discloses a prosthetic lower limb based on IMU and magnetorheological fluid intelligent adjustable damping, including a stump mounting sleeve 1, a thigh prosthesis 2, a knee rotary magnetorheological fluid damper 3, a lower leg prosthesis 4, a leg telescopic magnetorheological fluid damper 5, an ankle rotary magnetorheological fluid damper 6, a prosthetic foot 7, a foot telescopic magnetorheological fluid damper 8, an inertial measurement sensor, a first pressure sensor, a second pressure sensor, and a damping controller. The stump mounting sleeve 1 is set at the upper end of the thigh prosthesis 2 to connect to the thigh amputation site. The bottom end of the thigh prosthesis 2 is rotatably connected to the lower leg prosthesis 4 through the knee rotary magnetorheological fluid damper 3. The bottom end of the lower leg prosthesis 4 is connected to the prosthetic foot 7 through the ankle rotary magnetorheological fluid damper 6. The lower leg prosthesis 4 includes an upper lower leg 41 and a lower lower leg 42. The parts 42 are elastically connected by a leg-telescopic magnetorheological fluid damper 5. The prosthetic foot 7 includes an upper foot plate 71 and a lower foot plate 72 arranged vertically. The front ends of the upper foot plate 71 and the lower foot plate 72 are connected and form an angle between them. The rear ends of the upper foot plate 71 and the lower foot plate 72 are elastically connected by a foot-telescopic magnetorheological fluid damper 8. A center of gravity cavity is set at the center of gravity of the entire prosthetic lower limb. An inertial measurement sensor is installed in the center of gravity cavity. A first pressure sensor is set in the stump mounting sleeve 1 at the connection position of the thigh amputation. A second pressure sensor is set at the foot of the prosthetic foot 7. The damping controller is connected to the knee-rotating magnetorheological fluid damper 3, the leg-telescopic magnetorheological fluid damper 5, the ankle-rotating magnetorheological fluid damper 6, the foot-telescopic magnetorheological fluid damper 8, the inertial measurement sensor, the first pressure sensor, and the second pressure sensor.

[0021] Both the knee-type rotary magnetorheological fluid damper 3 and the ankle-type rotary magnetorheological fluid damper 6 include a rotary damping cylinder 31 and a damping rotating component 32 that are rotatably connected to each other. The rotary damping cylinder 31 and the damping rotating component 32 are respectively provided with a first rotary joint 33 and a second rotary joint 34. The first rotary joint 33 is connected to the bottom end of the thigh prosthesis 2 or the bottom end of the lower leg prosthesis 4 through a threaded structure. The second rotary joint 34 is connected to the top end of the lower leg prosthesis 4 or the upper foot plate 72 through a threaded structure.

[0022] The damping rotating component 32 is provided with a rotating rod 35 rotatably inserted into the rotating damping cylinder 31. A first electromagnetic coil 36 is wound around the circumference of the rotating rod 35. By changing the current in the first electromagnetic coil 36, magnetic fields of different intensities are obtained, which changes the flow characteristics of the magnetorheological fluid in the rotating damping cylinder 31, thereby changing the magnitude of the damping force of the rotating magnetorheological fluid damper, which has the functions of shock absorption and pressure regulation.

[0023] Both the leg-type telescopic magnetorheological fluid damper 5 and the foot-type telescopic magnetorheological fluid damper 8 include a telescopic damping cylinder 51 and a damping piston rod 52. The top of the telescopic damping cylinder 51 is provided with a piston hole 511 for the bottom end of the damping piston rod 52 to be inserted and move up and down. The top of the damping piston rod 52 is provided with a first connecting pipe 53. The bottom of the upper lower leg 41 or the upper foot plate 71 is provided with a first connecting rod 54 inserted into the first connecting pipe 53. The bottom of the telescopic damping cylinder 51 is provided with a second connecting pipe 55. The top of the lower lower leg 42 or the lower foot 72 is provided with a second connecting rod 56 inserted into the second connecting pipe 55.

[0024] The first connecting pipe 53 has a first bayonet 531 on its wall, and the first connecting rod 54 has a first pressing pin 541 that is inserted into the first bayonet 531. The second connecting pipe 55 has a second bayonet 551 on its wall, and the second connecting rod 56 has a second pressing pin 561 that is inserted into the second bayonet 551.

[0025] A second electromagnetic coil 57 is circumferentially wound around the damping piston rod 52. The damping piston rod 52 and the second electromagnetic coil 57 reciprocate up and down inside the telescopic damping cylinder 51. A predetermined shear gap is formed between the second electromagnetic coil 57 and the telescopic damping cylinder 51. The magnetic field lines generated by the second electromagnetic coil 57 are perpendicular to the shear gap. The second electromagnetic coil 57 mainly generates a magnetic field. The viscosity of the magnetorheological fluid in the magnetic field changes with the magnetic field strength. During the movement of the damping piston rod 52, the magnetorheological fluid flows through the gap between the inner wall of the telescopic damping cylinder 51 and the damping piston rod 52, thereby changing the magnitude of the damping force of the telescopic magnetorheological fluid damper, which has the functions of shock absorption and pressure regulation.

[0026] The damping controller connects to a mobile terminal, such as a smartphone or tablet, via a wireless module. The damping controller uses a 64-bit MCU microcontroller.

[0027] The above description is merely a preferred embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.

Claims

1. A prosthetic lower limb based on IMU and magnetorheological fluid intelligent adjustable damping, characterized in that: The device includes a stump mounting sleeve, a thigh prosthesis, a knee rotary magnetorheological fluid damper, a lower leg prosthesis, a leg telescopic magnetorheological fluid damper, an ankle rotary magnetorheological fluid damper, a prosthetic foot, a foot telescopic magnetorheological fluid damper, an inertial measurement sensor, a first pressure sensor, a second pressure sensor, and a damping controller. The stump mounting sleeve is located at the upper end of the thigh prosthesis for connecting to the thigh amputation site. The bottom end of the thigh prosthesis is rotatably connected to the lower leg prosthesis via the knee rotary magnetorheological fluid damper. The bottom end of the lower leg prosthesis is connected to the prosthetic foot via the ankle rotary magnetorheological fluid damper. The lower leg prosthesis includes an upper lower leg and a lower lower leg, which are elastically connected by the leg telescopic magnetorheological fluid damper. The prosthetic foot includes an upper foot plate and a lower foot plate arranged vertically. The front ends of the upper foot plate and the lower foot plate are connected and form an included angle. The rear ends of the upper foot plate and the lower foot plate are elastically connected through a foot telescopic magnetorheological fluid damper. A center of gravity cavity is provided at the center of gravity of the entire prosthetic lower limb. The inertial measurement sensor is installed in the center of gravity cavity. The first pressure sensor is located in the stump mounting sleeve at the connection position with the thigh amputation site. The second pressure sensor is located at the sole of the prosthetic foot. The damping controller is connected to the knee rotary magnetorheological fluid damper, the leg telescopic magnetorheological fluid damper, the ankle rotary magnetorheological fluid damper, the foot telescopic magnetorheological fluid damper, the inertial measurement sensor, the first pressure sensor, and the second pressure sensor.

2. The lower extremity prosthesis based on IMU and MR fluid intelligent adjustment damping according to claim 1, characterized in that: Both the knee-type rotary magnetorheological fluid damper and the ankle-type rotary magnetorheological fluid damper include a rotary damping cylinder and a damping rotating component that are rotatably connected to each other. The rotary damping cylinder and the damping rotating component are respectively provided with a first rotary joint and a second rotary joint. The first rotary joint is connected to the bottom end of the thigh prosthesis or the bottom end of the lower leg prosthesis through a threaded structure. The second rotary joint is connected to the top end of the lower leg prosthesis or the upper foot plate through a threaded structure.

3. The lower extremity prosthesis based on IMU and MR fluid intelligent adjusting damping, according to claim 1, characterized in that: Both the leg-type telescopic magnetorheological fluid damper and the foot-type telescopic magnetorheological fluid damper include a telescopic damping cylinder and a damping piston rod. The top of the telescopic damping cylinder has a piston hole for the bottom end of the damping piston rod to be inserted and move up and down. The top of the damping piston rod is provided with a first connecting tube. The bottom of the upper calf or upper foot plate is provided with a first connecting rod inserted into the first connecting tube. The bottom of the telescopic damping cylinder is provided with a second connecting tube. The top of the lower calf or lower foot is provided with a second connecting rod inserted into the second connecting tube.

4. The prosthetic lower limb based on IMU and magnetorheological fluid intelligent adjustable damping as described in claim 3, characterized in that: The first connecting tube has a first bayonet on its wall and the first connecting rod has a first pressing pin that engages with the first bayonet. The second connecting tube has a second bayonet on its wall and the second connecting rod has a second pressing pin that engages with the second bayonet.

5. The prosthetic lower limb based on IMU and magnetorheological fluid intelligent adjustable damping as described in claim 1, characterized in that: The damping controller is connected to a mobile terminal via a wireless module, and the mobile terminal is a mobile phone or tablet.

6. The prosthetic lower limb based on IMU and magnetorheological fluid intelligent adjustable damping as described in claim 1, characterized in that: The damping controller adopts a 64-bit MCU single-chip microcomputer.

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