CN105078701A - Lower limb two-joint rehabilitation training mechanism based on parallel mechanism and two-dimensional force-measuring mechanism - Google Patents

Abstract

The invention discloses a lower limb double-joint rehabilitation training mechanism based on a parallel mechanism and a two-dimensional force-measuring mechanism. It is composed of a short connecting rod, a drive motor, an angle sensor and a rotating shaft; the two-dimensional force measuring mechanism is composed of a pedal and two sets of bridge circuits, wherein the angle sensor is connected to the computer through the amplified interface circuit, and the bridge circuit is connected to the The computer is connected, and the computer is connected with the control circuit of the driving motor. In this way, the computer obtains and processes the measured data of the angle sensor and two groups of bridge circuits through the amplified interface circuit, and obtains the rotation angle information of the short connecting rod, and the vertical position of the foot to the pedal. The active force in the direction and the active force in the forward and backward motion direction, so that the rotation of the driving motor is controlled by the control circuit, and the rehabilitation exercise training of the knee joint and the ankle joint driven by one motor can be realized.

Description

Rehabilitation Training Mechanism for Double Joints of Lower Limbs Based on Parallel Mechanism and Two-dimensional Measuring Mechanism

technical field

The invention belongs to the field of rehabilitation medical equipment, and in particular relates to a rehabilitation training mechanism for double joints of lower limbs which uses a parallel mechanism to realize rehabilitation training for double joints of lower limbs and is equipped with a two-dimensional force measuring mechanism.

Background technique

Rehabilitation robot is a combination of engineering and rehabilitation medicine. It is a typical human-machine integrated system and is the cutting-edge technology in the field of rehabilitation medicine and robotics. The lower limb rehabilitation mechanism is currently a main research object in the field of machinery in the field of rehabilitation medicine. Robot-assisted training, as a rising intelligent rehabilitation technology in the past ten years, has been widely valued by developed countries. Rehabilitation training robots can not only liberate physical therapists from the one-to-one or even many-to-one heavy rehabilitation process of doctors and patients, but also can safely and reliably treat patients with limb motor dysfunction caused by stroke (stroke) and spinal cord injury Adaptive and targeted rehabilitation training, through quantitative exercise and real-time monitoring, can provide patients with a more scientific rehabilitation training model, and put exercise rehabilitation therapy into practice through automatic rehabilitation equipment, which will improve the rehabilitation quality of patients with limb motor dysfunction, It is of great significance to promote the early recovery of patients and reduce the social burden.

Contents of the invention

The technical problem to be solved in the present invention is: in order to provide a safe and effective double-joint rehabilitation training mechanism design for the lower limbs, which can provide rehabilitation trainers with rehabilitation training for the knee joints and ankle joints of the lower limbs at the same time, a method based on a parallel mechanism and The two-dimensional force measuring mechanism is a rehabilitation training mechanism for double joints of the lower limbs.

In order to solve the above-mentioned technical problems, the present invention adopts the following technical scheme: provide a lower limb double-joint rehabilitation training mechanism based on a parallel mechanism and a two-dimensional force measuring mechanism, which is characterized in that the lower limb double-joint rehabilitation training mechanism is composed of a parallel mechanism and a two-dimensional force measuring mechanism. The force mechanism consists of two parts: the parallel mechanism is installed under the seat 1, and is composed of unequal-length parallel links, a short link 2 fixed at one end, a drive motor 4, an angle sensor 3, and rotating shafts 0 and 7. Equal-length parallel links are made up of a rotatable long link 5 and a rotatable short link 6, the output shaft of the driving motor 4 is connected with the rotation axis 0 of the long link 5 near the end of the seat 1, and the angle sensor 3 Set at the junction of two short connecting rods 2 and 6; the two-dimensional force measuring mechanism consists of a pedal and two sets of bridge circuits, the pedal includes a pedal 17, a left support beam 11, a right support beam 12, a front end Fixtures and peripheral parts 16, each group of bridge circuits is composed of 4 strain gauges 14, and the bridge circuit for measuring the vertical force of the feet on the pedals 17 is supported by the left side of the pedals 17 to support the beam 11 It is composed of 4 strain gauges 14 on the four sides of the right side support beam 12, and the bridge circuit for measuring the force of the foot on the front and rear movement direction of the pedal 17 is formed by the left side support beam of the pedal 17. 11 and the right side support beam 12 are composed of 4 strain gauges 14 on the front and rear sides; wherein, the angle sensor 3 is connected to the computer through the interface circuit, and the bridge circuit in the two-dimensional force measuring mechanism is connected to the computer through the interface circuit. connection, the computer is connected to the control circuit of the driving motor 4, the driving motor 4 can drive the long connecting rod 5 in the unequal-length parallel link to rotate, and then drive the movement of the pedal and the rotatable short connecting rod 6 to realize a motor driving the knee joint Rehabilitation exercise training for two joints with the ankle joint, the angle sensor 3 is used to measure the rotation angle of the rotatable short link 6 in the unequal-length parallel link, and the computer obtains and processes the measured data through the interface circuit to control the drive motor The rotation of 4, by comparing with the threshold value, can ensure the safety of the rehabilitation trainer and the safety of the institution.

Optimally, the above-mentioned front-end fixing device and the rear-end fixing device can be elastic fixing devices respectively, the angle sensor 3 is connected to the computer through the bus through the amplifying interface circuit, and the bridge circuit in the two-dimensional force measuring mechanism passes through the amplifying interface circuit It is connected with the computer through a bus, and the front and rear ends of the pedal are respectively provided with a front floating beam 9 and a rear floating beam 15 to secure the pedal.

In addition, the specific steps of the method for using the lower limb double-joint rehabilitation training mechanism based on the parallel mechanism and the two-dimensional force-measuring mechanism in the present invention are as follows:

Step 1: Preset the threshold by computer before use , the threshold angle , are the pressure thresholds in the four directions of the foot to the pedal 17, in unit N, are respectively the forward and backward rotation angle thresholds of the rotatable short connecting rod 6, unit: degree;

Step 2: The rehabilitation trainer sits on the seat 1 and uses the front elastic fixing device 10 and the rear elastic fixing device 13 on the pedal 17 to fix the rehabilitation trainer's feet on the pedal 17;

Step 3: After the rehabilitation trainer is ready, turn on the power of each part, and the mechanism will start to work;

Step 4: The angle sensor 3 measures the rotation angle of the rotatable short link 6 in the unequal-length parallel link, and the computer obtains and processes the measured data through the amplified interface circuit and compares it with the set threshold Compare to ensure the safety of rehabilitation trainers and institutions;

Step 5: Two bridge circuits composed of strain gauges 14 measure the force exerted by the foot on the pedal 17 in the vertical direction and in the forward and backward movement direction of the pedal 17, and the computer obtains the bridge bridge by amplifying the interface circuit. The output data of the formula circuit can be used to observe the force on the foot of the rehabilitation trainer in real time and adjust the rehabilitation training strategy. Compare to ensure the safety of rehabilitation trainers;

Step 6: When the computer confirms that the obtained angle data and force data meet the requirements of the set threshold, the drive circuit controls the drive motor 4 to rotate, drives the long connecting rod 5 to rotate, and drives the pedal and the rotatable short connecting rod 6 to move, Rehabilitation trainees start rehabilitation training for both joints of the lower limbs;

Step 7: After the rehabilitation training for the joints of the lower extremities is over, the computer controls the drive motor to rotate 4 times through the drive circuit, driving the long connecting rod to the initial position, and the nurse helps the rehabilitation trainer to safely remove the device and turn off the power of the device.

Compared with prior art, the present invention has following advantage:

(1) The present invention adopts a parallel mechanism, in which the cooperation of unequal-length parallel links and pedals can simply and effectively realize the rehabilitation training of knee joints and ankle joints of the lower limbs, and the angle sensor can feedback the posture of the mechanism to ensure that the rehabilitation trainers and the the security of the institution;

(2) The two-dimensional force measuring mechanism in the present invention can monitor in real time the force of the rehabilitation trainer's foot on the vertical direction of the pedal and the force in the direction of forward and backward movement, and can effectively ensure While improving the safety of the rehabilitation trainers, the rehabilitation exercise strategy can also be adjusted to improve the safety, scientificity and efficiency of the rehabilitation exercise;

(3) In the present invention, the foot pedal adopts the support beams on the left and right sides, and the design of the front and rear floating beams makes the structure of the pedals firmer and less prone to damage. The measurement results have a greater impact, and will not affect the function realization of the bridge circuit;

(4) The present invention adopts a simplified and effective control method, the control process is continuous, and the real-time performance is good. The computer can obtain and analyze the measured angle information and force information, and program the drive circuit to control the rotation of the drive motor to realize the rehabilitation training method. Such as the application of the rehabilitation exercise of the knee joint and the ankle joint according to certain rules in the rehabilitation training mechanism for the double joints of the lower limbs.

Description of drawings

Fig. 1 is the structural representation of parallel mechanism among the present invention;

Fig. 2 is the structural representation of pedal among the present invention;

Fig. 3 is the plan view of pedal front end among the present invention;

Fig. 4 is the oblique view of pedal front end among the present invention;

Fig. 5 is the motion form schematic diagram of parallel mechanism in the present invention;

The labels in the drawings are: 0. rotating shaft; 1. seat; 2. short connecting rod fixed at one end; 3. angle sensor; 4. drive motor; 5. long connecting rod; 6. rotatable short connecting rod; 7 .Rotating shaft; 8. Front end of pedal; 9. Front floating beam; 10. Front elastic fixing device; 11. Left supporting beam; 12. Right supporting beam; 13. Rear elastic fixing device; 14. Strain gauge; 15 .Floating beam at the rear end; 16. Peripheral part; 17. Pedal.

Detailed ways:

Taking the structural schematic diagram of the parallel mechanism in Fig. 1 and the structural schematic diagram of the pedal in Fig. 2 as examples below, in conjunction with the plan view of the front end of the pedal in Fig. 3, the oblique view of the front end of the pedal in Fig. 4 and the schematic diagram of the kinematic form of the parallel mechanism in Fig. 5, the specific implementation steps of the present invention are described :

The invention discloses a lower limb double-joint rehabilitation training mechanism based on a parallel mechanism and a two-dimensional force-measuring mechanism, which is characterized in that the lower-limb double-joint rehabilitation training mechanism is composed of two parts: Below the seat 1, it consists of unequal-length parallel links, a short link 2 fixed at one end, a drive motor 4, an angle sensor 3, and rotating shafts 0 and 7. The unequal-length parallel links consist of a rotatable It consists of a long connecting rod 5 and a rotatable short connecting rod 6. The output shaft of the drive motor 4 is connected with the rotating shaft 0 of the long connecting rod 5 near the end of the seat 1. The angle sensor 3 is arranged on the two short connecting rods 2 and 6. Connection; the two-dimensional force measuring mechanism is composed of pedals and two groups of bridge circuits. The elastic fixing device 10, the rear elastic fixing device 13 and the peripheral part 16 are composed of each group of bridge circuits consisting of 4 strain gauges 14, which are used to measure the vertical force of the feet on the pedals 17. It consists of four strain gauges 14 on the four surfaces of the left support beam 11 and the right support beam 12 of the pedal 17, and is used to measure the force of the foot on the pedal 17 in the forward and backward direction. The circuit is composed of 4 strain gauges 14 on the front and rear sides of the pedal 17, the left side support beam 11 and the right side support beam 12; wherein, the angle sensor 3 is connected to the computer through the bus through the enlarged interface circuit, two-dimensional The bridge circuit in the force-measuring mechanism is connected to the computer through the bus through the amplifying interface circuit, and the computer is connected to the control circuit of the driving motor 4 . The driving motor 4 can drive the long connecting rod 5 in the unequal-length parallel connecting rods to rotate, and then drive the pedal and the rotatable short connecting rod 6 to move, so that one motor can drive the rehabilitation exercise training of the two joints of the knee joint and the ankle joint. The sensor 3 is used to measure the rotation angle of the rotatable short link 6 in the unequal-length parallel links, and the computer obtains and processes the measured data by amplifying the interface circuit, thereby controlling the rotation of the driving motor 4, and by comparing with the threshold value, it can Ensure the safety of rehabilitation trainees and the safety of institutions. A bridge circuit composed of four strain gauges 14 on the four surfaces of the left support beam 11 and the right support beam 12 in the pedal 17 can measure the vertical force of the foot on the pedal 17 , and a bridge circuit composed of 4 strain gauges 14 on the front and rear sides of the left side support beam 11 and the right side support beam 12 of the pedal 17 can measure the movement direction of the foot pedal 17 Force, the computer obtains the output data of the bridge circuit by amplifying the interface circuit, and then can observe the force on the foot of the rehabilitation trainer in real time and adjust the rehabilitation training strategy. The safety of the rehabilitation trainer can be guaranteed through threshold setting.

The specific steps are as follows:

Step 1: Preset the threshold by computer before use , the threshold angle , are the pressure thresholds in the four directions of the foot to the pedal 17, in unit N, are respectively the forward and backward rotation angle thresholds of the rotatable short connecting rod 6, unit: degree;

Step 2: The rehabilitation trainer sits on the seat 1 and uses the front elastic fixing device 10 and the rear elastic fixing device 13 on the pedal 17 to fix the rehabilitation trainer's feet on the pedal 17;

Step 3: After the rehabilitation trainer is ready, turn on the power of each part, and the mechanism will start to work;

Step 4: The angle sensor 3 measures the rotation angle of the rotatable short link 6 in the unequal-length parallel link, and the computer obtains and processes the measured data through the amplified interface circuit and compares it with the set threshold Compare to ensure the safety of rehabilitation trainers and institutions;

Step 5: Two bridge circuits composed of strain gauges 14 measure the force exerted by the foot on the pedal 17 in the vertical direction and in the forward and backward movement direction of the pedal 17, and the computer obtains the bridge bridge by amplifying the interface circuit. The output data of the formula circuit can be used to observe the force on the foot of the rehabilitation trainer in real time and adjust the rehabilitation training strategy. Compare to ensure the safety of rehabilitation trainers;

Step 6: When the computer confirms that the obtained angle data and force data meet the requirements of the set threshold, the drive circuit controls the drive motor 4 to rotate, drives the long connecting rod 5 to rotate, and drives the pedal and the rotatable short connecting rod 6 to move, Rehabilitation trainees start rehabilitation training for both joints of the lower limbs;

Step 7: After the rehabilitation training for the joints of the lower extremities is over, the computer controls the drive motor to rotate 4 times through the drive circuit, driving the long connecting rod to the initial position, and the nurse helps the rehabilitation trainer to safely remove the device and turn off the power of the device.

Fig. 3 and Fig. 4 respectively present the schematic structure of the front end of the pedal 8 in the angle of top view and oblique view, and Fig. 5(a) shows that the rehabilitation trainer moves forward under the drive of the mechanism to reach the forward threshold (b) indicates the initial state set by the mechanism, (c) indicates that the rehabilitation trainer moves backwards to reach the backward threshold driven by the mechanism The state at the time, marked in the figure are respectively the forward and backward rotation angle thresholds of the rotatable short connecting rod 6, is the rehabilitation training angle of the ankle joint of the rehabilitation trainer, and its angle change can be seen from the figure.

The basic principles, main features and advantages of the present invention have been shown and described above. Those skilled in the industry should understand that the present invention is not limited by the above-mentioned embodiments. What are described in the above-mentioned embodiments and the description only illustrate the principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention will also have Variations and improvements are possible, which fall within the scope of the claimed invention. The protection scope of the present invention is defined by the appended claims and their equivalents.

Claims (6)

1. A lower limb double-joint rehabilitation training mechanism based on a parallel mechanism and a two-dimensional force-measuring mechanism, characterized in that the lower limb double-joint rehabilitation training mechanism is composed of a parallel mechanism and a two-dimensional force-measuring mechanism: the parallel mechanism is installed in a seat Below the chair (1), it consists of unequal-length parallel links, a short link (2) with one end fixed, a drive motor (4), an angle sensor (3) and rotating shafts (0) and (7). The equal-length parallel link is made up of a rotatable long link (5) and a rotatable short link (6), and the drive motor (4) output shaft and the long link (5) are close to the seat (1 ) end of the rotating shaft (0) connected, the angle sensor (3) is set at the junction of two short connecting rods (2) and (6); the two-dimensional force measuring mechanism is composed of pedals and two sets of bridge circuits, the pedals include Pedal (17), left support beam (11), right support beam (12), front-end fixing device and peripheral part (16), each group of bridge circuit is made up of (4) strain gauges (14), The bridge circuit that is used to measure the force of the foot on the vertical direction of the pedal (17) is composed of the left side support beam (11) and the right side support beam (12) of the pedal (17) on four surfaces in total. (4) sheet strain gauges (14) are formed, and the bridge circuit that is used to measure the force on the front and back movement direction of foot pedal (17) is made up of pedal (17) left support beam (11) and The right support beam (12) is composed of (4) strain gauges (14) on the front and rear sides; wherein, the angle sensor (3) is connected to the computer through the interface circuit, and the bridge type in the two-dimensional force measuring mechanism The circuit is connected to the computer through the interface circuit, and the computer is connected to the control circuit of the drive motor (4). The drive motor (4) can drive the long link (5) in the unequal-length parallel links to rotate, and then drive the pedal and the rotatable short link. The movement of the connecting rod (6) realizes the rehabilitation exercise training of two joints driven by a motor, the knee joint and the ankle joint, and the angle sensor (3) is used to measure the rotatable short connecting rod (6) in the unequal-length parallel connecting rod For the rotation angle, the computer acquires and processes the measured data through the interface circuit, thereby controlling the rotation of the drive motor (4), and comparing with the threshold, the safety of the rehabilitation trainer and the safety of the mechanism can be guaranteed. 2. A lower limb double-joint rehabilitation training mechanism based on a parallel mechanism and a two-dimensional force-measuring mechanism according to claim 1, characterized in that: said pedal is also provided with a rear-end fixing device to further strengthen foot fixation. 3. A lower limb double-joint rehabilitation training mechanism based on a parallel mechanism and a two-dimensional force-measuring mechanism according to claim 2, wherein the front-end fixing device and the rear-end fixing device are respectively elastic fixing devices. 4. A kind of lower limb double-joint rehabilitation training mechanism based on parallel mechanism and two-dimensional force measuring mechanism according to claim 1, it is characterized in that: described angle sensor (3) is to be connected with computer by bus through amplifying interface circuit, two The bridge circuit in the force-dimension measuring mechanism is connected with the computer through the bus through the amplifying interface circuit. 5. A kind of lower extremity dual-joint rehabilitation training mechanism based on a parallel mechanism and a two-dimensional force measuring mechanism according to claim 1, characterized in that: the front and rear ends of the pedal are respectively provided with a front floating beam (9) and a rear floating beam (15) in order to firm pedal. 6. The method for using the lower limb double-joint rehabilitation training mechanism based on the parallel mechanism and the two-dimensional force measuring mechanism according to claims 1 to 5, the specific steps are as follows: Step 1: Preset the thresholds z ₁ , z ₂ , z ₃ , z ₄ through the computer before use, and the threshold angles θ ₁ , θ ₂ , z ₁ , z ₂ , z ₃ , z ₄ are respectively the feet to the pedals (17) Pressure thresholds in the four directions, unit N, θ ₁ and θ ₂ are respectively the forward and backward rotation angle thresholds of the rotatable short connecting rod (6), unit: degree; Step 2: The rehabilitation trainer sits on the seat (1) and uses the front elastic fixing device (10) and the rear elastic fixing device (13) on the foot board (17) to fix the rehabilitation trainer's feet on the foot board (17) on; Step 3: After the rehabilitation trainer is ready, turn on the power of each part, and the mechanism will start to work; Step 4: The angle sensor (3) measures the rotation angle of the rotatable short link (6) in the unequal-length parallel link, and the computer obtains and processes the measured data through the amplified interface circuit and compares them with the set thresholds θ ₁ , θ ₂ comparison to ensure the safety of rehabilitation trainers and institutions; Step 5: Two bridge circuits formed by strain gauges (14) measure the force exerted by the foot on the vertical direction of the pedal (17) and on the forward and backward movement direction of the pedal (17) , the computer obtains the output data of the bridge circuit by amplifying the interface circuit, and then can observe the force on the foot of the rehabilitation trainer in real time and adjust the rehabilitation training strategy. By comparing with the set threshold z ₁ , z ₂ , z ₃ , z ₄ , to ensure the safety of rehabilitation trainers; Step 6: When the computer confirms that the obtained angle data and force data meet the requirements of the set threshold, it controls the rotation of the drive motor (4) through the drive circuit, drives the long connecting rod (5) to rotate, and drives the pedal and the rotatable short connecting rod (6), the rehabilitation trainer starts the rehabilitation training of the joints of the lower limbs; Step 7: After the rehabilitation training for the joints of the lower limbs is over, the computer controls the drive motor (4) to rotate through the drive circuit, driving the long connecting rod to the initial position, and the nurse helps the rehabilitation trainer to safely remove the device and turn off the power of the device.