CN106038170A - Pedal-type lower limb rehabilitation training robot capable of measuring plantar pressure distribution - Google Patents

Abstract

The invention discloses a pedal-type lower limb rehabilitation training robot capable of measuring the distribution of plantar pressure. The pedal can run in the form of rotation of the bicycle pedal under the drive of the motor; the pedal has a pedal bottom plate, and is connected to the pedal support through elastic beams, and sensitive elements are set on each elastic beam to form a sensing unit; a mathematical model is established for the transmission The sensor unit is calibrated, and the measured force on the pedal base is detected to obtain the strain detection signal of the sensitive element on each elastic beam, and the distribution of the measured force on the pedal base is obtained by using a mathematical model. The invention can provide a basis for formulating a training program for a foot-operated lower limb rehabilitation training robot.

Description

A pedal-type lower limb rehabilitation training robot that can measure plantar pressure distribution

technical field

The invention belongs to the technical field of rehabilitation exercise training equipment, in particular to a foot-operated lower limb rehabilitation training robot capable of measuring plantar pressure distribution.

Background technique

As a product of the combination of robotics and rehabilitation medicine, rehabilitation machines can help therapists be freed from repetitive rehabilitation work, allowing patients to stimulate the nervous system through appropriate training to gradually restore the motor function of the limbs. The foot-operated lower limb rehabilitation training robot is widely used in various rehabilitation institutions due to its simple structure, low cost, safety and reliability, and has achieved good clinical rehabilitation results in patients with stroke, muscle atrophy, brain injury, and spinal cord injury.

At present, most rehabilitation training devices mainly focus on the effectiveness and economy of treadmill exercise. Due to the lack of exercise information feedback, it is difficult for patients to adjust exercise parameters reasonably, resulting in insufficient scientificity and safety of rehabilitation training for patients.

Contents of the invention

The present invention is to avoid the shortcomings of the above-mentioned prior art, and provides a foot-operated lower limb rehabilitation training robot that can measure the distribution of plantar pressure. It is of great significance for clinical medical diagnosis, disease degree measurement, and postoperative curative effect evaluation.

The present invention adopts following technical scheme for solving technical problems:

The structural characteristics of the foot-operated lower limb rehabilitation training robot capable of measuring plantar pressure distribution in the present invention are: the foot-operated lower limb rehabilitation training robot is built with a motor and a reducer in a fixed frame, driven by a motor and driven by a crank The pedals are located on both sides of the fixed frame, so that a pair of pedals can be driven by the motor to rotate in the form of bicycle pedals;

The structure of the pedal is:

One foot pedal, one foot to be tested is placed on the determined position of the pedal base, and the determined position refers to the division of each area on the pedal base in the following manner: the first phalange area, the third to the third The five phalanges, the metatarsal area and the heel, the metatarsal area includes the first metatarsal area, the second metatarsal area and the third to fifth metatarsal areas; the heel is divided into heel medial area and heel lateral area , let: the side where the first phalanx is located is the first side of the pedal floor, and the side where the fifth phalanx is located is the second side of the pedal floor;

A pedal support, the pedal support is an upright side panel arranged according to the outer contour shape of the pedal floor, the bottom edge of the side panel is connected with the edge of the pedal floor by elastic beams at different positions , a support shaft is arranged on one side of the side wall, one end of the crank is installed on the rotating shaft of the motor, and the other end is installed on the supporting shaft, so that the pedal can rotate with the crank with the rotating shaft of the motor as the rotation center; Sensitive elements are arranged on each elastic beam to form a sensing unit;

The method for detecting the plantar pressure of the foot-operated lower limb rehabilitation apparatus is set as follows:

Step a. Distributing stress points in different areas of the pedal floor, loading a force [F] perpendicular to the bottom plate on the stress points, and obtaining a strain detection signal [ε] from the sensitive elements on each elastic beam; according to The loading force [F] on the force point and the mathematical model of each strain detection signal [ε] are established as: [C]×[F]=[ε], the calibration of the sensing unit is completed, and the constant matrix [C] is obtained ;

Step b. For the measured force on the pedal base, detect and obtain the strain detection signals of the sensitive elements on each elastic beam, and use the mathematical model to obtain the distribution of the measured force on the pedal base.

The characteristics of the foot-operated lower limb rehabilitation training robot capable of measuring the plantar pressure distribution of the present invention are also:

Set the measured force as: the force F ₁ at the position of the first metatarsal head, the force F ₂ at the position of the second metatarsal head, and the force at the center of the third to fifth metatarsals F ₃ , the force F ₄ on the medial area of the heel, and the force F ₅ on the lateral area of the heel;

The elastic beams set in the sensing unit are respectively:

a first beam and a second beam spaced apart on the edge of the pedal plate on the first side of the pedal plate corresponding to where the metatarsal region is located;

the third beam on the edge of the pedal plate on the second side of the pedal plate, corresponding to where the metatarsal area is located;

a fourth beam on the edge of the pedal plate on the first side of the pedal plate corresponding to where the medial heel area is located;

a fifth beam on the edge of the plate on the second side of the footrest plate, corresponding to where the lateral area of the heel is located;

In addition, the first sensitive element is symmetrically arranged on the top surface and the bottom surface of the first beam, the second sensitive element is symmetrically arranged on the top surface and the bottom surface of the second beam, and the third sensitive element is symmetrically arranged on the top surface and the bottom surface of the third beam , the fourth sensitive element is symmetrically arranged on the top surface and the bottom surface of the fourth beam, and the fifth sensitive element is symmetrically arranged on the top surface and the bottom surface of the fifth beam.

The characteristics of the foot-operated lower limb rehabilitation training robot capable of measuring the plantar pressure distribution of the present invention are also that: the plantar pressure detection method of the foot-operated lower limb rehabilitation equipment is:

First of all, according to step a, five stress points are distributed one by one corresponding to the area where the force to be measured is located on the bottom plate of the pedal, and a force [F] perpendicular to the bottom plate is loaded on the force point. The sensitive element obtains the strain detection signal [ε]; according to the loading force [F] on the force point, and each strain detection signal [ε], the mathematical model is established as: [C]×[F]=[ε], and the transmission is completed. Calibration of the sense unit, and obtain a 5×5 constant matrix [C];

Then, according to step b, use formula (1) to calculate and obtain the acting forces F ₁ , F ₂ , F ₃ , F ₄ , and F ₅ as follows:

In formula (1), [C] ^-1 is the inverse matrix of 5 * 5 constant matrix [C];

ε ₁ , ε ₂ , ε ₃ , ε ₄ , and ε ₅ are the strain signals detected by the first sensitive element, the second sensitive element, the third sensitive element, the fourth sensitive element, and the fifth sensitive element, respectively.

Compared with the prior art, the beneficial effects of the present invention are reflected in:

1. The present invention can monitor the size and distribution of plantar force in the training process in real time, and can improve the scientificity and safety of rehabilitation training for the acquisition of plantar pressure information

2. The present invention can provide an objective basis for the evaluation of lower limb rehabilitation, and is used to assist patients in left-right symmetry training and identify different walking habits such as valgus and valgus;

3. The detection method of the present invention is convenient and reliable, not only for static evaluation, but also for dynamic evaluation;

4. The present invention is simple in structure, safe and reliable, and easy to operate;

5. For patients with stroke, muscular atrophy, brain injury, spinal cord injury, etc., the present invention can be used for training to enhance muscle strength, promote blood circulation, and gradually restore limb motor function.

6. The present invention is suitable for use in various occasions such as hospitals and ordinary families.

Description of drawings

Fig. 1 is a structural representation of the present invention;

Fig. 2 is a schematic diagram of the pedal structure in the present invention;

Fig. 3 is a schematic diagram of the divided regions of the pedal floor in the present invention;

Labels in the figure: 1 fixed frame, 2 pedals, 3 left leg protector, 4 right leg protector, 5 first beam, 6 second beam, 7 pedal support, 8 fourth beam, 9 fifth beam, 10 The third beam, 11 pedal base plates.

detailed description

Referring to Fig. 1, the foot-operated lower limb rehabilitation training robot that can measure the distribution of plantar pressure in the present embodiment is that a motor and a reducer are built in a fixed frame 1, and a pedal 2 driven by a motor and driven by a crank is positioned on the fixed machine. On both sides of the frame 1, a pair of pedals 2 can be operated in the form of rotation of bicycle pedals driven by the motor; this form can be used for functional training for patients with stroke, muscle atrophy, brain injury, spinal cord injury, etc. To enhance muscle strength, promote blood circulation, and gradually restore limb motor function; the left leg protector 3 and right leg protector 4 shown in Figure 1 are used to prevent the patient from falling off the pedal due to insufficient leg strength, resulting in harm. The user sits on the seat and places the left and right feet on the pedals on the left and right sides. The left leg protector 3 is fixed on the left leg, the right leg protector 4 is fixed on the right leg, and the motor is started to rotate. You can move along with the pedals for functional training.

Referring to Fig. 2 and Fig. 3, the structural form of pedal 2 in the present embodiment is:

A foot pedal base plate 11, a foot to be measured is placed on the determined position of the pedal base plate 11, and the determined position refers to dividing each area on the pedal base plate 11 as follows: the first phalanx region, the third to the fifth The phalanx region, the metatarsal region and the heel, the metatarsal region includes the first metatarsal region, the second metatarsal region and the third to fifth metatarsal regions; the heel is divided into a heel medial region and a heel lateral region, Order: the side where the first phalanx is located is the first side of the pedal base, and the side where the fifth phalanx is located is the second side of the pedal base 11 .

A pedal support 7, the pedal support 7 is an upright side panel arranged according to the outer contour shape of the pedal base plate 11, and the bottom edge of the side panel is connected with the edge of the pedal base plate 11 with elastic beams at different positions , one side of the side panel is provided with a supporting shaft, one end of the crank is installed on the rotating shaft of the motor, and the other end is installed on the supporting shaft, so that the pedal 2 can rotate with the crank with the rotating shaft of the motor as the center of rotation; Sensitive elements are arranged on each elastic beam to form a sensing unit;

The plantar pressure detection method for setting foot-operated lower limb rehabilitation equipment is as follows:

Step a. Distribute stress points in different areas of the pedal floor 11, use the software ansys workbench to load a force [F] perpendicular to the floor at the stress points, and obtain strain detection signals [ε] from the sensitive elements on each elastic beam , load multiple times and obtain multiple sets of strain detection signals correspondingly; establish a mathematical model based on the loading force [F] on the stress point and each strain detection signal [ε]: [C]×[F]=[ε], complete Calibrate the sensing unit and obtain a constant matrix [C]; where [F] is the matrix expression of multiple loading forces, [ε] is the matrix expression of multiple sets of strain detection signals, and [C] is the mathematical model The matrix expression form of the constant in the middle, that is: constant matrix; the constant matrix [C] is obtained through software simulation calibration, and can also be obtained through experimental calibration.

Step b. For the measured force on the pedal base 11 , detect and obtain the strain detection signals of the sensitive elements on each elastic beam, and use the mathematical model to obtain the distribution of the measured force on the pedal base 11 .

In a specific implementation, the number and position of the elastic beams in the pedal 2 are determined according to the distribution of the plantar force to be detected.

In this embodiment, in order to obtain the force distribution of the first metatarsal area, the second metatarsal area, the third to the fifth metatarsal area, the medial area of the heel and the lateral area of the foot during the rehabilitation training of the patient, set Determine the measured force as: the force F ₁ at the position of the first metatarsal head, the force F ₂ at the position of the second metatarsal head, the force F ₃ at the center of the third to fifth metatarsals, The force F ₄ in the inner area of the heel, and the force F ₅ in the outer area of the heel; the corresponding elastic beams set in the sensing unit are respectively: located on the first side of the sole plate of the pedal, corresponding to the metatarsal The first beam 5 and the second beam 6 spaced apart on the edge of the foot plate at the position of the region; the third beam 10 on the edge of the foot plate at the second side of the foot plate corresponding to the position of the metatarsal region; The fourth beam 8 on the edge of the soleplate on the first side of the soleplate, corresponding to the location of the inner heel area; the fifth beam 9 on the edge of the soleplate on the second side of the soleplate, corresponding to the location of the outer heel area and have: the first sensitive element is symmetrically arranged on the top surface and the bottom surface of the first beam 5, the second sensitive element is symmetrically arranged on the top surface and the bottom surface of the second beam 6, and the third sensitive element is symmetrically arranged on the third beam 10 The top surface and the bottom surface, the fourth sensitive element is symmetrically arranged on the top surface and the bottom surface of the fourth beam 8, the fifth sensitive element is symmetrically arranged on the top surface and the bottom surface of the fifth beam 9, and the detection method is:

First, according to step a, five force points are distributed one by one corresponding to the area where the force to be measured is located on the pedal bottom plate 11, and the force [F] perpendicular to the bottom plate is loaded on the force point, and the elastic beams on each elastic beam The sensitive element obtains the strain detection signal [ε]; the mathematical model is established according to the loading force [F] on the stress point and each strain detection signal [ε]: [C]×[F]=[ε], and the sensor is completed Calibrate the unit and obtain a 5×5 constant matrix [C];

Then, according to step b, use formula (1) to calculate and obtain the acting forces F ₁ , F ₂ , F ₃ , F ₄ , and F ₅ as follows:

In formula (1), [C] ^-1 is the inverse matrix of 5 * 5 constant matrix [C];

ε ₁ , ε ₂ , ε ₃ , ε ₄ , and ε ₅ are the strain signals detected by the first sensitive element, the second sensitive element, the third sensitive element, the fourth sensitive element, and the fifth sensitive element, respectively.

Claims (3)

1. A foot-operated lower limb rehabilitation training robot that can measure plantar pressure distribution is characterized in that: said foot-operated lower limb rehabilitation training robot is built-in motor and speed reducer in the fixed frame (1), and is controlled by motor The pedals (2) driven and driven by the crank are located on both sides of the fixed frame (1), so that the pair of pedals (2) can be driven by the motor to rotate in the form of bicycle pedals; The structural form of described pedal (2) is: A foot pedal base plate (11), a measured foot is placed on the definite position of the pedal base plate (11), and the definite position refers to dividing each area on the pedal base plate (11) as follows: The first phalanx area, the third to fifth phalanx area, the metatarsal area and the heel, the metatarsal area includes the first metatarsal area, the second metatarsal area and the third to the fifth metatarsal area; the heel is divided into Heel medial area and heel lateral area, order: the side where the first phalanx is located is the first side of the pedal base plate, and the side where the fifth phalanx is located is the second side of the pedal base plate (11); A pedal support (7), the pedal support (7) is an upright side panel arranged according to the outer contour shape of the pedal base plate (11), the bottom edge of the side panel and the pedal base plate (11) The edges of the crank are connected by elastic beams at different positions, and a support shaft is provided on one side of the side panel, one end of the crank is installed on the rotating shaft of the motor, and the other end is installed on the support shaft, so that the pedal (2) It can rotate with the crank with the rotating shaft of the motor as the rotation center; sensitive elements are arranged on the elastic beams to form a sensing unit; The method for detecting the plantar pressure of the foot-operated lower limb rehabilitation apparatus is set as follows: Step a, distribute stress points in different regions of the pedal floor (11), load the force [F] perpendicular to the bottom plate on the stress points, and obtain the strain detection signal [ε] by the sensitive elements on the elastic beams ]; according to the loading force [F] on the force point, and each strain detection signal [ε], the mathematical model is established as: [C]×[F]=[ε], the calibration of the sensing unit is completed, and the constant matrix is obtained [C]; Step b, for the measured force on the pedal base (11), detect and obtain the strain detection signals of the sensitive elements on each elastic beam, and use the mathematical model to obtain the distribution of the measured force on the pedal base (11) . 2. the foot-operated lower limb rehabilitation training robot of measurable plantar pressure distribution according to claim 1, is characterized in that: Set the measured force as: the force F ₁ at the position of the first metatarsal head, the force F ₂ at the position of the second metatarsal head, and the force at the center of the third to fifth metatarsals F ₃ , the force F ₄ on the medial area of the heel, and the force F ₅ on the lateral area of the heel; The elastic beams set in the sensing unit are respectively: a first beam (5) and a second beam (6) spaced apart on the edge of the foot plate corresponding to the location of the metatarsal region on the first side of the foot plate; a third beam (10) on the edge of the footrest floor corresponding to the location of the metatarsal region on the second side of the footrest floor; a fourth beam (8) on the edge of the footrest floor on the first side of the footrest floor corresponding to the position of the inner heel area; The fifth beam (9) on the edge of the floor corresponding to the location of the outer heel area on the second side of the footrest floor; And there are: the first sensitive element is symmetrically arranged on the top surface and the bottom surface of the first beam (5), the second sensitive element is symmetrically arranged on the top surface and the bottom surface of the second beam (6), and the third sensitive element is symmetrically arranged on the third beam (6). The top and bottom surfaces of the beam (10), the fourth sensitive element is symmetrically arranged on the top and bottom surface of the fourth beam (8), and the fifth sensitive element is symmetrically arranged on the top and bottom surface of the fifth beam (9). 3. The foot-operated lower limb rehabilitation training robot capable of measuring plantar pressure distribution according to claim 2, characterized in that: the plantar pressure detection method of the foot-operated lower limb rehabilitation apparatus is: First, according to step a, five stress points are distributed one by one corresponding to the area where the measured force is located on the pedal floor (11), and a force [F] perpendicular to the bottom plate is loaded on the force point, by each The sensitive element on the elastic beam obtains the strain detection signal [ε]; the mathematical model is established according to the loading force [F] on the stress point and each strain detection signal [ε]: [C]×[F]=[ε], Complete the calibration of the sensing unit and obtain a 5×5 constant matrix [C]; Then, according to step b, use formula (1) to calculate and obtain the acting forces F ₁ , F ₂ , F ₃ , F ₄ , and F ₅ as follows: In formula (1), [C] ^-1 is the inverse matrix of 5 * 5 constant matrix [C]; ε ₁ , ε ₂ , ε ₃ , ε ₄ , and ε ₅ are the strain signals detected by the first sensitive element, the second sensitive element, the third sensitive element, the fourth sensitive element, and the fifth sensitive element, respectively.