CN206491990U - Rehabilitation of anklebone system - Google Patents

Abstract

The utility model relates to an ankle joint rehabilitation system. A host computer is connected to a motor controller, and sends motion mode commands to the motor controller to control the motor controller; the motor controller is connected to a DC brushless motor arranged on a mechanical transmission device. Output the control signal to the DC brushless motor to control it; at the same time receive the motor position signal fed back by the inductive pulse encoder set on the mechanical transmission device, and perform closed-loop control on the mechanical transmission device. The utility model issues commands to the ankle joint rehabilitation equipment and monitors and controls the action and operation status of the robot to ensure that the robot can effectively cooperate with the patient to complete the ankle joint rehabilitation training according to the requirements, with high precision and strong anti-interference ability, and the collected voltage signal shakes Small, easy to handle, ensuring accurate control of the motor position is to ensure the safety of rehabilitation.

Description

ankle rehabilitation system

technical field

The utility model relates to the field of auxiliary medical rehabilitation training equipment, in particular to an ankle joint rehabilitation system.

Background technique

Rehabilitation robot is an important branch of medical robot. Its research runs through many fields such as rehabilitation medicine, biomechanics, mechanics, mechanics, electronics, materials science, computer science and robotics. It has become an international robotics field. Research hotspots.

Ankle joint injuries are the most common ankle ligament injuries. If the treatment is not timely or thorough, it will easily lead to excessive relaxation of ankle ligaments, joint instability, easy to cause repeated sprains, and cause sequelae such as ankle joint dysfunction, which will seriously affect walking function. . In most cases of ankle injuries, after hospital treatment, the recovery time is generally 6-18 months. During this period, most people cannot walk normally and will feel obvious pain. At this time, physical therapy is especially needed. Auxiliary rehabilitation treatment (such as foot relaxation and massage, etc.) must undergo repeated step-by-step training to restore the damaged ankle joint.

At present, the existing ankle joint rehabilitation training equipment on the market has simple functions, and the recovery of ankle joint motion function is insufficient. It cannot realize automatic continuous reciprocating and slow movement, and improper use may easily cause re-injury of the ankle joint. The price of clinical equipment used in some hospitals Expensive, and requires professional guidance to use, not conducive to home use.

Utility model content

Aiming at the deficiencies of the existing technology, the utility model provides an ankle joint that can issue commands to the ankle joint rehabilitation equipment and monitor and control the movement and operation status of the robot, so as to ensure that the robot can effectively cooperate with the patient to complete the ankle joint rehabilitation training according to the requirements. rehabilitation system.

The technical scheme that the utility model adopts for realizing the above object is:

An ankle joint rehabilitation system, the host computer is connected to the motor controller, sends motion mode commands to the motor controller, and controls the motor controller;

The motor controller is connected to the brushless DC motor 2 set on the mechanical transmission device, and outputs the control signal to the brushless DC motor 2 to control it; at the same time, it receives the motor fed back by the inductive pulse encoder 1 set on the mechanical transmission device The position signal is used for closed-loop control of the mechanical transmission.

The mechanical transmission includes:

The inductive pulse encoder 1 is coaxially connected to the brushless DC motor 2, and the other end is connected to the motor controller to send the control signal of the motor controller. At the same time, the corresponding pulse signal is generated according to the rotation of the brushless DC motor 2 and fed back to the motor controller. device;

One end of the torque sensor 5 is coaxially connected to the reduction box 3 through the input coupling 16, and the reduction box 3 is coaxially connected to the brushless DC motor 2; the other end is coaxially connected to the output shaft through the output coupling 14, and the output shaft passes through the connecting piece 7 Attach the foot pedal 9.

The output shaft includes a bearing support 6 fixed on the bottom plate 10. Two low-fat grease-enclosed ball bearings are arranged in the bearing support 6. The inner rings of the two bearings are axially fixed by the sleeve, and the outer rings are fixed by the shaft. The shoulder and the end cover 13 are axially fixed.

It also includes an angle sensor support 12 fixed on the bearing end cover 13, the housing 11 is connected to the angle sensor support 12 through threads, the angle sensor 8 fixes its outer ring through the housing 11, and the inner ring is sleeved on the D-shaped shaft to detect the shaft in real time. angle of rotation.

The bearing end cover 13 is fixed on the bearing support 6 through threads, and a limit slide groove is arranged inside, which cooperates with the pin 15 fixedly arranged on the connecting piece 7 to mechanically limit the rotation of the ankle joint.

The brushless DC motor 2 is a disc-type brushless DC motor provided with a Hall sensor. The current rotor position of the motor is detected by the Hall sensor, and an excitation current in a corresponding direction is generated to drive the brushless DC motor 2 to rotate.

The torque sensor 5 adopts strain gauge electrical measurement technology.

The input coupling 16 and the output coupling 14 are flange couplings, which are connected with the shaft through flat keys, and the transmission gap is eliminated through set screws.

The motor position signal is:

Among them, Θ _m is the motor rotation angle, Θ _d is the expected rotation angle of the ankle joint, F is the joint torque, M is the inertia parameter, B is the damping, K is the stiffness, and s is the complex variable.

The angle range defined by the limiting chute is that the maximum rotation angle of the patient's dorsiflexion is 40°, and the maximum rotation angle of plantarflexion is 50°.

The utility model has the following beneficial effects and advantages:

1. The torque sensor in the utility model can measure the force information of the human foot or other external objects on the ankle joint device, and use this force information to realize force protection and corresponding force control for the ankle joint device. This torque sensor is relatively matched with the human ankle joint movement, and can measure the force information of the ankle joint well. The accuracy is relatively high, the measurement value is stable, and the response is sensitive.

2. The inductive pulse encoder of this utility model can detect the rotation angle of the motor in real time, and use this angle information to realize accurate position control of the motor. For wearable rehabilitation ankle joint equipment, ensuring accurate control of the motor position is the guarantee Rehabilitation safety, high precision, easy to read position data, high programmable, good configurability, high detection response time.

3. The utility model detects the position information of the end of the ankle joint rehabilitation equipment in real time through the angle sensor, so the movement position of the ankle joint can be realized, and the accurate control of the end position can be easily realized, with high precision. During the experiment process, it is convenient for detection and collection. The anti-interference ability is strong, and the jitter of the collected voltage signal is small, which is convenient for processing.

Description of drawings

Fig. 1 is a system structure block diagram of the present utility model;

Fig. 2 is a structural diagram of the mechanical transmission device of the present utility model;

Fig. 3 is the installation structure diagram of the angle sensor of the present utility model;

Fig. 4 is a schematic diagram of the position-limiting structure of the present utility model;

Fig. 5 is the schematic diagram of installation of the torque sensor of the present utility model;

Among them, 1 is an inductive pulse encoder, 2 is a DC brushless motor, 3 is a gearbox, 4 is a motor support, 5 is a torque sensor, 6 is a bearing support, 7 is a connector, 8 is an angle sensor, 9 10 is a base plate, 11 is a shell, 12 is an angle sensor support, 13 is a bearing cover, 14 is an output coupling, 15 is a pin, and 16 is an input coupling.

detailed description

Below in conjunction with accompanying drawing and embodiment the utility model is described in further detail.

As shown in Figure 1, it is a block diagram of the system structure of the utility model of the utility model.

The upper computer adopts a PC with powerful computing power, and its main function is to send motor control commands to the lower computer, and at the same time receive the feedback data from the robot angle sensor 8, torque sensor 5 and the feedback data from the lower computer motor controller, and through programming A good user interface program realizes functions such as human-computer interaction between the user and the robot.

The lower computer uses PC104, which forms a closed-loop control of motor current, speed, and position corresponding to the motor of the robot, and directly controls the brushless DC motor 2 to execute the commands issued by the upper computer; It can issue commands to the ankle joint rehabilitation equipment and monitor and control the movement and operation status of the robot, so as to ensure that the robot can effectively cooperate with the patient to complete the ankle joint rehabilitation training as required.

The patient sits on the seat, and the support frame provides a certain amount of support for the patient's calf. The doctor performs rehabilitation operations through the computer monitor, sets the corresponding rehabilitation mode for the patient, and helps the patient's ankle joints move; the entire mechanical transmission part is placed on the bottom frame superior.

As shown in Figure 2, it is a structural diagram of the mechanical transmission device of the present invention.

The inductive pulse encoder 1, the disc brushless DC motor 2, the reduction box 3, the torque sensor 5, the bearing support 6, the connector 7, and the angle sensor 8 are coaxially installed on the mechanical structure; the reduction box 3 passes through The motor support 4 is fixed on the bottom plate 10, the inductive pulse encoder 1 can count 512 pulses per revolution, and realizes the precise control of the motor output shaft; the disc-type brushless DC motor 2 with Hall sensors is used to provide driving force Output; reduction box 3, used to reduce the speed and increase the driving torque.

The transmission part of the ankle joint rehabilitation equipment includes: an inductive pulse encoder connected in series, a DC disc brushless motor with a Hall sensor, a gearbox, an input coupling, a torque sensor, an output coupling, and low-fat grease Enclosed ball bearings, bushings, connectors, also includes: motor controller, data lines to and power for inductive pulse encoders, and hall sensor data lines and power lines to brushless DC motors , and connected to the power line of the brushless motor, the current rotor position of the motor is detected by the Hall sensor signal to generate an excitation current in the corresponding direction to drive the brushless motor to rotate, and the rotation of the motor will drive the coaxially installed inductive pulse encoder to generate a corresponding The pulse signal is input to the motor controller. The motor controller accurately controls the rotation speed and position of the motor rotor by counting the pulse signal of the encoder, and controls the output torque of the motor by controlling the current flowing through the motor power line. The rotor of the brushless DC motor usually has a high rated speed, and a gear box with an appropriate reduction ratio is installed on the output shaft of the motor to reduce the joint speed and increase the drive torque.

Preferably, an angle sensor is installed at the end of the output shaft. The output of the sensor is an absolute value, and its value will not be lost when the power is turned off. Whenever the device is powered on, the absolute position of the output shaft can be obtained at any time, which is used to supplement the inductive The position information provided by the pulse encoder is given to the motor controller, so as to realize the absolute position control of the output shaft of the torque sensor.

Preferably, the torque sensor of the mechanical transmission part of the ankle joint rehabilitation equipment adopts strain gauge electrical measurement technology.

Preferably, the angle control of the ankle joint adopts an impedance control algorithm, which uses the signal of the torque sensor to control the output torque of the joint, so as to ensure the safety of the patient's rehabilitation process. The algorithm uses the following formula to calculate the joint output angle, which is the position information provided by the inductive pulse encoder:

Among them, Θ _m is the rotation angle of the motor, Θ _d is the desired rotation angle of the ankle joint, and F is the joint torque, that is, the output signal of the torque sensor. The size of the deviation of the expected rotation angle is generated through frequency domain transformation, and the deviation from the expected rotation angle is used to generate the motor angle control command and Send to the motor controller; M is the inertia parameter, B is the damping, K is the stiffness, and s is the complex variable.

The ankle joint is the most weight-bearing flexion joint in the human body. It is composed of the distal tibia, talus, fibula and surrounding ligaments. When standing, the weight of the whole body falls on the ankle joint. Walking and jumping activities in daily life mainly rely on dorsiflexion and plantar flexion of the ankle joint. When various reasons cause multiple fractures in the whole body, paraplegia, or fractures of the lower limbs of the elderly, causing patients to stay in bed for a long time, it will cause serious complications, that is, ankle plantar flexion deformity, and even if the patient can stand up, he cannot walk normally.

The rehabilitation device proposed by the utility model can help the ankle joint to dorsiflexion 0:40° and plantarflexion 0:50° under passive conditions, and can set different movement angles and times according to the individual conditions of patients, and can be slow and continuous Back-and-forth exercise will have a good effect on preventing ankle stiffness and lower limb muscle atrophy for those patients whose ankle joints cannot or are difficult to perform active activities.

As shown in Fig. 3, it is a diagram of the installation structure of the angle sensor of the present invention.

The angle sensor 8 fixes its outer ring through the housing 11, and the inner ring is sleeved on the D-shape shaft to detect the rotation angle of the shaft in real time. The housing 11 is connected to the angle sensor support 12 by threads, and the angle sensor support 12 is fixed on the bearing end cover 13. .

As shown in Fig. 4, it is a schematic diagram of the position-limiting structure of the present invention.

The bearing end cover 14 is fixed on the bearing support 6 through threads, and the chute on the bearing end cover 14 is a mechanical limit to the rotation of the ankle joint, which further ensures the safety of human-computer interaction. The pin 15 is installed on the connecting piece of the rotating shaft and the pedal, and rotates together with the rotating shaft. The bearing end cover 14 limits the maximum rotation angle of the patient's dorsiflexion to 40°, and the maximum rotation angle of the plantarflexion to 50°.

As shown in FIG. 5, it is a schematic diagram of installation of the torque sensor of the present invention.

The input coupling 16 is keyed to the output shaft of the reduction box and the torque sensor 5, and the output coupling 14 is keyed to the torque sensor 5 and the output shaft part; the input coupling 16 and the output coupling 14 are all tightened Screws eliminate loose play during key transmission, allowing rehabilitation equipment to operate more safely and efficiently.

The torque sensor adopts the electric measurement technology of the strain gauge, forms a strain bridge on the elastic shaft, and provides the power supply to the strain bridge to measure the electric signal of the elastic shaft torsion. After the strain signal is amplified, it becomes a frequency signal proportional to the torsional strain through voltage/frequency conversion.

Claims (10)

1. a kind of rehabilitation of anklebone system, it is characterised in that：Host computer connects electric machine controller, sends motor pattern instruction to electricity Machine controller, is controlled to electric machine controller；

Electric machine controller connection is arranged on the DC brushless motor (2) on mechanical driving device, exports to DC brushless motor (2) Control signal, control it；Receive simultaneously and be arranged at what inductance type pulse coder (1) on mechanical driving device fed back Motor position signal, closed-loop control is carried out to mechanical driving device.

2. rehabilitation of anklebone system according to claim 1, it is characterised in that：The mechanical driving device includes：

Inductance type pulse coder (1) coaxially connected DC brushless motor (2), other end connection electric machine controller, sends motor The control signal of controller, while generating corresponding pulse signal according to the rotation of DC brushless motor (2), and feeds back to motor Controller；

By inputting, shaft coupling (16) is coaxially connected to arrive reduction box (3) for torque sensor (5) one end, and reduction box (3) is coaxially connected DC brushless motor (2)；The other end is connected by exporting shaft coupling (14) coaxially connected output shaft, output shaft by connector (7) Pin pedal (9).

3. rehabilitation of anklebone system according to claim 2, it is characterised in that：The output shaft includes being fixed on bottom plate (10) bearing spider (6) on, sets the grease-enclosed type ball bearing of two low fat, two bearings in bearing spider (6) Inner ring carries out axial restraint by sleeve axial restraint, outer ring by the shaft shoulder and bearing (ball) cover (13).

4. rehabilitation of anklebone system according to claim 3, it is characterised in that：Also include angular transducer bearing (12) solid Due on bearing (ball) cover (13), shell (11) is connected through a screw thread angular transducer bearing (12), and angular transducer (8) is by outer Shell (11) fixes its outer ring, and inner ring is enclosed on axle, in real time the rotational angle of detection shaft.

5. rehabilitation of anklebone system according to claim 3, it is characterised in that：The bearing (ball) cover (13) is solid by screw thread It is scheduled on bearing spider (6), and interior setting limit sliding chutes, pin (15) cooperation with being fixedly installed on connector (7), it is used for The mechanical position limitation rotated to ankle-joint.

6. rehabilitation of anklebone system according to claim 1 or 2, it is characterised in that：The DC brushless motor (2) is to set The disc type DC brushless motor of Hall sensor is equipped with, current motor rotor-position, generation correspondence are detected by Hall sensor The exciting current in direction, driving DC brushless motor (2) is rotated.

7. rehabilitation of anklebone system according to claim 2, it is characterised in that：The torque sensor (5) is using strain Piece electric detecting technology.

8. rehabilitation of anklebone system according to claim 2, it is characterised in that：The input shaft coupling (16) and output connection Axle device (14) is flange coupling, is coupled by flat key with axle, and eliminate drive gap by holding screw.

9. rehabilitation of anklebone system according to claim 1, it is characterised in that：The motor position signal is：

Wherein, Θ_mFor motor corner, Θ_dAnkle-joint expects corner, and F is joint moment, and M is that inertial parameter, B are that damping, K are firm Degree, s is complex variable.

10. rehabilitation of anklebone system according to claim 5, it is characterised in that：The angle model that the limit sliding chutes are limited The dorsiflex hard-over enclosed for patient is 40 °, and plantar flexion hard-over is 50 °.