CN107374917A - Electronic body weight loss of weight mechanism and motion control method - Google Patents

Abstract

The invention discloses an electric weight loss mechanism and a motion control method. The electric weight loss mechanism includes a mechanical structure: used to support the human body and a movable chassis platform; a signal acquisition module: used to convert the pressure information of the human body into a voltage signal, convert the motor rotation into a voltage signal; upper computer processing module: used to receive the voltage signal and convert it into human body pressure data, and convert the motor voltage signal into a rotational speed; data analysis module: calculate the data obtained by the upper computer processing module Analyze and adjust the height of the support body and the speed of the required movement, and manually adjust the required state. The invention can help patients complete gait training, risk data, and recover walking ability conveniently and quickly.

Description

Electric weight loss mechanism and motion control method

【Technical field】

The invention relates to the design of the mechanical structure, the collection and processing of the signal, the motion control of the motor, the balance and stability of the whole device, the sensor technology, and specifically relates to the electric weight-reducing mechanism and the motion control method.

【Background technique】

With the aggravation of population aging and the improvement of people's living standards, patients with lower limb dysfunction caused by cardiovascular and cerebrovascular diseases are gradually increasing. Therefore, rehabilitation robots have become a research hotspot in the field of international robotics. Rehabilitation robots cover many disciplines such as rehabilitation medicine, mechatronics, biomechanics and robotics. Clinically, it is generally believed that early intervention of robot-assisted gait training (RAGT) in patients with stroke, spinal cord injury and traumatic brain injury can help them restore normal gait and restore walking ability. The RAGT system consists of a power platform, a weight reduction system, and a drive device connected to the leg or foot, which can provide external support for the patient's limbs and enable the patient to generate an electromechanical device for normal movement patterns when walking. Some hemiplegic patients are unable to stand on their own at the beginning of rehabilitation training due to insufficient support capacity of the lower limbs, so different weight loss methods are required for rehabilitation training.

The lower extremity rehabilitation training robot developed by researchers from Germany's Fraunhofer Automatic Robotics Research Center and Berlin Charitable Medical University has a weight reduction system, but it is difficult to apply to real life due to its large footprint; Xia The lower limb rehabilitation training robot developed by Wu Xin et al. uses only one steel wire rope for its weight reduction system, which is not good enough in safety and stability; the lower limb rehabilitation robot developed by Dong Yiming has certain guarantees in safety and stability, but it cannot Regulates the weight reduction capacity of the system. Based on this, there is an urgent need for a medical device that has good safety and stability and can be adapted to different stages of weight loss rehabilitation training.

【Content of invention】

In order to solve the problems existing in the prior art, the purpose of the present invention is to provide an electric weight loss mechanism and a motion control method. The present invention is used for lower limb rehabilitation training, can support the human body, automatically adjust the height of the human body from the ground, and automatically detect the load-bearing Strength, to quantify the body weight of the trainer.

To achieve the above object, the present invention adopts the following technical solutions:

An electric weight loss mechanism, including a signal acquisition module, a host computer processing module, a data analysis module, a suspension vest, a lifting motor and a chassis platform that can move freely. The armrest frame of the arm, the lifting motor is set on the chassis platform or the telescopic column, the output shaft of the lifting motor is connected with a wire rope reel, and a steel wire rope is wound on the wire rope reel, and the free end of the wire rope extends to the top of the telescopic column through the guide device. The free end is connected with a beam for hanging the suspension vest;

The bottom of the chassis platform is provided with an electric wheel hub for driving the chassis platform to move freely, the electric wheel hub is connected with a control handle, and the control handle is set on the armrest frame;

Both the controller of the lifting motor and the controller of the electric hub are connected to the upper computer processing module, which is connected to the signal acquisition module and the data analysis module respectively, and the signal acquisition module is connected to a pressure sensor for collecting the support force of the human body , A speed sensor used to collect the rotating speed of the lifting motor and the rotating speed of the electric hub.

The pressure sensor is arranged at the part where the sole of the foot is in contact with the ground, and is used to collect the pressure information of the human body on the supporting body.

The host computer processing module and the signal acquisition module are wirelessly connected through a wireless transmission module.

A data display module is connected to the upper computer processing module.

The chassis platform is a U-shaped structure, and the open end of the chassis platform can accommodate the running platform of the treadmill, so that the beam can be directly above the running platform of the treadmill.

The suspension vest is connected with the beam through a spring.

The motion control method of the electric body weight loss mechanism comprises the following steps:

(1) Collect the pressure information of the human body on its own support, the speed signal of the lifting motor and the speed signal of the electric hub;

(2) Convert the collected pressure information of the human body to its own support force, the speed signal of the lifting motor and the speed signal of the electric wheel hub into the pressure of the human body on its own support force, the speed of the lifting motor and the speed of the electric wheel hub;

(3) According to the pressure of the human body on its own supporting force obtained from the conversion in step (2), the speed of the lifting motor, combined with the actual gravity of the human body, the current weight reduction ratio is obtained, and the weight reduction ratio is compared with the set weight reduction ratio Compare, obtain the output torque that lifting motor needs; (4) control the rotation of lifting motor according to the output force that the lifting motor that the human body needs of step (3) calculates, adjust the height of suspension vest by the rotation of lifting motor;

(5) When it is detected that the pressure of the human body on its own supporting force is within the set range, the lifting motor is controlled to stop rotating.

Compared with the prior art, the present invention has the following beneficial effects:

The present invention respectively collects the pressure information of the human body's own support force, the speed signal of the lifting motor and the speed signal of the electric wheel hub through the pressure sensor, the speed sensor for collecting the rotating speed of the lifting motor, and the speed sensor for collecting the rotating speed of the electric hub, and then collects the above information through the signal acquisition module Output to the upper computer processing module, the upper computer processing module converts the pressure information of the human body on its own support, the speed signal of the lifting motor and the speed signal of the electric hub into the pressure of the human body on its own support, the speed of the lifting motor and the electric hub The data analysis module calculates the current weight reduction ratio based on the pressure information of the human body on its own support force and the speed signal of the lifting motor, combined with the actual gravity of the human body, and compares the weight reduction ratio with the set weight reduction ratio. After obtaining the output torque required by the lifting motor, the upper computer processing module also calculates the required rotation speed of the electric hub according to the rotation speed of the electric hub; the upper computer processing module controls the rotation of the lifting motor through the output torque required by the lifting motor, and through the lifting motor The rotation drives the wire rope disc to rotate to retract and release the wire rope, and further adjust the height of the suspension vest. The upper computer processing module controls the rotation speed of the electric hub according to the calculated rotation speed required by the electric hub. The controller controls the speed of the electric hub, so that the electric hub The reading reaches the required speed;

In the present invention, an electric wheel hub for driving the chassis platform to move freely is provided at the bottom of the chassis platform, a control handle is connected to the electric wheel hub, and the control handle is arranged on the armrest frame, so when the patient uses the electric weight loss mechanism of the present invention , can easily move by itself;

In the present invention, telescopic uprights for supporting the human body are arranged on the chassis platform, and through the flexibility of the telescopic uprights, the electric weight loss mechanism of the invention can adapt to patients of different heights and is convenient to use.

Further, the present invention uses the wireless transmission module to transmit the voltage signal obtained by the signal acquisition module to the upper computer processing module, so that the connection problem in the test can be reduced, the equipment can be simplified, and the interference of the test equipment to the walking process can be reduced.

Further, the present invention sets a data display module, which can firstly display the collected original human body pressure signals in real time, and display them flatly and differently; secondly, it can be set to reduce the weight, which is convenient to use; thirdly, it can display the speed of the human body during walking and pressure changes as well as control walking speed and direction.

Further, the chassis platform is a U-shaped structure, and the open end of the chassis platform can accommodate the running platform of the treadmill, so that the crossbeam can be placed directly above the treadmill platform, so the present invention can be used in conjunction with the treadmill, and can be used under the condition of natural weight loss. Next, long-term in-situ training on the treadmill.

【Description of drawings】

Fig. 1 is the constituent structure schematic diagram of electric weight reducing mechanism of the present invention;

Fig. 2 is a schematic diagram of the weight loss control flow chart of the present invention;

Fig. 3 is a schematic diagram of the overall motion control process of the present invention;

Fig. 4 is the signal acquisition circuit of the present invention;

Fig. 5 is a schematic diagram of the telescopic track of the telescopic column.

Among them, 1-chassis platform, 2-universal wheels, 3-electric hub, 4-battery pack, 5-wire rope, 6-telescopic column, 7-handrail frame, 8-beam, 9-track, 9-1-inner Pipe, 9-2-outer pipe, 9-3-positioning hole.

【detailed description】

The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

As shown in Fig. 1-Fig. 3, the electric weight reduction mechanism of the present invention comprises signal acquisition module, host computer processing module, data analysis module, suspension vest, lifting motor and chassis platform 1 that can move freely, chassis platform 1 is provided with a telescopic column 6 for supporting the human body and an armrest frame 7 for supporting the arms, the lifting motor is arranged on the chassis platform 1 or the telescopic column 6, the output shaft of the lifting motor is connected with a wire rope reel, and the wire rope reel is wound Steel wire rope 5 is arranged, and the free end of steel wire rope 5 extends to the top of telescopic column 6 through guiding device, and the free end of steel wire rope 5 is connected with beam 8 for hanging suspension vest, and suspension suspension vest is connected with cross beam 8 by spring;

The bottom of the chassis platform 1 is provided with an electric hub 3 for driving the chassis platform 1 to move freely, the electric hub 3 is connected with a control handle, and the control handle is arranged on the armrest frame 7;

Both the controller of the lifting motor and the controller of the electric hub 3 are connected with the upper computer processing module, and the upper computer processing module is respectively connected with the signal acquisition module and the data analysis module. Sensors, speed sensors used to collect the rotating speed of the lifting motor and the rotating speed of the electric hub 3; the pressure sensor is arranged at the part where the sole of the foot is in contact with the ground, and is used to collect the pressure information of the human body on the support body.

As shown in Figure 1, the chassis platform 1 is a U-shaped structure, and the open end of the chassis platform 1 can accommodate the running platform of the treadmill, so that the beam 8 can be directly above the running platform of the treadmill.

The motion control method of the electric body weight loss mechanism of the present invention, in conjunction with Fig. 2 and Fig. 3, comprises the following steps:

(1) Collect the pressure information of the human body on its own support force, the speed signal of the lifting motor and the speed signal of the electric hub 3;

(2) Convert the collected pressure information of the human body to its own supporting force, the rotating speed signal of the lifting motor and the rotating speed signal of the electric hub 3 into the pressure of the human body on its own supporting force, the rotating speed of the lifting motor and the rotating speed of the electric hub 3;

(3) According to the pressure of the human body on its own support and the speed of the lifting motor obtained from the conversion in step (2), combined with the actual gravity of the human body, the current weight reduction ratio is obtained, and the weight reduction ratio is compared with the set weight reduction ratio Compare to get the output torque required by the lifting motor;

(4) control the rotation of the lifting motor according to the required output torque of the lifting motor calculated in step (3), and adjust the height of the suspension vest by the rotation of the lifting motor;

(5) When it is detected that the pressure of the human body on its own supporting force is within the set range, the lifting motor is controlled to stop rotating.

Example

The electric body weight loss mechanism of the present invention comprises a mechanical structure part, and the mechanical structure part comprises:

Used to support the human body and a movable chassis platform 1; signal acquisition module: as shown in Figure 4, it is used to convert the pressure information of the human body to its own support force into a voltage signal, and convert the rotation signal of the motor rotation into a voltage signal, the label S1 is connected to the pressure sensor, the sensor is connected to another port-3.3V voltage, and the label PA.0 is connected to the AD acquisition terminal of the I/O port of the processor; the upper computer processing module: used to receive the piezoelectric signal and convert the above The three kinds of piezoelectric signals are respectively converted into the pressure data of the human body on the support, and the voltage signal of the motor is converted into the rotational speed; the data analysis module: calculates, analyzes and adjusts the output of the lifting motor for the pressure data and rotational speed data obtained by the upper computer processing module To change the height of the support body and the speed at which the chassis platform needs to move, and the required state can be adjusted by manually operating the control handle.

The system also includes a wireless transmission module: used to transmit the voltage signal obtained by the signal acquisition module to the upper computer processing module through Bluetooth; the movable chassis platform is an electric trolley based on the electric hub, and the electric trolley is the base of the whole mechanism, and the chassis platform has an opening The end is the front end, and the two ends of the opening end are respectively provided with a universal wheel, and the end opposite to the opening end on the chassis platform is the rear end, and the electric hub is set at the rear end as the rear wheel; the electric hub is powered by a 24v battery, driven by The circuit is connected to the hub motor, and the control unit of the electric hub can indirectly control the rotation speed of the electric wheel by controlling the disconnection of the drive circuit; the data display module can display the pressure information, speed information and direction information obtained by the upper computer processing module in real time;

The selection of steel wire rope of the present invention, according to empirical formula F≤50/K

In the formula, F(kg) is the breaking force of the steel wire rope, K is the safety factor, K=4; D(mm) is the diameter of the steel wire rope; when F=150kg, D≥3.46mm, therefore, this design chooses the round strand steel wire rope is 6×7, select D=4mm, and the end of the wire rope is connected with an open socket;

For the selection of springs, it is assumed that the weight of the patient is 150kg, so the maximum tension that each spring can withstand should exceed 750N. According to the data in the mechanical design manual, the diameter of the selected spring is d=6mm, the middle diameter of the spring is D=65mm, and the allowable shear stress τ _p ＝585MPa, the maximum tensile force it can withstand is 796N, the number of spring coils is n＝15, the spring stiffness k＝3N/mm, and the form of the tension spring hook is LVII type;

Considering the different heights of patients, it is assumed that the height of the patient is 152-188cm, the variation range is 36cm, and when the weight loss mode is 30%, the patient is 150kg, and the spring deformation is 25cm, so the length of the track of the telescopic column (see Figure 5) and The expansion and contraction of the control handle must be greater than 51cm. The track 9 of the telescopic column includes an outer tube 9-2 arranged at the bottom, an inner tube 9-1 is inserted into the upper end of the outer tube 9-2, and there is a gap between the outer wall of the inner tube 9-1 and the inner wall of the outer tube 9-2 Cooperate, the pipe wall of inner pipe 9-1 and outer pipe 9-2 is provided with several groups of positioning holes 9-3 for positioning along their radial direction, and inner pipe 9-1 and inner pipe 9-1 can be made to be able to make by setting latch in the positioning hole. The outer tube 9-2 is relatively fixed, thereby realizing the adjustment of the height of the telescopic column, so as to be suitable for patients of different heights and improve the universality of the equipment.

Select the control handle, the control handle has the advantages of small size, high precision, complete synchronization, and good self-locking performance, and also provides a PLC access port to achieve real-time control of the process. In order to ensure that the control handle can work normally, during use by patients, The range of manual operation is limited, and for safety reasons, in order to prevent accidental injuries to the patient due to insufficient tensile strength of the handle and broken handle during use, the tensile strength must be greater than the patient's weight, that is,

F=mg=150×10=1500N

Combined with the above analysis, the present invention selects the stroke of the control handle as 600mm, and the parameters of the selected control handle are input voltage 24V, maximum load 2000N, and speed 13mm/s.

Select the pressure sensor, the patient with a weight of 150kg, in the 30% weight loss mode, receives a tensile force of 450N, choose the standard with high measurement accuracy, good stability, small temperature drift, good output symmetry, and compact structure. Flexiforce sensor, its measuring range is 0～750N.

The voltage of the electric hub is 24V, the power is 350W, the diameter of the tire is 20cm, the width of the tire is 5cm, and the speed is 28 kilometers per hour. The driving device of the electric hub is a 24V motor driver, and the battery pack 4 is connected to the 24V motor driver. The required energy supply is 24V Lithium battery, the upper computer can control the speed of the electric wheel and the direction of movement of the overall system; the lifting motor can reach the torque that pulls up the human body, and can adjust the speed in real time and quickly. The formula for the speed and torque of the lifting motor is as follows:

Motor power: P=1.732×U×I×cosφ, U is the voltage, the unit is V, I is the current, the unit is A;

Motor torque: T=9549×P/n;

Motor power torque＝9550×output power/output speed

Torque=9550×output power/output speed.

In the formula, P is the power kW, T is the torque N·m, and n is the speed r/min.

When the electric weight loss mechanism of the present invention is in use, the method is as follows:

Step 1: Collect the pressure information of the human body on the support to support itself;

Step 2: Calculate and analyze the collected pressure information to obtain the pressure data of the human body, and adjust the pulling force of the support structure on the human body according to the pressure information. The pulling force control depends on the torque of the motor to achieve the body weight pressure that can be supported by the legs of the human body;

Step 3: The chassis platform starts to move forward, and the required forward speed can be adjusted through the control handle. During the exercise, the pressure of the human body is detected, and the pulling force of the support body to the human body is adjusted in real time according to the pressure information, so as to achieve real-time weight loss during the exercise. Effect.

In step 1, two pressure sensors are installed on the part where the sole of the foot is in contact with the ground to collect the pressure information of the human body on the support body.

Compared with the prior art, the present invention has the following beneficial technical effects:

The system of the present invention uses a pressure sensor to detect the pressure information of the human body, then uses the signal acquisition module to convert the pressure information into a voltage signal, uses the upper computer processing module to receive the voltage signal and converts it into pressure information, and uses the data analysis module to process the upper computer. The obtained pressure information is calculated and analyzed to obtain the pressure of the human body, and the pressure data is used to compare the required weight loss. When the pressure data exceeds the normal setting data range, the weight loss effect can be achieved by adjusting the tension, which can be achieved quickly and in real time. Adjust the weight loss effect to ensure a certain pressure between the human body and the ground, protect the tester's physical endurance, and reduce the secondary injury suffered by the user.

The invention adopts a faster lifting motor as the power source of the pulling force, and the adjustment speed is faster than artificial adjustment, and the height efficiency of the artificial adjustment of the support body is slow, and it is easy to make a wrong estimation of the pressure of the human body, thereby causing damage to the human body, and the motor can pass through it well. Control to achieve the required weight reduction pressure, so as to protect the user, adjust the initial state more quickly, and control the torque of the motor in real time during exercise, so as to ensure that the weight loss remains unchanged in different states.

The present invention adopts the electric wheel hub, so the whole device can be moved conveniently. Compared with the previous devices that cannot move automatically, the present invention can artificially control the speed and trajectory of the movement, set the weight loss according to the weight of the user, and automatically adjust during the movement Pulling force, keeping the weight loss unchanged, to achieve a better effect of use.

The invention can reduce the user's wearing burden and improve flexibility. The weight-reducing support frame can be adjusted in real time, and can realize weight-reducing training for people of different heights and weights. It can be used by different fat and thin people. There are electric wheels at the bottom of the whole device, which can adjust the required walking speed. It can be used by different types of trainers, and it is also convenient to carry and use for long distances. Large-capacity batteries are more suitable for long-term use. The design of the suspension vest is based on the inverted triangle shape of the human body, which can evenly distribute the force around the human torso. The control system can monitor the trainer's walking speed in real time, control the direction of rotation and the stability of weight loss, and is more convenient and comfortable to use.

At the same time, the automatic control of the overall platform can move forward, backward and turn as a whole, and adjust the speed of movement, and automatically avoid obstacles. It can also cooperate with the treadmill to enable patients to train at fixed points during the suspension weight loss process. It is a convenient and convenient rehabilitation electric training equipment.

Stroke patients may lose many abilities such as intelligence, perception and movement due to damage to brain cells. However, as an organism, certain parts of the human body have the ability to regain their shape through regeneration and their function through retraining, and this includes the brain and spinal cord. Based on this hypothesis, gait rehabilitation programs are developed to allow patients in this category to rediscover their mobility and stimulate functional recovery from spinal cord injuries through repetitive actions;

Sitting in a wheelchair or bed for a long time during the recovery period weakens the ability of the leg muscles to support one's own weight, and the therapist must assist the patient in the rehabilitation training, which consumes a lot of time and energy.

The electric weight loss mechanism of the present invention can assist doctors in recovery training for disabled patients, fills up many loopholes in clinical rehabilitation and exercise treatment, and is expected to replace manual treatment in the near future. Practice, the exploration and research of rehabilitation robots have brought medicine and engineering closer, opened up a broader vision for the development of human medical care, and have important practical value for the future development of human beings.

When rehabilitation patients use the electric weight loss mechanism for rehabilitation training, the patients need to wear auxiliary equipment such as suspension vests in advance, and use wheelchairs and other tools to bring the rehabilitation patients to the predetermined position, that is, the position below the middle beam and facing the column beam of the mechanism; Then connect the steel wire rope, the suspension vest and the connection line between the pressure sensor and the controller, measure the support force of the human body to itself through the pressure sensor placed at the contact point between the sole of the foot and the ground, convert it into a voltage signal, and transmit the voltage signal through the wireless communication module To the upper computer, through the upper computer processing module and the data analysis and processing module, the pressure information and the control signal of the motor are obtained. Heavy; when the rehabilitation patient can stand up with two feet with the help of the mechanism, with the help of others, he can further rotate 180° to the position facing away from the beam column of the mechanism; and then through the control of the handle in the mechanism, the hub motor can be controlled to achieve the movement of the mechanism Assist in rehabilitation training. The mechanism can also cooperate with the treadmill to achieve the purpose of fixed-point training.

Claims (7)

1. The electric weight loss mechanism is characterized in that it comprises a signal acquisition module, a host computer processing module, a data analysis module, a suspension vest, a lifting motor and a freely movable chassis platform (1), on which the chassis platform (1) A telescopic column (6) for supporting the human body and an armrest frame (7) for supporting the arms are provided, the lifting motor is arranged on the chassis platform (1) or the telescopic column (6), and the output shaft of the lifting motor is connected with a wire rope reel A wire rope (5) is wound on the wire rope reel, and the free end of the wire rope (5) extends to the top of the telescopic column (6) through a guide device, and the free end of the wire rope (5) is connected with a crossbeam (8) for hanging a suspension vest ); The bottom of the chassis platform (1) is provided with an electric wheel hub (3) for driving the chassis platform (1) to move freely, the electric wheel hub (3) is connected with a control handle, and the control handle is arranged on the armrest frame (7); Both the controller of the lifting motor and the controller of the electric hub (3) are connected with the upper computer processing module, and the upper computer processing module is connected with the signal acquisition module and the data analysis module respectively, and the signal acquisition module is connected with a device for collecting the support force of the human body against itself. The pressure sensor, the speed sensor used to collect the rotation speed of the lifting motor and the rotation speed of the electric hub (3). 2 . The electric weight loss mechanism according to claim 1 , wherein the pressure sensor is arranged at the part where the sole of the foot is in contact with the ground, and is used to collect information about the pressure of the human body on the supporting body. 3 . 3. The electric weight loss mechanism according to claim 1, characterized in that, the host computer processing module and the signal acquisition module are wirelessly connected through a wireless transmission module. 4. The electric body weight reduction mechanism according to claim 1, wherein a data display module is connected to the host computer processing module. 5. The electric weight loss mechanism according to claim 1, characterized in that, the chassis platform (1) is a U-shaped structure, and the open end of the chassis platform (1) can accommodate the treadmill of the treadmill, so that the crossbeam (8) It can be directly above the treadmill platform. 6. The electric weight loss mechanism according to claim 1, characterized in that, the suspension vest is connected to the beam (8) through a spring. 7. The control method based on the electric body weight loss mechanism of claim, is characterized in that, comprises the steps: (1) Collect the pressure information of the human body on its own support force, the speed signal of the lifting motor and the speed signal of the electric hub (3); (2) The collected pressure information of the human body on its own support, the speed signal of the lifting motor and the speed signal of the electric hub (3) are respectively converted into the pressure of the human body on its own support, the speed of the lifting motor and the speed signal of the electric hub (3) ) speed; (3) According to the pressure of the human body on its own support and the speed of the lifting motor obtained from the conversion in step (2), combined with the actual gravity of the human body, the current weight reduction ratio is obtained, and the weight reduction ratio is compared with the set weight reduction ratio Compare, obtain the output torque that lifting motor needs; (4) control the rotation of lifting motor by the output torque that the lifting motor that calculates according to step (3) needs, adjust the height of suspension vest by the rotation of lifting motor; (5) When it is detected that the pressure of the human body on its own supporting force is within the set range, the lifting motor is controlled to stop rotating.