TWI730461B - Driving system for an axillary power device - Google Patents

Abstract

A driving system for an axillary power device is provided to overcome the problem where the actions of the conventional axillary power device are not continuous and the timing in outputting the force is not accurate. The driving system for the axillary power device includes a power unit configured to provide auxiliary power to assist a user’s movement, a displacement sensing unit mounted on the power unit and configured to monitor the power unit and generate a position signal, a myoelectricity sensing module including a plurality of electrode pasters respectively adhered to a plurality of muscle clusters of the user and generating a myoelectricity signal, and a processing unit coupled with the power unit, the displacement sensing unit and the myoelectricity sensing module and generating a control signal based on the position signal and the myoelectricity signal. The power unit provides the auxiliary power based on the control signal.

Description

Drive control system of power assist device

The present invention relates to a drive technology of a power device, in particular to a drive control system of a power assist device that provides instant and stable power assistance.

Power-Assisted Device (Power-Assisted Device) can help the elderly, people with spinal cord injury and rehabilitation patients with mobility impairments to increase mobility, improve rehabilitation efficiency, and reduce weight-bearing output. Most of the conventional power assist devices are joint-type mechanisms combined with servo motors, and are assembled on movable parts of the human body such as limbs or trunk, and can provide auxiliary power according to the degree of freedom of the body's joints. The conventional power assist device can be Orthotics, which is used to assist people with impaired muscle function to recover their mobility; it can also be Exoskeleton, which is used to enhance the wearer’s movement speed, weight and endurance. And so on athletic ability.

The above-mentioned conventional power assist device needs to collect the data of the user's force status through the force sensor. By analyzing the user's activity, the power assist device can drive and control the appropriate auxiliary power. However, it is installed The force sensor will increase the extra load and require a larger installation space, which leads to problems such as low power assist efficiency and increased installation cost. In addition, the force sensor must be measured in the correct position to reflect the user’s real activities Status, which increases the difficulty of installing the force sensor.

In addition, the conventional power assist device can also drive and control the auxiliary power according to the force estimation method. However, the force estimation system analyzes the calculation result of the displacement change, and the user is applying force. Displacement does not necessarily occur during the process, which results in the user being unable to get the support of auxiliary power at the stage when the user starts to output or pauses and continues to output, so that the operation of the conventional power assist device is discontinuous or the timing of the output is incorrect, and the power is reduced. The working efficiency of the auxiliary device may even cause sports injuries to the user.

In view of this, it is indeed necessary to improve the drive control of the conventional power assist device.

In order to solve the above-mentioned problems, the purpose of the present invention is to provide a drive control system of a power assist device, which provides immediate, stable and continuous auxiliary power.

The second objective of the present invention is to provide a drive control system of the power assist device to improve the working efficiency of the power assist device.

Another object of the present invention is to provide a drive control system for a power assist device to improve the operation safety of the power assist device.

The elements and components described in the full text of the present invention use the quantifiers "one" or "one" for convenience and to provide the general meaning of the scope of the present invention; in the present invention, it should be construed as including one or at least one, and single The concept of also includes the plural, unless it clearly implies other meanings.

The drive control system of the power assist device of the present invention includes: a power unit for driving a power assist device, the power assist device assists a user to exercise; a displacement sensing unit located in the power unit, the displacement sensing unit The measuring unit is used to monitor the power unit and output a position signal; a myoelectric measuring module has several electrode patches attached to the user’s motor muscle groups, and the myoelectric measuring module outputs one Myoelectric signal; and a processing unit, respectively coupled and connected to the power unit, the displacement sensor and the myoelectric sensing module, the processing unit according to the position The setting signal and the myoelectric signal generate a control signal, and the power unit drives the power assist device according to the control signal. The power unit alternately outputs an auxiliary torque and a displacement torque. The auxiliary torque and the displacement torque are in the alternating process The flexible switching is made in a way that one torque gradually increases and the other torque decreases gradually.

Accordingly, the drive control system of the power assist device of the present invention continuously monitors the use status of the power assist device through the displacement sensing unit and the myoelectric sensing module, and feeds back the position signal and the myoelectric signal to control the assist The power output can provide immediate and continuous auxiliary power to avoid the auxiliary power stop or instantaneous output. It has the functions of improving the working efficiency of the power auxiliary device, improving the safety of operation and improving the user experience.

Wherein, the power unit is located on the rotating shaft of the power assist device, and the power assist device has a power rod connected to the power unit, and the power rod is driven to rotate by the power unit. In this way, the power rod system can drive the limbs or torso of the user, and has the effect of providing power to assist in exercise.

Wherein, the power rod rotates in a working range, and the working range includes an auxiliary zone and two buffer zones located on both sides of the auxiliary zone. In this way, since the human body cannot rotate 360 degrees in joint motion, the working range conforms to the joint motion range to limit the motion of the power rod within the movable range of the joint, which has the effect of avoiding injury to the user caused by auxiliary power.

Wherein, the displacement sensor measures the rotation change of the power unit, and recognizes the position of the power rod in the auxiliary section or between the two buffer zones. In this way, the displacement sensor can monitor the operation status of the power assist device, and has the function of assisting in force estimation and feedback adjustment of output.

Wherein, when the power rod is located in the auxiliary zone, the processing unit adjusts the control signal according to the position signal, so that the power unit outputs auxiliary power corresponding to the position signal. In this way, it has the effect of providing auxiliary power that meets the user's action requirements.

Wherein, when the power rod is located between the buffer zone, the processing unit limits the power The output of the unit. In this way, the system has the effect of preventing the power rod from exceeding the working range.

Wherein, the auxiliary torque is proportional to the product of the myoelectric signal and an auxiliary ratio. When the position signal does not appear, the auxiliary ratio maintains a certain value. In this way, the power assist device system can still produce stable assistance when it is not moving, and has the effect of providing auxiliary power for continuous output work such as handling and support.

Wherein, after the position signal appears, the auxiliary ratio gradually attenuates to zero, and when the position signal decreases, the auxiliary ratio gradually returns to the constant value. In this way, the power assist device can provide assistance according to changes in motion during displacement, and has the effect of improving the immediacy and smoothness of auxiliary power.

The displacement torque is adjusted according to the information content of the position signal, and the position signal includes the displacement direction, distance, position and speed of the power unit. In this way, the position signal can be used for power estimation calculation, which has the effect of improving the accuracy of auxiliary power and working efficiency.

1: Power unit

2: Displacement sensing unit

3: Muscle induction measurement module

31: Electrode patch

4: Processing unit

S: Power assist device

U: User

P: Position signal

M: exercise muscle group

E: EMG signal

C: Control signal

R: Power rod

V1: Auxiliary interval

V2: between buffers

A: Auxiliary ratio

T1: auxiliary torque

T2: displacement torque

[Figure 1] A system block diagram of a preferred embodiment of the present invention.

[Figure 2] A diagram of the operation mode of a power assist device according to a preferred embodiment of the present invention.

[Figure 3a] A time variation diagram of a muscle electrical signal according to a preferred embodiment of the present invention.

[Picture 3b] The position signal and auxiliary ratio time change diagram corresponding to the picture 3a.

[Figure 3c] Corresponds to the time change diagram of the output torque shown in Figure 3a.

In order to make the above and other objectives, features and advantages of the present invention more comprehensible, the following describes the preferred embodiments of the present invention in conjunction with the accompanying drawings in detail as follows: Please refer to Figure 1, which is a preferred embodiment of the drive control system of the power assist device of the present invention, which includes a power unit 1, a displacement sensing unit 2, a myoelectric sensing module 3, and a processing unit 4. The power unit 1, the displacement sensor 2 and the myoelectric sensing module 3 are respectively coupled to the processing unit 4, and the displacement sensor 2 is located in the power unit 1.

The power unit 1 is used to drive a power assist device S. The power assist device S may be a torque device and fitted to the limbs or torso of a user U. The power unit 1 may be a motor actuator for supporting or pushing the aforementioned The torque device enables the output torque of the power unit 1 to assist the user U to exercise.

The displacement sensing unit 2 is used to monitor the activity status of the power unit 1, and the displacement sensing unit 2 outputs a position signal P. The position signal P includes the output direction and the displacement interval of the power unit 1. The displacement The sensing unit 2 can be an encoder of the above-mentioned motor actuator. The displacement sensing unit 2 encodes the torsion angle of the corresponding motor, and can increase or decrease the number to indicate the rotation direction of the power unit 1. Distance, position and speed.

The myoelectric sensing module 3 is made up of a plurality of electrode patches 31 adhered to the motor muscle groups M of the user U, and the myoelectric sensing module 1 records the plurality of muscle groups M through the electrode patches 31 The electrical signal generated by the contraction of the exercise muscle group M is analyzed and integrated into an electromyography (Electromyography, EMG). The myoelectric measurement module 1 can output an electromyographic signal E, which is based on The change in voltage amplitude indicates the exercise output of the user U.

The processing unit 4 generates a control signal C according to the position signal P and the myoelectric signal E. The processing unit 4 can also switch between the position signal P and the myoelectric signal E by fuzzy theory, so that the The power unit 1 adjusts the direction and magnitude of the power output according to the control signal C, which can drive the power assist device S to provide thrust with moderate power and the correct direction, and to assist the user U to move in real time and steadily.

Please refer to Figure 2, which is a preferred embodiment of the power assist of the present invention According to the aforementioned structure, the power unit 1 can be located on the shaft of the power assist device S, and the power unit 1 is connected to a power rod R, which is driven by the power unit 1 to rotate Within a working range, the working range includes an auxiliary interval V1 and two buffer spaces V2 located on both sides of the auxiliary interval V1. In addition, the displacement sensor 2 may be located in the power unit 1. The displacement sensor 2 Measure the rotation change of the power unit 1, and also identify the position of the power rod R in the auxiliary interval V1 or the second buffer zone V2.

Please refer to Figures 1 and 2, the power assist device S is assembled on any joint of the user U, the power unit 1 drives the power rod R according to the control signal C, so that the power rod R can be synchronized when rotating The limbs or torso of the user U are driven to move, wherein the working range of the power rod R preferably conforms to the movable angle of the joint, which can prevent the power assist device S from improperly outputting and causing the user U to be injured. In addition, when the power rod R is located in the auxiliary interval V1, the displacement sensor 2 outputs the position signal P, so that the processing unit 4 adjusts the control signal C according to the change of the position signal P, and the power unit 1 can The auxiliary power corresponding to the position signal P is output; and when the power rod R is located in the buffer zone V2, the processing unit 4 uses the control signal C to limit the output of the power unit 1 to prevent the power rod R from being in the buffer zone. The interval V2 receives an instantaneous force and exceeds the working range.

Please refer to Figures 3a to 3c, which are the comparison diagrams of the time change of the position signal P and the electromyographic signal E converted into the output torque force according to the present invention. As shown in Figure 3a, the curve of the electromyographic signal E It represents the change of output; as shown in Figure 3b, an auxiliary ratio A maintains a certain value when the position signal P does not appear. After the position signal P appears, the auxiliary ratio A gradually decays to zero, and, When the position signal P weakens, the auxiliary ratio A gradually returns to the fixed value; as shown in Figure 3c, an auxiliary torque T1 and a displacement torque T2 jointly form an output torque force, where the auxiliary torque T1 is proportional to The product of the myoelectric signal E and the auxiliary ratio A, and the displacement torque T2 are adjusted according to the information content of the position signal P, which includes the power unit 1 In this way, the auxiliary torque T1 and the displacement torque T2 can alternately appear, and the effect of flexible switching can be achieved by gradually increasing or decreasing during the alternating process. Please refer to the In Figure 3a, the curve change of the EMG signal E shows that with the power assistance of the auxiliary torque T1 and the displacement torque T2, the muscle output condition has gradually changed from unstable and high burden at the beginning to gentle and weaker. The power output can improve the power switching process and provide immediate and stable auxiliary power.

In summary, the drive control system of the power assist device of the present invention continuously monitors the usage status of the power assist device through the displacement sensing unit and the myoelectric sensor module, and feeds back the position signal and the electromyographic signal to Controlling the output of auxiliary power can provide immediate and continuous auxiliary power. In addition, by using the position signal and the EMG signal by flexible switching, the auxiliary power can be prevented from stopping or instantaneous output, and it can improve the work of the power assist device. Efficiency, improve operational safety and improve user experience and other functions.

Although the present invention has been disclosed using the above-mentioned preferred embodiments, it is not intended to limit the present invention. Anyone who is familiar with the art without departing from the spirit and scope of the present invention may make various changes and modifications relative to the above-mentioned embodiments. The technical scope of the invention is protected. Therefore, the scope of protection of the invention shall be subject to the scope of the attached patent application.

1: Power unit

2: Displacement sensing unit

3: Muscle induction measurement module

31: Electrode patch

4: Processing unit

S: Power assist device

U: User

P: Position signal

M: exercise muscle group

E: EMG signal

C: Control signal

Claims (9)

A drive control system for a power assist device includes: a power unit for driving a power assist device, the power assist device assists a user to exercise; a displacement sensing unit located in the power unit, the displacement sensing unit Used to monitor the power unit and output a position signal; a myoelectric sensor module with several electrode patches attached to the user's motor muscle groups, and the myoelectric sensor module outputs a myoelectric signal And a processing unit respectively coupled to the power unit, the displacement sensor and the myoelectric sensing module, the processing unit generates a control signal according to the position signal and the myoelectric signal, and the power unit according to the The control signal drives the power assist device, and the power unit alternately outputs an assist torque and a displacement torque. The assist torque and the displacement torque are flexibly switched in a way that one torque gradually increases and the other torque gradually decreases during the alternating process. For example, the drive control system of the power assist device of claim 1, wherein the power unit is located on the rotating shaft of the power assist device, the power assist device has a power rod connected to the power unit, and the power rod is driven to rotate by the power unit. For example, the drive control system of the power assist device of claim 2, wherein the power rod rotates within a working range, and the working range includes an auxiliary section and two buffer zones located on both sides of the auxiliary section. For example, the drive control system of the power assist device of claim 3, wherein the displacement sensor measures the rotation change of the power unit and recognizes the position of the power rod in the auxiliary section or between the two buffer zones. For example, the drive control system of the power assist device of claim 3, wherein, when the power rod is located in the assist zone, the processing unit adjusts the control signal according to the position signal to make The power unit outputs auxiliary power corresponding to the position signal. For example, the drive control system of the power assist device of claim 3, wherein when the power rod is located between the buffer zone, the processing unit limits the output of the power unit. For example, the drive control system of the power assist device of claim 1, wherein the assist torque is proportional to the product of the myoelectric signal and an assist ratio. When the position signal does not appear, the assist ratio maintains a certain value. For example, the drive control system of the power assist device of claim 7, wherein after the position signal appears, the assist ratio gradually decays to zero, and when the position signal decreases, the assist ratio gradually returns to the fixed value. For example, the drive control system of the power assist device of claim 1, wherein the displacement torque is adjusted according to the information content of the position signal, and the position signal includes the displacement direction, distance, position and speed of the power unit.

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