KR102228527B1 - Method and apparatus for controlling wearable robot - Google Patents

Abstract

The present invention relates to a control method and apparatus for a wearable robot, _{a position control step of receiving a position vector value (q) and a position command value (q d} ) of the robot and outputting a position control value (u), the position control An external force observing step of receiving a value (u) and observing an external force to output an external force compensation value, receiving the position control value (u) and double-integrating it through an integral gain (ρ) to obtain the position command value (q _d ). And a double integration step of feeding back, and a switch step of selectively providing the position control value u output in the position control step to the double integration step according to a state transition condition. Accordingly, the present invention can support muscle strength according to the intention of the wearer's motion by receiving feedback on only the joint position information of the robot, thereby simplifying the system and reducing the cost of construction, and can be universally applied to a general upper limb exoskeleton robot platform.

Description

Control method and device for wearable robot {METHOD AND APPARATUS FOR CONTROLLING WEARABLE ROBOT}

The present invention relates to a control method and apparatus for a wearable robot, and more particularly, a control method and apparatus for a wearable robot capable of assisting various activities without using a separate sensor for determining the intention of the wearer. It is about.

In modern society, robots are widely used to prevent injuries and improve efficiency of workers in extreme environments, precision work, and industrial sites that require simple work, as well as medical diagnosis, rehabilitation/physical therapy, and muscle support using the impedance measurement of the body. It is also widely used in the medical field for purposes, etc.

Robots used for the purpose of supporting muscle strength are generally used by being worn on a person's hand, arm, or leg. Such a wearable robot refers to a robot that senses the movement of a human arm or leg and moves a robot arm or leg equipped with an actuator to assist human movement and amplify power.

In general, a wearable robot detects a user's intention to move through various sensors and operates an actuator such as a motor installed in a joint to support the wearer's muscle strength. That is, the movement of the wearer is transmitted to the robot, and the movement intention of the wearer is determined by detecting the force transmitted to the robot and the corresponding movement through various sensors (EMG sensor, force/torque sensor, etc.) installed in the robot. In addition, the robot uses the result of determining the wearer's intention to drive an actuator provided in the joint, thereby supporting muscle strength to match the wearer's movement.

However, there is a problem in that a sensor arrangement, an increase in cost and volume, and a complicated signal processing process are required to grasp the operation intention of the wearer.

Accordingly, in a technical field related to a wearable robot, there is a need for a control method capable of supporting various activities intended by the wearer while simplifying the system to reduce the volume and reduce the construction cost.

Korean Patent Laid-Open Publication No. 10-2017-0128712 (2017.11.23) supports the back of the wearer and is connected to the body part equipped with the drive motor, the lower body of the wearer, and is connected to the drive motor and the wire part, and measures the rotation angle. A method of controlling a wearable robot comprising a leg portion having a rotation angle sensor unit, comprising: a confirmation step of receiving a measurement value for a rotation angle measured by a rotation angle sensor unit and checking whether the measured value reaches a preset reference value; And a driving step of providing an assistive force by pulling the wire portion by operating the driving motor at a predetermined auxiliary torque value according to the angle at which the wearer bends the waist when the measured value reaches the reference value. Accordingly, a wearable robot and a control method of the wearable robot are introduced that allow a smooth movement to be performed according to the movement and work situation of the wearer by variably providing assistive power.

Korean Patent Registration No. 10-1766033 (2017.08.01) is a method for determining user intention of a wearable robot to determine the user's robot driving intention when controlling a wearable robot using a wire driving method. A calculation step of continuously measuring and calculating an instantaneous tension change rate using the measured tension data; A derivation step of calculating a user intention value based on the instantaneous tension change rate; A drive determination step of determining whether to drive the robot based on a comparison result of comparing the user intention value and a preset motion intention sensitivity; And in the drive determination step, it is determined to drive the robot, and while the robot is being driven, the user intention value changes from a value greater than the motion intention sensitivity to a smaller value? Disclosed is a method and system for determining a user intention of a wearable robot having a wire-driven joint linkage mechanism including; determining an abnormal motion of stopping the driving of the robot when it fluctuates from a smaller value to a larger value.

Korean Patent Publication No. 10-2017-0128712 (2017.11.23) Korean Patent Registration No. 10-1766033 (2017.08.01)

An embodiment of the present invention is to provide a control method and apparatus for a wearable robot that can assist various activities without using a separate sensor for determining the intention of the wearer.

An embodiment of the present invention is to provide a control method and apparatus for a wearable robot in which the robot can complete the motion when the wearer applies only a force to perform an intended motion without the influence of an external force.

In one embodiment of the present invention, the robot cannot move by activating the position control, but the applied external force can be compensated, and the actuator output force to compensate for the external force by deactivating the position control is maintained, and the force of the wearer is Thus, it is intended to provide a control method and an apparatus for a wearable robot in which the robot can move.

Among the embodiments, a control method for a wearable robot receives a position vector value (q) and a position command value (q _d ) of the robot, calculates a position error (e), and calculates a position error (e) based on the position error (e), and based on the position error (e), the PID (Proportation A position control step of outputting a position control value (u) for controlling the movement position of the robot to remove the position error (e) by performing integral derivative) control, and receiving the position control value (u) The external force observation step of integrating until the control value (u) reaches the external force (Fe) and applying a gain (γ) to observe the external force, and subtracting the observed external force value from the position control value (u) to compensate for the external force. An external force compensation step of outputting the actuator force command value (τ _d ) including the force to be performed, the position control value (u) is received and double-integrated through the integral gain (ρ) to obtain the position command value (q _d ). And a double integration step of feeding back, and a switch step of selectively providing the position control value u output in the position control step to the double integration step according to a state transition condition.

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In the double integration step, when the switch step is in the "ON" state, double integration is performed on the position control value (u) to provide the position command value (q _d ) to the position control step to provide position control. Can be disabled.

The switch step automatically becomes a "turn-off" state for compensation of an external force acting on the robot, and a "turn-on" state for the operation of the robot by a force applied by a user to the robot after external force compensation. Can be controlled by

In the switch step, an external force is compensated in an "OFF" state, so that the output force of the actuator of the robot is in equilibrium with the external force, and then, when a user applies a force to move, it may transition to an "ON" state.

In the "ON" state, when the operation by the user's force is completed and the speed of the end of the robot converges to "0", or the operation is stopped due to a sudden change in the force acting on the robot, the switch step is "off". It can be transitioned to "(OFF)" state.

Among the embodiments, the control method for the wearable robot is a static step of activating the position control of the robot to fix the posture of the robot and compensating for an external force applied to the robot, and the force of the robot wearer in a state where the external force is compensated. When this is applied, a dynamic step of deactivating the position control of the robot to maintain a force that compensates for the external force, and performing a motion intended by the wearer by moving the robot according to the force applied by the robot wearer, and the static step And it is possible to support muscle strength by repeatedly performing the above dynamic steps.

Among the embodiments, a control device for a wearable robot receives a position vector value (q) and a position command value (q _d ) of the robot and calculates a position error (e), the position error (e). ) And performs PID (Proportion Integral Derivative) control to output the movement position control value (u) of the robot to remove the position error (e), and receives the position control value (u). An external force observing unit that integrates until the position control value (u) reaches the external force (Fe) and applies a gain (γ) to observe the external force, the position control value (u) output from the position control unit and the observed An external force compensating unit that receives an external force value and outputs an actuator force command value (τd) including a force that compensates the external force, and receives the position control value (u) and enters the "ON/OFF" state. And a switch unit that outputs the position control value (u) or "0" according to the input, and a position command unit that receives the output of the switch unit and double-integrates it and applies the integral gain (ρ) to output the position command value (q). do.

The disclosed technology can have the following effects. However, since it does not mean that a specific embodiment should include all of the following effects or only the following effects, it should not be understood that the scope of the rights of the disclosed technology is limited thereby.

The control method and apparatus for a wearable robot according to an embodiment of the present invention may assist various activities without using a separate sensor for determining the intention of the wearer.

In the control method and apparatus for a wearable robot according to an embodiment of the present invention, if the wearer applies only a force to perform an intended motion without the influence of an external force, the robot can complete the motion.

In the control method and apparatus for a wearable robot according to an embodiment of the present invention, the robot cannot move by activating the position control, but the external force applied can be compensated, and the external force is compensated by deactivating the position control. The output force of the actuator is maintained, and the robot can be moved by the force of the wearer.

Therefore, the control method and apparatus for a wearable robot according to an embodiment of the present invention can assist various activities with only a position sensor, thereby reducing the cost of configuring the wearable robot, and for all wearable robots capable of measuring position. It can have versatility that can be applied.

1 is a view for explaining a control system for a wearable robot according to an embodiment of the present invention.
2 is a view for explaining the wearable robot control device in FIG. 1.
3 is a diagram for explaining a state machine of a switch unit in FIG. 2.
4 is an exemplary diagram illustrating a simulation scenario of a robot motion to which a wearable robot control method according to an embodiment is applied.
5 is a graph showing user force and robot force for the simulation scenario of FIG. 4.

Since the description of the present invention is merely an embodiment for structural or functional description, the scope of the present invention should not be construed as being limited by the embodiments described in the text. That is, since the embodiments can be variously changed and have various forms, the scope of the present invention should be understood to include equivalents capable of realizing the technical idea. In addition, since the object or effect presented in the present invention does not mean that a specific embodiment should include all or only such effects, the scope of the present invention should not be understood as being limited thereto.

Meanwhile, the meaning of terms described in the present application should be understood as follows.

Terms such as "first" and "second" are used to distinguish one component from other components, and the scope of rights is not limited by these terms. For example, a first component may be referred to as a second component, and similarly, a second component may be referred to as a first component.

Singular expressions are to be understood as including plural expressions unless the context clearly indicates otherwise, and terms such as "comprises" or "have" refer to implemented features, numbers, steps, actions, components, parts, or It is to be understood that it is intended to designate that a combination exists and does not preclude the presence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

All terms used herein have the same meaning as commonly understood by one of ordinary skill in the field to which the present invention belongs, unless otherwise defined. Terms defined in commonly used dictionaries should be construed as having meanings in the context of related technologies, and cannot be construed as having an ideal or excessively formal meaning unless explicitly defined in the present application.

1 is a view for explaining a control system for a wearable robot according to an embodiment of the present invention.

Referring to FIG. 1, the control system 100 for a wearable robot includes a wearable robot control device 110, an actuator force control device 120, an external force conversion device 130, a robot action force summing device 140, and It includes a robot dynamics device 150.

The wearable robot control device 110 can calculate a force command value to be output by each actuator of the robot by receiving feedback input of each joint angle of the robot, and can transmit the calculated force command value to the actuator force control device 120. have. In one embodiment, the wearable robot control device 110 may receive a feedback from the robot dynamics device 130 with a position vector (q) of the robot that changes by forces applied by the robot according to the dynamics of the robot. . The wearable robot control device 110 may perform position control based on an error between the position command and the position of the robot. At this time, the wearable robot control device 110 can observe the external force and issue an actuator force command to the actuator force control device 120 including an external force compensation value capable of canceling the observed external force with respect to the position control value. have. In one embodiment, the wearable robot control device 110 may control whether or not the robot moves by "ON/OFF" position control through a switch function. The wearable robot control device 110 may operate by cycling through a static stage in which the robot cannot move and a dynamic stage in which the robot can move. The wearable robot control device 110 may perform an operation to compensate for an external force applied to the robot, although the robot cannot move in a static step. The wearable robot control device 110 maintains external force compensation in a dynamic stage so that if the robot wearer applies only a force to perform an intended motion without the influence of the external force, the robot moves and the wearer can complete the intended motion.

The actuator force control device 120 may control the force of each actuator of the robot. In one embodiment, the actuator force control device 120 may receive a force command (τ _d ) from the wearable robot control device 110 to operate a actuator provided in each joint of the wearable robot, and the output force of each actuator (τ _r ) can be transferred to the robot acting force summing device 140.

The external force conversion device 130 may convert the force at each joint by substituting the external force Fe into the Jacobian transposed matrix J ^T. The relationship between the joint force and the external force through the Jacobian transpose matrix in the Cartesian coordinate system is as shown in Equation 1 below.

[Equation 1]

τ = J ^T *Fe

The robot acting force summing device 140 may obtain a total of forces acting on the robot. In one embodiment, the robot acting force summing device 140 is a force acting on the robot by summing the output force of the robot driver (τ _r ) and an external force converted into a force at the robot joint and a force applied by the user to the robot (τ _h ). You can get the total sum of.

The robot dynamics device 150 may obtain a position vector (q) of the robot that changes by forces applied to the robot according to the dynamics of the robot. Here, the position vector (q) of the robot may mean the angle of each joint of the robot. The robot dynamics device 150 may receive the total sum of forces acting on the robot as an input, derive the position vector q of the robot through the dynamics equation, and feed back to the wearable robot control device 110. The dynamic equation of a typical exoskeleton robot system is shown in Equation 2 below.

[Equation 2]

Here, q ∈R ^nx1 is the joint position, D ( q ) ∈R ^nxn is the inertia matrix, and C ( q,q' ) ∈R ^nxn is the Coriolis force and the centrifugal matrix ( centrifugal term), and g ( q )∈R ^nx1 is the gravity term. τ _r , τ _h ∈R ^nx1 represent the general forces exerted by the robot and the user, respectively. J ( q )∈R ^6xn is the Jacobian matrix at point p ∈R ^3x1 , and F _e ∈R ^6x1 is the external force.

The total inertia of the system consists of the inertia of the robot, user (wearer), and external source when the object is fixed, so D ( q ), C ( q,q' ) and g(q) are the following equations: It can be defined as 3.

[Equation 3]

Here, the subscripts r, h, and e denote robots, users (wearers), and external factors, respectively.

2 is a view for explaining the wearable robot control device in FIG. 1.

2, the wearable robot control device 110 includes a position error calculation unit 210, a position control unit 220, an external force observation unit 230, an external force compensation unit 240, a switch unit 250, and a position. It includes a command unit 260.

The position error calculation unit 210 receives a position command value (q _d ) from the position command unit 260 and a feedback input of the position vector value (q) of the robot from the robot dynamics device 150 to calculate the position error (e). Can be calculated. In an embodiment, the position error calculation unit 210 may be implemented as an operator that calculates the position error e by subtracting the position vector value _{q from the position command value q d.}

The position control unit 220 may receive a position error e from the position error calculation unit 210 and output a position control value u for controlling the position of the robot. In an embodiment, the position control unit 220 may obtain a position control value u for controlling a movement position of the robot through a proportion integral derivative (PID) control method. Here, the position control value (u) obtained through the PID position control is a value obtained by converting the position error into force due to the gain, and this corresponds to an element for removing the position error of the robot. Even if this is not described in detail, it can be said to be obvious to those skilled in the art of PID position control.

The external force observing unit 230 may receive a position control value u from the position control unit 22 and observe the external force. In one embodiment, the external force observation unit 230 is the inverse of the Jacobian transposed matrix (J ^-T ), the integral (-γ/s), the Jacobian transposed matrix (J ^T ) with respect to the position control value (u). External force can be observed. The external force observation unit 230 may be implemented as a proportional integrator. In the case of a continuous external force (Fe), the output (u) of the position control unit 220 may be accumulated in the integrator of the external force observation unit 230 until the external force (Fe) is reached, and the gain (γ) is applied after integration. I can. The external force observed by the external force observation unit 230 may be transmitted to the external force compensation unit 240.

_{The external force compensating unit 240 may output a driver force command value τ d} for compensating the external force observed by the external force observing unit 230 with respect to the output u of the position control unit 220. The actuator force command value (τ _d ) may be defined by Equation 4 below.

[Equation 4]

는 자코비안 전치행렬을,

는 관측된 외력을, γ는 양의 상수를,

는 자코비안 전치행렬의 역행렬을 각각 나타낸다.

및 τ_h=g(q)가 되도록 구동기 힘 제어 장치(120)를 바르게 설계하고 사용자가 사용자와 로봇의 무게를 처리하면, 수학식 4는 아래 수학식 5와 같이 될 수 있다.Here, q is the position vector value representing the position of each joint of the robot that changes by the forces applied to the robot, which is determined by the dynamic equation of the robot, and U is the integration of the position control value (u) and the gain (γ). The value obtained by applying,

Is the Jacobian transposition matrix,

Is the observed external force, γ is the positive constant,

Represents the inverse matrix of the Jacobian transposed matrix, respectively.

And _{when the actuator force control device 120 is correctly designed so that τ h} = g(q) and the user processes the weight of the user and the robot, Equation 4 may be as Equation 5 below.

[Equation 5]

이고, K는 양의 상수이다.From here,

And K is a positive constant.

)이 갱신되게 된다. 이때, 위치 제어부(220)에 위치 지령(q_d)이 고정되면 로봇은 움직일 수 없다. 동적 단계는 이중 적분 루프가 형성되어 위치 제어가 중지되고 관측된 외력(

)이 고정되게 된다. 이때, 관측된 외력(

)이 유지되면서 이 상태에서 로봇은 움직일 수 있다. 스위치부(250)의 상태에 따른 구동기 힘 지령(τ_d)은 아래 수학식 6과 같다.The switch unit 250 may selectively transmit the position control output u of the position control unit 220 to the position command unit 260 to activate or deactivate the operation of the position control unit 220. In one embodiment, when the switch unit 250 is located between the output terminal of the position control unit 220 and the input terminal of the position command unit 260 and is in the "OFF" state, the position control output u is the position command unit. The feedback to the 260 is blocked, and the position control output u is transmitted to the position command unit 260 only when it is in the "ON" state. The switch unit 250 and the position command unit 260 may form a double integral loop when the switch unit 250 is in an “ON” state. Here, a static step may be performed when the switch unit 250 is "turn-off", and a dynamic step may be performed when it is "turn-on". In the static phase, the position command (q _d ) is not updated, the position control starts, and the observed external force (

) Will be updated. At this time, if the position command (q _d ) is fixed to the position control unit 220, the robot cannot move. In the dynamic phase, a double integral loop is formed, position control is stopped, and the observed external force (

) Will be fixed. At this time, the observed external force (

) Is maintained and the robot can move in this state. _{The driver force command (τ d} ) according to the state of the switch unit 250 is shown in Equation 6 below.

[Equation 6]

Here, u _deact represents the position control output deactivated by the double integral loop, which is close to zero.

Therefore, when the external force is to be compensated, the switch unit 250 is turned "off" and the external force is completely compensated and the switch unit 250 is turned "on" when the user wants to move. So that the control is carried out automatically.

)이 유지되는 동안 위치 제어부(220)를 비활성화하는 것에 의해 로봇이 사용자의 힘을 준수할 수 있다.The position command unit 260 may double-integrate the output of the switch unit 250 by applying a sufficiently large integral gain ρ, and feed back the output of the switch unit 250 to the position control unit 220 through the position error calculation unit 210. The position control unit 220 allows the robot to move as the position control output (u) converges to "0" by the position command unit 260, and the force to compensate for the external force observed by the external force observation unit 230 is Can be maintained. In one embodiment, the position command unit 260 forms a double integration loop and the observed external force (

) Is maintained, by deactivating the position control unit 220, the robot can comply with the user's force.

3 is a diagram for explaining a state machine of a switch unit in FIG. 2.

Referring to FIG. 3, in an initial state (Phase), the switch unit 250 is in a static stage in which the switch unit 250 is “OFF”, the posture of the robot is fixed, and an external force acting on the robot is observed. At this time, when the output force of the robot is in equilibrium with the applied external force, it transitions to the next state (Phase II). When the output force of the robot is in equilibrium with the external force applied, the position control output (u) of the position control unit 220 converges to "0", so the size of ∥u ∥ (norm of u) is δ for a _{certain period of time t 1 If it} is kept smaller than 1, it transitions to the next state (Phase II).

In the Phase II state, the switch unit 250 is a static stage in which the switch unit 250 is “OFF”, and the robot cannot move by fixing the posture, but the external force applied thereto may be compensated. After the external force is compensated for and the robot is in equilibrium with the external force, it transitions to the Phase III state when the user applies a force to move. At this time, when ∥u∥ is _{greater than δ 2} , it transitions to the next phase.

감소하기 시작하여 일정시간 t₃ 이내에 감소하기 시작한 시점의

값 보다 η_d 배 작아지면 다음 상으로 천이한다. 여기에서, 상태 천이 조건에 사용되는 변수들은 다음과 같이 정의될 수 있다.In the phase III state, the switch unit 250 is a dynamic step in which the switch unit 250 is "ON". In the previous state, the output force is maintained to compensate for the external force, and the robot can be moved by the user's force. When one operation is completed by the user's force, it transitions to the initial state, Phase I. _{The robot's end effector speed (v d} ) again converges to "0" as the robot completes the user's intended motion by the user's force, _{and the maximum reached after ∥v d} ∥ reaches the maximum value. If it is _{less than η m} times the value, it transitions to the next phase. Or the force acting on the robot suddenly changes, stopping the motion

When it starts to decrease and begins to decrease within _{a certain period of time t 3}

_{If η d} times smaller than the value, the transition to the next phase. Here, the variables used in the state transition condition can be defined as follows.

4 is an exemplary diagram illustrating a simulation scenario of a robot motion to which a wearable robot control method according to an exemplary embodiment is applied, and FIG. 5 is a graph showing a user force and a robot force according to the scenario of FIG. 4.

Referring to FIGS. 4 and 5, it is a scenario for an operation of lifting and moving a 5 kg object as a model of a robot to which a wearable robot control method according to an embodiment is applied. As shown in Figure 4, the object is lifted briefly and then moved to a higher place. As a result of performing the simulation according to this scenario, the force (τ _h ) and the actuator output force (τ _r ) exerted by the user to the robot are the same as the graphs shown in FIGS. 5A and 5B.

In the graphs of FIGS. 5A and 5B, the horizontal axis represents time (t), the vertical axes τ ₁ and τ ₂ represent the flexion/extension torque of the shoulder and elbow tee, respectively, and the phase represents the state transition as shown in FIG. 3. Initially, the weight of the user's arm and robot is compensated, and the object is lifted from 0.3 to 0.6 seconds. Since this object is supported only by the user, the weight of the object is not on the robot. The object is held from 0.6 to 1.5 seconds, the user's torque decreases, and the robot starts to offset the weight of the object. This means that the weight of the object is compensated by the robot and the object can be grasped without user effort during that period. If the user needs less torque, the object is moved to a higher position by 1.5 to 2 seconds. τ _h the size is greater than 2 seconds at about 1.8 * τ _h, This is because the force required in the same direction as the external force (the weight of an object). Since the weight of the object is compensated by the robot, the user must apply a force to the compensation force.

A control method and apparatus for a wearable robot according to an embodiment includes an external force compensating step of offsetting the external force by outputting a force having the same magnitude as the external force and in the opposite direction, and maintaining the force to cancel the external force, and according to the force applied by the user. By controlling to operate in a moving step, it is possible to assist the user's activities using only the joint position information of the robot. Therefore, it can be universally applied to a general upper limb exoskeleton robot platform.

Although described above with reference to the preferred embodiments of the present application, those skilled in the art will variously modify the present invention within the scope not departing from the spirit and scope of the present invention described in the following claims. And it will be appreciated that it can be changed.

100: wearable robot control system
110: wearable robot control device 120: actuator force control device
130: external force conversion device 140: robot acting force summing device
150: robot dynamics device
210: position error calculation unit 220: position control unit
230: external force observation unit 240: external force compensation unit
250: switch unit 260: position command unit

Claims (10)

The position error (e) is calculated by calculating the position error (e) by receiving the position vector value (q) and the position command value (q _{d) of the robot, and performing PID (Proportion Integral Derivative) control based on the position error (e).} A position control step of outputting a position control value (u) for controlling a movement position of the robot for removing the skeletal robot;
An external force observing step of receiving the position control value u, integrating until the position control value u reaches an external force Fe, and observing an external force by applying a gain γ;
An external force compensating step of subtracting the observed external force value from the position control value (u _{) and outputting a driver force command value (τ d} ) including a force for compensating the external force;
A double integration step of receiving the position control value (u), double-integrating it through an integral gain (ρ), _{and feeding back the position command value (q d );} And
A control method for a wearable robot comprising a switch step of selectively providing the position control value (u) output in the position control step to the double integration step according to a state transition condition.
delete delete delete The method of claim 1, wherein the double integration step
When the switch step is in the "ON" state, the position control is deactivated by _{performing double integration on the position control value (u) and providing the position command value (q d) to the position control step.} Control method for wearable robots.
The method of claim 1, wherein the switching step
It is automatically controlled to be in a "turn-off" state to compensate for the external force acting on the robot, and to be in a "turn-on" state for the operation of the robot by the force exerted by the user to the robot after the external force is compensated. Control method for a wearable robot, characterized in that.
The method of claim 6, wherein the switching step
A wearable robot, characterized in that when an external force is compensated in an "OFF" state and the output force of the actuator of the robot is in equilibrium with the external force, it transitions to an "ON" state when a user applies a force to move it. Method for control.
The method of claim 7, wherein the switching step
In the "ON" state, when the motion by the user's force is completed and the speed of the end of the robot converges to "0", or the motion is stopped due to a sudden change in the force acting on the robot, it is "OFF". Control method for a wearable robot, characterized in that the transition to the state.
A static step of activating the position control of the robot to fix the posture of the robot and to compensate for an external force applied to the robot; And
When the force of the robot wearer is applied while the external force is compensated, the position control of the robot is deactivated to maintain the force to compensate for the external force, and the robot is moved according to the force applied by the robot wearer to perform the motion intended by the wearer. Contains dynamic steps to perform,
Control method for a wearable robot that assists muscle strength by repeatedly performing the static step and the dynamic step.
A position error calculator configured to receive a position vector value (q) and a position command value (q _d ) of the robot and calculate a position error (e);
A position control unit configured to receive the position error (e) and perform a PID (Proportion Integral Derivative) control to output a movement position control value (u) of the robot to remove the position error (e);
An external force observing unit receiving the position control value u, integrating until the position control value u reaches an external force Fe, and observing an external force by applying a gain γ;
An external force compensating unit for receiving a position control value u output from the position control unit and the observed external force value and outputting a driver force command value τd including a force compensating for the external force;
A switch unit receiving the position control value u and outputting the position control value u or 0 according to an "ON/OFF"state; And
Control device for a wearable robot comprising a position command unit that receives the output of the switch unit, double-integrates, and outputs a position command value (q) by applying an integral gain (ρ).

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