FORCE-POSITION CONTROLLER DESIGN FOR 4 DOF… 39th volume/7 REHABILITATION ROBOT ARM.pdf · robotic...

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International Journal of Information Technology and Business Management 29 th July 2015. Vol.39 No.1 © 2012-2015 JITBM & ARF. All rights reserved ISSN 2304-0777 www.jitbm.com 84 FORCE-POSITION CONTROLLER DESIGN FOR 4 DOF'S REHABILITATION ROBOT ARM USING PSO ALGORITHM Asst. Prof. Dr. MOHAMMED Y. HASSAN Mr. ZEYAD A. KARAM [email protected] [email protected] Control and Systems Engineering Department University of Technology Baghdad, Iraq ABSTRACT: Human limbs disability such as full or partial loss of function of the upper limb is a common impairment in the elderly and due to strokes, sports injuries, and occupational injuries. The conventional rehabilitation approach is to assist patient to perform Activities of Daily Living (ADL) through a set of pre- programmed trajectories. Therapist performs the rehabilitation program to the patient. This work focuses on designing, simulating and implementing a 4 DoF's (3 active joints), non- wearable rehabilitation robot for arm movements. The nonlinear mathematical model of the robot includes kinematic and dynamic models for the 4 DoF's (3 active joints), is developed and simulated using MATLAB. The friction term of robot actuators with the external disturbances of the patient limb on the robot links are considered. Intelligent Force-Position controllers incorporated PD-like Fuzzy Logic position control are designed to track the required medical trajectories for the simulated and implemented robot. Particle Swarm Optimization (PSO) algorithm is used to tune the gains of the position part of the Force- Position controller's to reach minimum position error, minimum oscillation and minimum overshoot in the position of each joint. These controllers are implemented using MATLAB Simulink. The controllers are controlling the implemented rehabilitation robot using two Data Acquisition Cards (Advantech PCI-1712), which generate and reads the required digital and analog signals for the robot. Index Terms: Force-Position control, Rehabilitation robot, Intelligent controller, Robot dynamics, Medical trajectories, PSO algorithm, Advantech card. I. INTRODUCTION Robotics sciences are playing as important domain in several applications; like industrial and medical applications. Robotics are using in rehabilitation programs and many other medical processes. Therapist performs the rehabilitation program but the drawback in the method of treatment may occur in incorrect therapeutic movements which result from fatigue therapist during the treatment section. This is leading to a negative impact on the patient person. Here comes the role of the robot. Which leads movements consistent and repeated tirelessly or fatigue that can be used in hospital or at home for assisting in ADL and many patients can work with it at day [1]. The drawback was in the wearable position and alignment for the human hand. Ueda et al. in 2011 [4], proposed a new method, named (individual muscle-force control), for a wearable robot. The main drawback was the workspace limitations with not considering the friction term in pneumatic actuators. Stiffness and impedance control concepts proposed by Mehdi and Boubaker in 2012 to solve position and force control for robot-aided rehabilitation. The main drawback in this work is not accurate tracking for the desired medical trajectory [5]. In this work, the intelligent controller for 4 DoF's (3 active joints), non-wearable rehabilitation robot is designed to control the simulated and implemented robot. The nonlinear mathematical

Transcript of FORCE-POSITION CONTROLLER DESIGN FOR 4 DOF… 39th volume/7 REHABILITATION ROBOT ARM.pdf · robotic...

International Journal of Information Technology and Business Management 29

th July 2015. Vol.39 No.1

© 2012-2015 JITBM & ARF. All rights reserved

ISSN 2304-0777 www.jitbm.com

84

FORCE-POSITION CONTROLLER DESIGN FOR 4 DOF'S REHABILITATION

ROBOT ARM USING PSO ALGORITHM

Asst. Prof. Dr. MOHAMMED Y. HASSAN Mr. ZEYAD A. KARAM

[email protected] [email protected]

Control and Systems Engineering Department

University of Technology

Baghdad, Iraq

ABSTRACT:

Human limbs disability such as full or partial loss of function of the upper limb is a common

impairment in the elderly and due to strokes, sports injuries, and occupational injuries. The conventional

rehabilitation approach is to assist patient to perform Activities of Daily Living (ADL) through a set of pre-

programmed trajectories. Therapist performs the rehabilitation program to the patient.

This work focuses on designing, simulating and implementing a 4 DoF's (3 active joints), non-

wearable rehabilitation robot for arm movements. The nonlinear mathematical model of the robot includes

kinematic and dynamic models for the 4 DoF's (3 active joints), is developed and simulated using

MATLAB. The friction term of robot actuators with the external disturbances of the patient limb on the

robot links are considered. Intelligent Force-Position controllers incorporated PD-like Fuzzy Logic position

control are designed to track the required medical trajectories for the simulated and implemented robot.

Particle Swarm Optimization (PSO) algorithm is used to tune the gains of the position part of the Force-

Position controller's to reach minimum position error, minimum oscillation and minimum overshoot in the

position of each joint.

These controllers are implemented using MATLAB Simulink. The controllers are controlling the

implemented rehabilitation robot using two Data Acquisition Cards (Advantech PCI-1712), which generate

and reads the required digital and analog signals for the robot.

Index Terms: Force-Position control, Rehabilitation robot, Intelligent controller, Robot dynamics, Medical

trajectories, PSO algorithm, Advantech card.

I. INTRODUCTION

Robotics sciences are playing as important

domain in several applications; like industrial and

medical applications. Robotics are using in

rehabilitation programs and many other medical

processes. Therapist performs the rehabilitation

program but the drawback in the method of

treatment may occur in incorrect therapeutic

movements which result from fatigue therapist

during the treatment section. This is leading to a

negative impact on the patient person. Here comes

the role of the robot. Which leads movements

consistent and repeated tirelessly or fatigue that can

be used in hospital or at home for assisting in ADL

and many patients can work with it at day [1]. The

drawback was in the wearable position and

alignment for the human hand. Ueda et al. in 2011

[4], proposed a new method, named (individual

muscle-force control), for a wearable robot. The

main drawback was the workspace limitations with

not considering the friction term in pneumatic

actuators. Stiffness and impedance control concepts

proposed by Mehdi and Boubaker in 2012 to solve

position and force control for robot-aided

rehabilitation. The main drawback in this work is not

accurate tracking for the desired medical trajectory

[5].

In this work, the intelligent controller for 4

DoF's (3 active joints), non-wearable rehabilitation

robot is designed to control the simulated and

implemented robot. The nonlinear mathematical

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th July 2015. Vol.39 No.1

© 2012-2015 JITBM & ARF. All rights reserved

ISSN 2304-0777 www.jitbm.com

85

main reason of developing robotic treatments is the

current emphasis on cost reduction in health care

through shorter patient rehabilitation length [2].

Xianzhi et al. in 2010 [3], designed a hybrid

force position controller using fuzzy logic for the

robotic arm of 9 DoF's for the upper limb of

wearable exoskeleton rehabilitation robot. The

model for the proposed rehabilitation robot is

derived and simulated by Matlab. Also, the effect of

the friction in the joints and the external disturbances

that affect in the rehabilitation robots when touched

to the patient body are considered in the robot

model. The controller is a Force-Position controller

incorporates PD-like Fuzzy logic position

controllers to deal with the force and position that

affect on the robot links by the patient limb.

A Particle Swarm Optimization Algorithm

(PSO) is used to tune the Position part of Force-

Position controller's gains to get the desired medical

trajectories with minimum position error, minimum

overshoot and minimum oscillation in the simulated

robot tests.

II. DESIGNING AND MODELING OF 4 DOF'S

REHABILITATION ROBOT The overall structure of proposed 4 DoF's

rehabilitation robot for human upper limb motion

design is shown in Figure 1. This structure is

manufactures with respect to medical designs of

rehabilitation robots. The mechanical design of the

robot and structure was presented in [6]. .

Kinematical model:

In this research, the proposed rehabilitation

robot is modeled based on the concepts of, human

upper limb articulations and movements to

rehabilitate and to ease shoulder and elbow joint

motions to assist human daily activity properly. The

rehabilitation device has three degrees of freedom,

which are:

Shoulder abduction/adduction (one DOF).

Shoulder flexion/extension (one DOF).

Elbow flexion-extension (one DOF).

The DH parameters according to co-ordinate

frames that presented in [9], are listed in Table (1). The homogenous transformation matrix that

relates frame (4) to frame (0) can be obtained by

multiplying individual transformation matrices [7]:

= (1)

Dynamic model: Using the Euler–Lagrangian formulation, the

dynamics of robot manipulators with rigid links can

be written as [7]:

depends on many factors such as lubrication,

temperature, interaction surface, displacement and

relative velocity of robot. It is highly nonlinear

effect and result in steady state errors, limit cycles,

and poor performance [8]. The friction model with

its simulation was present in [9]. In this work, the

singularity occurs at configuration of end effector

with the base of robot. This configuration is similar

to the articulated configuration 3 DoF's. The singular

configuration with its solution was present in

[6].Figure 2 shows the block diagram of dynamic

model and Figure 3 shows the simulink model of 4

DoF's (3 active joints), rehabilitation robot. The

parameters of the dynamic model were presented in

[9].

III. Design and Simulation of Force-Position

Controlled Rehabilitation Robot Force-Position controller is a control strategy

specifying a desired dynamic behavior for the robot.

The most common feature in many robotic

applications is the motion of the robot manipulator

within an unconstrained space like the end effector

and the links of the manipulator are not in contact

with the environment. Force-Position control was an

approach considers the relationship between the

position of the manipulator and the contact forces

imposed by the environment. This relationship can

be modeled by generalized

Force-Position characterized by inertial,

damping and stiffness properties, associated to the

manipulator [10]. The contact between the

manipulator and its environment results in increasing

the complexity of the industrial processes that need

for robotic technology demands. Taking this

problem in consideration, results in a new control

problem. The objective of the Force-Position control

strategy is the successful execution of an interaction

task with the environment. Such an interaction

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( ) ̈ ( ̇) ̇ ( ̇) ( ) (2)

Where q ∈ denotes the vector of generalized

displacements, τ ∈ denotes the vector of

generalized control input torques, D(q) ∈ is the

inertia matrix, ( ̇) ∈ is the Coriolis matrix,

F( ̇) ∈ are the Friction terms, G (q) ∈ is the

gravity vector, and ∈ represents disturbances

which are bounded [7]. Friction model and singularity solution: Friction is an undesirable phenomenon in the

performance of controlled electromechanical motion

systems. The effect of friction on robotic system

requires the control of both, motion and interaction

forces [11].

The robot controller is designed to track the

motion trajectory and realize the desired force

dynamics between the end-effecter position and the

contact force the desired force is defined as [12]:

F ( ) ( ̇ ̇) ( ̈ ̈) (3)

Where F ∈ is the vector of contact generalized

forces exerted by the manipulator on the

environment; P is the task space dimension. ,

and ∈ are the desired stiffness, damping

and inertia matrices respectively, X, ̇ and ̈ ∈ are

the position, velocity and acceleration

respectively of the robot system in the Cartesian

space. The control law of the force that is applied to

the dynamic model of robot is [13]:

U = ( ) [ ( ) + ( ̇ ̇ ) + ( +I)

− F] +G

(4)

Figure 4 represents the block diagram of closed loop

Force-Position controlled system for 4 DoF's

rehabilitation robot, where U ∈ is the control law

applied to robot model, J(q) ∈ is the Jacobean

matrix and , and ∈ are the position,

velocity and force gain matrices, respectively. All

design of the controller with it parameters was

present in [9].

The Position part controller of each joint that

incorporating in the Force-Position control is; a PD

like Fuzzy Logic type (FLC) to deal efficiently with

the nonlinearities in robot mode and tracking the

desired medical position trajectories with minimum

overshoot and minimum oscillation. All Fuzzy

controller parameters and membership functions

with rules table was present in [9]. The parameters

of the Force controller incorporating in the Force-

Position control, of equation 10 are selected as;

Kd=60 (N/m), Bd=150 (N·s/m) and Md=2 (kg).

These values are representing second order model

with damping ratio and un-damped natural

frequency of ζ=0.785 and wn=0.523 (rad/sec)

respectively [10]. The objective of this control

concept is to accomplish specific mechanical

This trajectory is transformed into Cartesian

coordinates using the direct kinematics in order to

obtain the desired trajectory = where:

( ) (6)

(t) = cos ( ) cos ( + ) (7)

( ) Sin ( ) sin ( ) (8)

Where ( ) [i=3, 4] is the generated angle

for the desired trajectory. Assuming the desired force

of = (N) is applied to the first position

trajectory in the (Y, Z) axes motion and assume the

position in the X axis is fixed at 0.148 (m). The gains

of the PD-like position FLC for first position

trajectory parameters are selected using trial and error

as illustrated in Table (2):

The closed loop Force-Position controlled of

position responses for the first trajectory of the end

effecter without disturbance is shown in Figure 6. The

position response with the affect of (0.05sin (0.5ωt))

as disturbances N.m are shown in Figure 7. The

second reference position trajectory of half ellipse is

applied to move the three joints together at the same

time. The parameters of controller are selected by trial

and error for the second half ellipse trajectory and

illustrated in Table (3):

Figure 8 show the position responses of the

second trajectory on end effector without

disturbances. The position response of the second

trajectory with (0.08 sin ( )) as disturbance on the

forth joint is shown in Figure 9.

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87

impedance at the manipulator end-effector. The

manipulator controller is designed to track a motion

trajectory and realize a desired dynamic relationship

between the end effector position and the contact

force [11]. The Simulink that represents the closed

loop Force- Position controller of the rehabilitation

robot was shown in Figure 5.

IV. MEDICAL TRAJECTORIES WITH

SIMULATION RESPONSES Two reference position trajectories were applied;

the first position trajectories are generated by using

a cubic interpolation and its two axes trajectory. The

initial and final end effecter joint angles of the robot

are ( ( ) ( ) ), ( ( ) ( ) ) and ( ( ) ( ) ) for shoulder abduction respectively, where ( ) is

the initial time and ( ) is the final time of motion.

The trajectory is the time of planning in such a way

that the robot arrives at the final configuration in = 60 (s). The planned trajectory is [11]:

( ) ( ) [ ( ) ( )

] [

( ) ( )

]

(5)

V. PSO AS AN OFF-LINE POSITION

CONTROLLER GAINS TUNING ALGORITHM

In PSO algorithm, each member of the

population is called a ‘‘particle’’, and each particle

‘‘flies’’ around in the multidimensional search space

with a velocity, which is constantly updated by the

particle’s own experience and the experience of the

particle’s neighbors or the experience of the whole

swarm. It has already been applied in many areas,

such as function optimization, artificial neural

network training, pattern classification and fuzzy

system control [13].

The particle swarm optimization (PSO)

algorithm is performed as follows:

1) The unknown parameters are called the

particles that form the population size denoted by

n.

2) Starting with a randomly initialization, the

particles will move in a searching space to

minimize an objective function.

3) The parameters are estimated through

minimizing the objective function.

4) The fitness of each particle is evaluated

according to the objective function for updating

the xpbest (previous best position) of particle and

the xgbest (global best position) among all

particles as two goals in each step of computing.

5) Each particle is directed to its previous

xpbest position and the previous xgbest position

among particles.

Consequently, the particles tend to fly towards the

better searching areas over the searching space. The

velocity of i-th particle will be calculated as [13]:

( ) ( ( ) ( ( ) ( ))+ (gbest − (k))) (9)

Where for the i-th particle in the k-th iteration, ( ) is the position, ( ) is the previous best

position, (gbest) is the previous global best position

of particles, ( ) and ( ) are the acceleration

coefficients namely the cognitive and social scaling

parameters, ( ) and ( ) are two random numbers

in the range of [0 1] and (χ) is constriction

coefficient given by [13]:

√ (10)

VI. PSO-BASED FORCE-POSITION CONTROL

SIMULATION RESPONSES

The fitness function is selected as (for all cases

of using PSO):

F=RMSE*0.95+ (overshoot*0.05) (13)

For the first medical trajectory without

disturbances More than ten tests have been done to

tune the gains of the controller using PSO. Table (4)

illustrates the best three values of gains according to

correction criteria (Percentage of enhancement) and

Table (5) illustrates the gains for each case that

obtained by PSO.

Table (4) illustrates that the second trial gives

the higher percentage of correction (minimum

fitness). Figure 11 shows the first position trajectory

response obtained using PSO-based controller.

For the first medical trajectory with previous

disturbance more than ten tests have been done to tune

the gains of the controller using PSO with

disturbance. Table (6) illustrates the best three values

of gains according to correction criteria (Percentage of

enhancement), and Table (7) illustrates the gains for

each case that obtained by PSO.

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Where (ϕ = , ϕ > 4), Constriction

coefficient is controlled by the convergence of the

particle. As a result, it prevents explosion and

ensuring convergence. A new position of the i-th

particle is then calculated as:

( ) ( ) ( ) (11)

The particle swarm is used as an

optimization algorithm (off-line) to find the best

gains of Fuzzy PD-like position controller to obtain

accurate position responses by minimizing the error

in the position trajectories and minimizing the

overshoot in position responses. This minimization

gives closer matching between the desired and the

actual trajectories. The PSO runs off-line, thus

computing time is not as important as in real time

control. All elements of PSO are changed for many

tests until reach the largest enhancement at

minimum fitness function. Figure 10 shows the

block diagram for PSO-based controller.

The fitness function that used to evaluate the

fitness of each particle the Root Mean Squared

Error (RMSE) and the overshoot in position

responses are included in the fitness function. The

RMSE that included is [13]:

( )

∑ √

( ) ( )

( ) (12)

Where (i) is the trajectory error of the i-th

sample for the first joint, (i) is the trajectory error

of the i-th sample for the third joint and (i) is the

trajectory error of the i-th sample for the fourth

joint, N is the number of samples, and k is the

iteration number.

Table (6) illustrates that the third trial gives the

higher percentage of correction (minimum fitness).

Figure 12 shows the first position trajectory response

obtained using PSO-based controller.

For the second half ellipse medical trajectory

More than ten tests had done to tune the gains of the

controller using PSO. Table (8) illustrates the best

four values of gains according to correction criteria

(Percentage of enhancement) and Table (9) illustrates

the gains for each case that obtained by PSO.

Table (8) illustrates that the first trial gives the

higher percentage of correction (minimum fitness).

Figure 13 second (half ellipse) position trajectory

response obtained using PSO-based controller.

For the second half ellipse medical position

trajectory with previous disturbance more than ten

tests had done to tune the gains of the controller using

PSO with disturbance. Table (10) illustrates the best

three values of gains according to correction criteria

(Percentage of enhancement), and Table (11)

illustrates the gains for each case that obtained by

PSO.

Table (10) illustrates that the first trial gives

the higher percentage of correction. Figure 14 shows

the second (half ellipse) position trajectory response

obtained using PSO-based controller.

VII. THE IMPLEMENTED ROBOT TEST

All implementation for the mechanical

structure and the interfacing system for controlling

the physical robot actuators can be shown in [7],

Figure 15 shows the input/output blocks of

Advantech chard by MATLAB for interfacing the

Force-Position controller with hardware parts via

two card. The previous quadratic medical trajectory

used in the physical robot tests, two tests are applied

angle only in . Table (12) illustrates the controller

parameters of manual tuning by trial and error.

Figure 16 shows the position trajectory

responses of the first test. he second test of the

position medical trajectory includes applying a 0 to

the third joint angle and 5 to the fourth joint angle

and the first angle assumed in the rest position with

controller does not compensate the effect of friction

and other nonlinearities that exist in the model.

PSO algorithm is used to tune the gains of

position part of the Force- Position control for

minimized the position error, minimized oscillation

and minimized overshoot of medical trajectories in the

simulated robot model. The enhancements in the

position trajectories are illustrated in Table (16),

compared with the conventional one, which were

measured using RMSE criteria.

The results give an indication about the enhancement

in the position trajectories responses of minimized

overshoot and error in position.

In the implemented robot medical trajectory

tests the RMSE is calculated for each test to obtain the

enhancement between conventional Force-Position

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0 . The Force–Position conventional controller gains

for second test are illustrated in Table (13) and

chosen by trial and error. Figure 17 shows the

position trajectory response of the second test.

The PSO algorithm is used in the

implemented robot tests to tune the parameters

gains of the controllers to generate trajectory

responses with minimum overshoot, minimum rise

time and minimum errors in position trajectory. The

best gains used for the first test are illustrated in

Table (14).

Figure 18 shows the position trajectory

response of the first test using PSO. Also, the PSO

algorithm is used in the second test of the position

medical trajectory to tune the parameters gains of

the controller. Table (15) illustrates the gains of

Force-Position controller obtained by PSO. Figure

19 shows the position trajectory response of the

second test with PSO.

VIII. CONCLUSIONS

It can be concluded from this work that:

Force-Position controllers incorporate a PD-

like fuzzy logic position controllers were used to

control the simulated and implemented robot. These

controllers deal with injured limb force and

minimize the oscillation and the overshoot in the

medical trajectories. For the Force-Position

conventional controller test, the maximum errors

exist in each axis without applying disturbance is:

40 (mm) in X axis and 3 (mm) in Y axes. By

applying disturbances, the maximum error found to

be 20 (mm) in X axis and 10 (mm) in Y axes.

Comparing these results with the Force-Position

controller used in reference [12], it is found that the

position of the end effecter in the mentioned

reference is fluctuated around the desired trajectory

because this type of

controllers and PSO-based controllers. Table (17)

illustrates the RMSE enhancement for the two tests of

position medical trajectory.

Finally, the proposed robot can be used at

homes and hospitals for the stroke injured persons to

get their daily life activates instead of therapists with

correct medical trajectories. The development of the

rehabilitation robots is the current emphasis on cost

reduction of the health care through shorter length for

the patient rehabilitates achieved by using robots.

IX. List of Tables Table (1) DH parameters.

1 0 0 2 0 3 0 0 4 0 0

Table (2) Gains of the PD-like FLC.

Gain

KP1 KV1 KO1 KP2 KV2 KO2 KP3 KV3 KO3

1 0.1 25 4 0.1 22 3 0.01 7

Table (3) PD-like position FLC gains for the second (half ellipse) trajectory.

Gain KP1 KV1 KO1 KP2 KV2 KO2 KP3 KV3 KO3

3 1 25 8 1 22 3 1 10

Table (4) Tests for the first position trajectory without disturbance.

Trial

Fitness by

conventional

controller

Global

Fitness

using

PSO

C1 C2

Number

of

Iterations

Number

of birds

Percentage of

enhancement

1 0.0090 0.0065 3 2 50 25 27.777%

2 0.0090 0.0054 3 3 50 30 40%

3 0.0090 0.0065 2.5 2.5 30 30 27.777%

Table (5) Gains of the controller that obtained by PSO for the first position

trajectory without disturbance.

Gains KP1 KV1 KO1 KP2 KV2 KO2 KP3 KV3 KO3

First

trial

0.0100 0.0100 0.0100 6.5878 0.5784 3.6587 5.3378 2.3390 8.4337

Second

trial

1.2725 1.2933 2.3211 7.8968 1.0418 3.6029 6.5446 0.5129 10.9934

Third

trial

0.5722 1.7910 1.7684 3.9034 2.0303 2.2109 6.0479 3.0921 9.5513

Table (6) Experiments for the first trajectory position with disturbance.

Trial

Fitness by

conventional

controller

Global

Fitness

using

PSO

C1 C2

Number

of

Iterations

Number

of birds

Percentage of

enhancement

1 0.0067 0.0062 3.5 3.5 30 40 7.462%

2 0.0067 0.0052 3.2 3.2 30 35 22.388%

3 0.0067 0.0046 3 3 25 50 31.343%

Table (7) Gains of the controller that obtained by PSO for first position

trajectory with disturbance.

Gains KP1 KV1 KO1 KP2 KV2 KO2 KP3 KV3 KO3

First

trial

0.9571 1.7661 0.7244 7.1753 10.9180 3.7042 4.1858 1.9533 5.9531

Second 2.6968 1.5353 0.0100 17.0000 5.1432 3.4535 12.1037 2.7169 3.2169

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trial

Third

trial

1.5991 0.3014 1.9889 14.7002 0.8848 15.0000 14.6674 3.4504 7.9361

Table (8) Experiments for the second (half ellipse) position trajectory without disturbance.

Trial

Fitness by

conventional

controller

Global

Fitness

using

PSO

C1 C2

Number

of

Iterations

Number

of birds

Percentage of

enhancement

1 0.0239 0.0175 3 3.3 30 40 26.778%

2 0.0239 0.0202 3.3 3.2 25 50 15.481%

3 0.0239 0.0182 3.2 3.2 50 50 23.849%

Table (9) Gains of controller obtained by PSO for the second (half ellipse)

position trajectory without disturbance.

Gains KP1 KV1 KO1 KP2 KV2 KO2 KP3 KV3 KO3

First

trial

25.000

0

0.0100 21.192

4

9.3754 1.5471 9.6093 6.5641 1.4807 5.2595

Second

trial

13.000

0

0.3931 13.000

0

12.441

8

7.0142 4.3010 4.5512 1.7591 6.5945

Third

trial

20.000

0

0.2105 19.430

8

17.740

6

2.3100 8.5033 4.0471 0.7969 8.5372

Table (10) Experiments for the second (half ellipse) position trajectory with disturbance.

Trial

Fitness by

conventional

controller

Global

Fitness

using

PSO

C1 C2

Number

of

Iterations

Number

of birds

Percentage of

enhancement

1 0.0211 0.0186 3 3 40 60 11.848%

2 0.0211 0.0195 3.1 3 40 40 7.582%

3 0.0211 0.0194 3.3 3.3 40 50 8.056%

Table (11) Gains of controller obtained by PSO for the second (half ellipse)

position trajectory with disturbance.

Gains KP1 KV1 KO1 KP2 KV2 KO2 KP3 KV3 KO3

First

trial

20.000

0

0.8931 20.000

0

6.4198 4.8270 18.968

2

9.7195 1.4940 4.5060

Second

trial

11.527

7

0.0100 17.000

0

16.328 2.1783 6.7021 5.4213 0.3165 6.6004

Third

trial

17.000

0

2.9058 12.636

8

11.699

7

2.7631 11.904 9.1536 0.6940 3.9384

Table (12) Force-Position conventional controller's gains.

Gain KP1 KV1 KO1 KP2 KV2 KO2 KP3 KV3 KO3

1 0.1 3 5 0.1 3 20 2 0.1

Table (13) Force-Position conventional controller's gains.

Gain KP1 KV1 KO1 KP2 KV2 KO2 KP3 KV3 KO3

1 0.1 3 7 0.1 7 25 0.1 2 Table (14) Force-Position controllers gains using PSO.

Gain KP1 KV1 KO1 KP2 KV2 KO2 KP3 KV3 KO3

1.2725 1.2933 2.3211 7.8968 1.0418 2.3029 6.5446 0.5129 1.7934

Table (15) Force-Position controller gains using PSO.

Gain KP1 KV1 KO1 KP2 KV2 KO2 KP3 KV3 KO3

14.1792 2.5854 12.9555 16.000 1.4252 3.5043 15.000 2.0752 5.0000

Table (16) Enhancement by using PSO.

Fitness by conventional

controller

Global Fitness using

PSO

Percentage of

enhancement

First Position trajectory without disturbance

0.0090 0.0054 40%

First Position trajectory with disturbance of (0.05 sin (0.5wt))

0.0062 0.0046 31.343%

Second (half ellipse) Position trajectory without disturbance

0.0239 0.0175 26.778%).

Second (half ellipse) Position trajectory with disturbance of

(0.08 sin (wt))

0.0211 0.0186 11.848%

Table (17) Percentage of enhancement.

First test

RMSE without

PSO

RMSE with

PSO

Percentage of

enhancement

0.0877 0.0644 26.5678%

Second test

RMSE without

PSO

RMSE with

PSO

Percentage of

enhancement

0.0261 0.0219 16.0919%

I. List of Figures

Figure 1.The proposed rehabilitation robot structure with 4 DOF's

(3 active joints) for upper limb movements

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91

Figure 2. Block digram of rehabilitation robot daynamic model.

Robot

Dynamic

Model

Forward

Kinematics

+

_

X=F()

Xd

3 PD Fuzzy

Logic

Controllers

for each axis

(Position

Controllers)

KP

Kvd/dt

+

+

+

+

+

ux

uy

uz

JT

+

+

G

U

Kd

Bd

Mdd/dt

+

_

Fd

-

-

-

+

F

Kf

Figure 4. Closed loop Force-Position controlled system.

Figure 3. Dynamic model of 4 DoF's (3 active joints), rehabilitation robot using simulink.

dq1 q1ddq1

dq3 q3ddq3

dq4 q4ddq4

dis4

dis_4

dis3

dis_3

dis1

dis_1

d2

d2

a4

a4

a3

a3

a1

a1

t4

T4

t3

T3

t1

T1

dq1

dq3

dq4

F1

F3

F4

Subsystem

Scope2

Scope1

ScopeSaturation3

Saturation2

Saturation1

R2D

Radians

to Degrees2

R2D

Radians

to Degrees1

R2D

Radians

to Degrees

signal1

signal2

signal3

signal4

signal5

signal6

signal7

signal8

signal9

signal10

signal11

signal12

signal13

signal14

signal15

signal16

signal17

signal18

signal19

Mux

1/s

Integrator5

1/s

Integrator4

1/s

Integrator3

1/s

Integrator2

1/s

Integrator1

1/s

Integrator

MATLAB

Function

Dynamic model

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92

Figure 6. The first position trajectory response.

Figure 7. The first position trajectory response with disturbance.

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8-0.7

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

0.1

z axis (meter)

y a

xis

(m

ete

r)

first trajectory

desired

actual

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8-0.7

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

z axis (meter)

y a

xis

(m

ete

r)

first trajectory response with disturbance

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93

Figure 5. The complete Force-Position controlled system of the proposed rehabilitation robot.

FX FY FZ

0.35 zd

100 tf0 t

a1 d2 a3 a4 dis1

dis3

dis4

T1 T3 T4

q1 q3 q4

robo

t_m

odel

-K- kfz

-K- kfy

-K- kfx

1 fzd0 fyd0 fxd

MA

TLA

B

Func

tion

forw

ord_

kina

mtic

s

0 dis40 dis30 dis1

0.1

d2

MA

TLA

B

Func

tion

cont

rolle

r_eq

uatio

ns

0.31

1

a4

0.34

1

a3

0.14

8

a1

yd

To W

orks

pace

7

xd

To W

orks

pace

6

yf

To W

orks

pace

3

xf

To W

orks

pace

1

t

To

Wor

kspa

ce

Sco

pe9

Sco

pe8

Sco

pe7

Sco

pe6

Sco

pe5

Sco

pe4

Sco

pe31

Sco

pe30

Sco

pe3

Sco

pe29

Sco

pe28

Sco

pe27

Sco

pe26

Sco

pe25

Sco

pe24

Sco

pe23

Sco

pe22

Sco

pe21

Sco

pe20

Sco

pe2

Sco

pe19

Sco

pe18

Sco

pe17

Sco

pe16

Sco

pe15

Sco

pe14

Sco

pe13

Sco

pe12

Sco

pe11

Sco

pe10

Sco

pe1

Sco

pe

R2D

Rad

ians

to D

egre

es2

R2D

Rad

ians

to D

egre

es1

R2D

Rad

ians

to D

egre

es

sign

al1

sign

al2

sign

al3

sign

al4

sign

al5

sign

al6

sign

al7

sign

al1

sign

al2

sign

al3

sign

al4

sign

al5

sign

al6

sign

al7

sign

al8

sign

al9

sign

al10

sign

al11

sign

al12

sign

al13

sign

al14

sign

al15

2 Mdz

2 Mdy

2 Mdx

MA

TLA

B

Func

tion

MAT

LAB

Fcn

1

60 KD

Z

60 KD

Y

60 KD

X

1

Gai

n9

7 Gai

n8

22 Gai

n7

25 Gai

n6

-K-

Gai

n5

3

Gai

n4

-K-

Gai

n3

4

Gai

n2

-1 Gai

n12

-1 Gai

n11

-1 Gai

n10

-K-

Gai

n1

-1 Gai

n

Fuzz

y Lo

gic

Con

trolle

r2

Fuzz

y Lo

gic

Con

trolle

r1

Fuzz

y Lo

gic

Con

trolle

r

du/d

t

Der

ivat

ive8

du/d

t

Der

ivat

ive7

du/d

t

Der

ivat

ive6

du/d

t

Der

ivat

ive5

du/d

t

Der

ivat

ive4

du/d

t

Der

ivat

ive3

du/d

t

Der

ivat

ive2

du/d

t

Der

ivat

ive1

du/d

t

Der

ivat

ive

Dem

ux

Dem

ux

Dem

ux

Clo

ck

-K- Bdz

-K- Bdy

-K- Bdx

Add

9

Add

8

Add

7

Add

6

Add

3

Add

2

Add

11

Add

10

Add

1

International Journal of Information Technology and Business Management 29

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94

Figure 8. Half ellipse position trajectory response without disturbance.

Figure 9. Half ellipse position trajectory response with disturbance.

Figure 10. PSO-based Force-Position controller block diagram.

Figure 11. First position trajectory response using PSO-based controller.

Figure 12. First position trajectory response using PSO-based controller with the presence of disturbance.

0.16 0.18 0.2 0.22 0.24 0.26 0.28 0.3 0.32-0.7

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

x axis (meter)

y a

xis

(m

ete

r)

second trajectory response

0.16 0.18 0.2 0.22 0.24 0.26 0.28 0.3 0.32-0.7

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

x axis (meter)

y ax

is (

met

er)

second trajectory

desired

actual

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8-0.7

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

0.1

z axis (meter)

y a

xis

(m

ete

r)

first trajectory response

desired

actual

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8-0.7

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

z axis (meter)

y a

xis

(m

ete

r)

first trajectory response

desired

actual

International Journal of Information Technology and Business Management 29

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95

Figure 13. Second position (half ellipse) trajectory response using PSO-based

controller and without disturbance.

Figure14. Second (half ellipse) position trajectory response using

PSO-based controller with the presence of disturbance.

Figure 16. Position trajectory response of the first test.

0.16 0.18 0.2 0.22 0.24 0.26 0.28 0.3 0.32-0.7

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

x axis (meter)

y a

xis

(m

ete

r)

second trajectory

desired

actual

0.16 0.18 0.2 0.22 0.24 0.26 0.28 0.3 0.32-0.7

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

x axis (meter)

y a

xis

(m

ete

r)

second trajectory

desired

actual

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9-0.7

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

z axis (meter)y a

xis

(m

ete

r)

trajectory response

actual

desired

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96

Figure 15. Force-Position controllers with DAQ card simulink blocks.

FX

FY

FZ

0

thi4

0

thi3

0

thf4

90

thf3

100

tf

0

t

-K-

kfz

-K-

kfy

-K-

kfx

In1

In2

In3

th1

th3

th4

interfasing system

1

fzd

0

fyd

0

fxd

MATLAB

Function

forword_kinamtics

0.17

d2

MATLAB

Function

controller_equations

0.311

a4

0.341

a3

0.16

a1

zf

To Workspace4

yf

To Workspace3

zd

To Workspace2

yd

To Workspace1

t

To Workspace

Switch2

Switch1

Switch

Step2

Step1

Step

Scope9

Scope8

Scope7

Scope6

Scope34

Scope33

Scope32

Scope31

Scope30

Scope28

Scope27

Scope26

Scope25

Scope24

Scope23

Scope22

Scope21

Scope20

Scope2

Scope19

Scope18

Scope17

Scope16

Scope15

Scope14

Scope13

Scope12

Scope11

Scope10

Scope1

Scope

Saturation2

Saturation1

signal1

signal2

signal3

signal4

signal5

signal6

signal1

signal2

signal3

signal4

signal5

signal6

signal7

signal1

signal2

signal3

signal4

signal5

signal6

signal7

signal8

signal9

signal10

signal11

signal12

signal13

signal14

signal15

2

Mdz

2

Mdy

2

Mdx

Manual Switch2

Manual Switch1

Manual Switch

MATLAB

Function

MATLAB Fcn

60

KDZ

60

KDY

60

KDX

1

Gain9

0.1

Gain8

3

Gain7

3

Gain6

2

Gain5

-K-

Gain4

-K-

Gain3

5

Gain2

2

Gain14

4

Gain13

-K-

Gain12

-K-

Gain11

-K-

Gain10

-K-

Gain1

Fuzzy Logic

Controller2

Fuzzy Logic

Controller1

Fuzzy Logic

Controller

du/dt

Derivative8

du/dt

Derivative7

du/dt

Derivative6

du/dt

Derivative5

du/dt

Derivative4

du/dt

Derivative3

du/dt

Derivative2

du/dt

Derivative1

du/dt

Derivative

Demux

Demux

Demux

D2R

Degrees to

Radians6

D2R

Degrees to

Radians5

D2R

Degrees to

Radians4

D2R

Degrees to

Radians3

D2R

Degrees to

Radians2

D2R

Degrees to

Radians1

D2R

Degrees to

Radians

0

Constant5

0

Constant4

0

Constant3

0

Constant2

0

Constant1

0

Constant

0

Clock

-K-

Bdz

-K-

Bdy

-K-

Bdx

Add9

Add8

Add7

Add6

Add3

Add2

Add11

Add10

Add1

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97

Figure 17. Position trajectory response of the second test.

Figure 18. Position trajectory response of the first test using PSO.

Figure 19. Position trajectory response of the second test using PSO.

X. REFERENCES [1] Schiele and F. C. T. Van der Helm, "Kinematic

Design to Improve Ergonomics in Human

Machine Interaction," IEEE Transactions on

Neural Systems and Rehabilitation Engineering,

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[2] S. Parasuraman, A. W. Oyong and V. Ganapathy,

"Development of Robot Assisted Stroke

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Engineering Bangalore, India, pp. 256-261, 22-25

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[3] J. Xianzhi, X. Caihua, S. Ronglei and X. Youlun,

"Fuzzy Hybrid Force-Position Control for the

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[4] J. Ueda, D. Ming, V. Krishnamoorthy, M.

Shinohara, and T. Ogasawara, "Individual Muscle

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[5] H. Mehdi and O. Boubaker, "Stiffness and

Impedance Control Using Lyapunov Theory for

Robot-Aided Rehabilitation," Springer

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Netherlands, Vol. 4, Issue 1 Supplement, pp. 107-

119 , 2012. www.ivsl.org.

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9-0.7

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

z axis (mrtr)

y a

xis

(m

ete

r)

trajectory response

desired

actual

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9-0.7

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

z axis (meter)

y a

xis

(m

ete

r)

trajectory response

actual

desired

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9-0.7

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

z axis (meter)

y a

xis

(m

ete

r)

traajectory response

desired

actual

International Journal of Information Technology and Business Management 29

th July 2015. Vol.39 No.1

© 2012-2015 JITBM & ARF. All rights reserved

ISSN 2304-0777 www.jitbm.com

98

[6] M. Y. Hassan and Z. A. Karam, "Design and

Implementation of Rehabilitation Robot for

Human Arm Movements," The Second

Engineering Conference of Control, Computers and

Mechatronics Engineering, Baghdad, Iraq, 25-27

Feb, 2014.

[7] M. W. Spong, S. Hutchinson and M. Vidyasagar,

Robot Modeling and Control, John Wiley& Sons

Inc, Edition, USA, 2005.

[8] M. Arora, T. Kaur and Chetna, "Modeling of One

Link Robot Using Friction Compensator," IJCST

Vol. 2, Issue 1, pp. 216-219, March 2011.

[9] M. Y. Hassan and Z. A. Karam, "Modeling and

Force-Position Controller Design of

Rehabilitation Robot for Human Arm

Movements," Engineering & Technology Journal,

Baghdad, Iraq, Feb, 2014.

[10] Bonilla, F. Reyes, M. Mendoza, E. J. González and

Galvan, "A Dynamic-compensation Approach to

Impedance Control of Robot Manipulators,"

Springer-Journal of Intelligent & Robotic Systems,

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[11] J. Kennedy and R. Eberhart, "Particle Swarm

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[12] X. Yang, J. Yuan, J. Yuan and H. Mao, "A

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[13] M. M. Zirkohi, M. M. Fateh and M. A. Shoorehdeli,

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Using Voltage Control Strategy," Springer -

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