CONTEMPORARY ROBOTICS - Challenges and Solutions Part 12 potx

Consuming a lot of memory and calculus, this kind of control doesn’t fit, for now, to real time control, the technological structures that benefit from such control might suffer decision

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Output Feedback Adaptive Controller Model for Perceptual Motor Control Dynamics of Human 321

Fig 4 Human Body Dynamics

Notation Parameters and Variables

r(t) position of the target

y(t) position of the hand

v(t) command signal from the brain

 dead time in the nervous system from the retina to the brain

 dead time in the nervous system from the brain to the muscle

1 time constant of the brain

2 time constant of the muscle dynamics Table 1 Parameters and variables

Fig 5 Perceptual Motor Control Model

Fig 6 Experimental Equipment

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4 Experiments

Fig.6 shows the experimental equipment An indicator shows the target position, which is

driven by AC motor 1, and an operator controls a handle to follow the indicator AC motor 2

is assembled in order to generate the assisting torque for human, while it performs as load

inertia for human in this stage

Mechanical System: From the experimental results of automatic positioning control, the

transfer function of the one-link arm mechanism involving AC motor 2: G P (s) was estimated

as follows

)1(

4213)

(





s s s

Human Dynamics model: Through the experimental results, the parameters of human

dynamics model are estimated such that  0.13[s],  1 20.03[s], respectively (Saito

and Nagasaki, 2002)

Perceptual Motor Control Model: In this case, the controlled system from a side of the

output feedback controller, which is the above-mentioned series of three elements are given

as follow

4213( )

Because it has a relative order as 4 and minimum phase characteristics, PFC: F s ( )in Fig.5 is

constructed based on Theorem 1 as follows:

))(

1())(

1()(

1

2 2

s f s

s

s f s

F

)5.0)(

103.0

)5.0)(

103.0



s s

s

(32)

Results of Experiment and simulation: Experimental results for the target position r(t)=30

[degree] are shown as Fig.7 and Fig.8 And, Fig.9 and Fig.10 also shows the simulation

results for the variance of design parameter g in Eq.(13) For the variance of design

parameter of PFC, we can obtain the simulation results shown in Figs.11 and 12 In the

simulation, the other parameters in Eq.(6) are given as k(0) = 0, 0.1, g 0.009, 0.01

Although there exists some fluctuation in the experimental results obtained for 3 testers, we

can recognize that the both responses are very similar Because, by comparing between Fig.7

and Fig.9/Fig.11, the overshoots are almost same level and the damping ratio and the values

of peak time are close resemblance

Furthermore, comparing between Fig.8 and Fig.10/Fig.12, these signals also show a close

Fig 7 Experimental Result (Output: Angle)

Fig 8 Experimental Result (Input: Torque)

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4 Experiments

Fig.6 shows the experimental equipment An indicator shows the target position, which is

driven by AC motor 1, and an operator controls a handle to follow the indicator AC motor 2

is assembled in order to generate the assisting torque for human, while it performs as load

inertia for human in this stage

Mechanical System: From the experimental results of automatic positioning control, the

transfer function of the one-link arm mechanism involving AC motor 2: G P (s) was estimated

as follows

)1

(

4213)

(





s s

s

Human Dynamics model: Through the experimental results, the parameters of human

dynamics model are estimated such that 0.13[s],  1 20.03[s], respectively (Saito

and Nagasaki, 2002)

Perceptual Motor Control Model: In this case, the controlled system from a side of the

output feedback controller, which is the above-mentioned series of three elements are given

as follow

4213( )

Because it has a relative order as 4 and minimum phase characteristics, PFC: F s ( )in Fig.5 is

constructed based on Theorem 1 as follows:

))(

1(

))(

1(

)(

1

2 2

s f

s s

s f

s F

)5

.0

)(

103