In Robotics Control area we are interested in
the development of <font color="red"><b>neuromuscular-like controller (NMC)</b></font> 
technology, applications of NMC 
to rehabilitation robots and to suspension and vibration 
control for vehicles and aircraft.
<p>

An invention disclosure of the new NMC technology has been filed with 
Northwestern University in 1997.  <br>
A patent was granted. US Patent No. 6,243,624 B1, June 2001. 
<p>

This <A HREF="http://www.iis.sinica.edu.tw/~dtlee/ROBOTICS.mpg">
video demonstration </a>
was taped at the ECE Robotics Lab., Northwestern University.
It was demonstrated by Prof. Chi-haur Wu of Northwestern University.

<p>
The neuromuscular-like compliant control was modeled from studying 
the movement of primate's muscle-reflex mechanisms.  The developed 
model consists of two major mechanisms: spindle-reflex model and muscle
stiffness mechanism. The spindle-reflex model emulates the nonlinear
reflex property of biological spindle-reflex mechanism for complying to 
movements and forces. The muscle-stiffness mechanism emulates muscle 
stiffness for tracking various movements. 
<P>

Any actuator-driven system controlled by this controller will be able
to comply to any impacting force from the environment, and in the 
meantime the system will also respond to the position command.
In comparison with the existing technologies, the proposed compliant
controller will respond to any changing displacement and provide 
the compliant force for the changing motion without using ANY force 
sensor. In addition, the controlled system can adapt to a wide range 
of loads without adjusting the controller's gains and maintain its 
stability.  
<p>

We can demonstrate the following experiments using a 
PUMA560 robot and a quarter-car model: 

<UL>
<LI>DEMO#1: Involuntary Movements Control</li>

<p>
<ul>
<li> It demonstrates force following capability WITHOUT USING a force 
  sensor. The PUMA arm can now be moved freely, following human 
  operator's movement.</li> 
  <p>
<li> This can facilitate teaching process. That is, the user can hand-grab
  the end effector to any feasible position and have the position
  recorded (instead of using a teach pendant). A much faster and
  easier way of teaching.</li>
  <p>
</ul>

<li>DEMO#2: Voluntary Movements Control</li>

<p>
We want to stress here that the entire robot is COMPLIANT without
using a force sensor which is totally different from conventional 
controllers. 

<p>
<ul>
<li> It demonstrates movements with compliant capability without using 
  a force sensor.</li>
  <p>
<li> Because of its compliant capability, the arm movement may be 
  stopped temporarily if an unexpected obstacle is present on its 
  motion path and resume its motion after the obstacle is cleared.
<br>
This is an important safety feature of an industrial robot.
  </li>
  <p>
<li> This feature can be used to absorb impacting forces to a vehicle.
  </li>
  </ul>

<p>
<li>DEMO#3: Tele-Manipulating a Compliant Robot</li>
<p>
<ul>
<li> Because of the compliance provided by the muscular-like controller, 
  it possesses an embedded safety feature that will protect the 
  machine and its environment.</li>
  <p>
<li> It demonstrates how easy it is to tele-manipulate a compliant robot 
  arm or a compliant multiple-axis machine using a remote input device.</li>
  <p>
<li> The easiness of tele-manipulation and compliant capability provided 
  by the controller are very useful features for manipulating 
  rehabilitation robots or remote manipulators.</li>
</ul>
<p>
<li> DEMO#4: Active Suspension Control on a Quarter-Car Model</li>
<p>
<ul>
<li> It demonstrates an active control mechanism for suspension control.</li>
<p>
<li> The same damping feature can be used to damp various vibration 
  levels and absorb impacting forces.</li>
</ul>
<p>
<li>DEMO#5: Maneuvering of Heavy Objects</li>
<p>
<ul>
<li> It demonstrates that a human can easily maneuver a heavy object with 
  almost no effort through an input device.</li>
  <p>
<li> It demonstrates an easy control of exoskeletal suits.</li>
<p>
</ul>
</ul>

<p>
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