go_away

Author Topic: Nonholonomic constraints in Matlab Simmechanics  (Read 2014 times)

0 Members and 1 Guest are viewing this topic.

Offline archirdTopic starter

  • Beginner
  • *
  • Posts: 2
  • Helpful? 0
Nonholonomic constraints in Matlab Simmechanics
« on: March 30, 2009, 07:21:39 AM »
Hello there,

Recently I am trying to give a simple (at least conseptually) nonholonomic
constraint to a simple two wheeled cart module which will become sub module of serial robot.
The constraint is that there will be no side slip, i.e. the lateral velocity
of the cart will be zero.

For example let (x,y,theta) be the x coordinate, y coodrinate and orientation
of the cart with respect to the inertial fixed frame ,respectively.
Then the constraint becomes: xdot*cos(theta)=ydot*sin(theta)

Do you know how to define this constraint?

Thanks

Offline Admin

  • Administrator
  • Supreme Robot
  • *****
  • Posts: 11,659
  • Helpful? 169
    • Society of Robots
Re: Nonholonomic constraints in Matlab Simmechanics
« Reply #1 on: May 07, 2009, 06:49:02 PM »
Quote
the lateral velocity of the cart will be zero.
Do you know how to define this constraint?

xdot=0
xdotdot=0

Offline archirdTopic starter

  • Beginner
  • *
  • Posts: 2
  • Helpful? 0
Re: Nonholonomic constraints in Matlab Simmechanics
« Reply #2 on: May 13, 2009, 12:45:13 AM »

xdot=0
xdotdot=0

I suppose you mean xdot=0 and xdotdot=0 in "local body coordinate frame". Is is it possible to give
constraints in body coordinate frame?

Thanks

Offline Admin

  • Administrator
  • Supreme Robot
  • *****
  • Posts: 11,659
  • Helpful? 169
    • Society of Robots
Re: Nonholonomic constraints in Matlab Simmechanics
« Reply #3 on: May 13, 2009, 08:26:34 AM »
hmmmm what is a local body coordinate frame, as opposed to just a body coordinate frame?

I assume you'd need to know the transform . . .

 


Get Your Ad Here

data_list