From: Arkapravo Bhaumik <arkapravobhaumik@gm...>  20100727 08:37:59

Hi Nelson Many thanks, I will try to put it together as a program. On 27 July 2010 13:20, Nelson Goncalves <ngoncalves@...> wrote: > Hi, > > What you want is, in general, not trivial or simple to accomplish. > However there are known, simple solutions for your problem depending > on the type of drive of your robot. > > Essentially, you want a function that has as inputs: >  the position and orientation of the robot at time t, q(t) >  position and orientation of where the robot must be at time t, p(t) > > The function will then compute the output of each actuator so that > the error along the path is minimized: min \int_0^t (p(t)  q(t)) > > \int_0^t is the integral of a function from 0 up to t. > > I am making this much simpler than it is, and it is not possible to > write down a simple answer in the email without knowing more about > your robot or your background in mobile robotics. Try searching on > your local library (or the web) for "mobile robotic kinematics", > "control systems" and "path following". Often you can find simple > solutions for robots with tank like drives. > > As a final note, notice that you did not specify the orientation of > the robot along the circular path. This may seem obvious for some > types of drives, but an omnidirectional robot can be made to move > along a circle *and* spin at the same time (like a ballet dancer). > > Also if you robot as a car like drive, then there is a lower bound on > the radius of the circle it can execute. As you can see the problem > is not trivial, even though it appears simple. > > Nelson Gon\c calves > > Em Tue, 27 Jul 2010 11:42:10 +0530 > Arkapravo Bhaumik <arkapravobhaumik@...> escreveu: > > > Hi everyone > > > > I want my robot to move around in a given trajectory. Say a Cartesian > > (or Polar) curve is given and the robot executes a trajectory along > > that curve. For example if my program inputs x^2 + y^2 = 4, then my > > robot should move around the origin in a radius of 2 units. > > > > As of now, I do not have any clue as to how to put this to effect ! > > Any suggestions are welcome. > > > > Best regards > > > > Arkapravo > > > > >  > Learning to eat soup with a knife > >  > Nelson Gonçalves > http://thinkingolivetree.blogspot.com/ > > > 