On Fri, Nov 2, 2012 at 6:02 AM, Erik Christiansen <dva...@internode.on.net>wrote:
> On 01.11.12 18:40, Peter Blodow wrote: > > How is the position of the balls rsp. the pendulum detected? > > Peter > > My guess is that the beam pivot has a servo motor and quadrature > encoder. If the ball is off-center, then the beam pivots, unless > sufficient restoring torque from the motor is applied. The amount of > torque (current) required at any instant would then be a measure of ball > position, if the beam is not accelerating, I figure. > For that system in particular a linearized model is feasible and very light computationally, then, as you can obtain acceleration from the encoder, then you can have a model based position feedback. I would choose a Kalman filter approach, to cope with the noise in acceleration, and maybe simultaneous identification of the relevant inertia and friction parameters. You can as well use a nonlinear model (then extended Kalman filtering) for extra precision. Javier > If the pendulum is constrained to one axis of rotation, then one encoder > on the pivot is all that is needed there as well. > > Erik > > -- > In the bathtub of history the truth is harder to hold than the soap, > and much more difficult to find." - Terry Pratchett > > > > ------------------------------------------------------------------------------ > LogMeIn Central: Instant, anywhere, Remote PC access and management. > Stay in control, update software, and manage PCs from one command center > Diagnose problems and improve visibility into emerging IT issues > Automate, monitor and manage. Do more in less time with Central > http://p.sf.net/sfu/logmein12331_d2d > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ------------------------------------------------------------------------------ LogMeIn Central: Instant, anywhere, Remote PC access and management. Stay in control, update software, and manage PCs from one command center Diagnose problems and improve visibility into emerging IT issues Automate, monitor and manage. Do more in less time with Central http://p.sf.net/sfu/logmein12331_d2d _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
