MIRA University of Twente
Department of Biomechanical Engineering

Feed forward control of the LOPES (Frank Brontsema)


Frank Brontsema


Horst W210




Prof. dr. ir Herman van der Kooij (coordinator)

Dr. Edwin van Asseldonk

Nese Tufekciler Msc.

Starting date:


Frank Brontsema




Feed forward control of the LOPES, using radial basis functions


The feedback control that is momentarily used in the LOPES has a couple of disadvantages. That is why we are looking for a new type of controller that uses feed forward instead of feedback. Unfortunately there are some disadvantages to this control method too. In traditional feed forward we have to know the system that is controlled. Because of e.g. the human contribution, our system isn’t well known, and we have to use another type of feed forward control.


Make a feed forward controller for the LOPES in Simulink and test this controller on the LOPES. This method has been previously used on an arm robot and my job is to get it to work on the LOPES.


We are going to use radial basis functions to estimate the system that we want to control. This method works kind of like Fourier analysis. Here a repetitive signal is being estimated by a linear combination of sines and cosines. In our radial basis function method we estimate the force that has to be applied by the robot to the patient by a linear combination of these radial basis functions.

Further information

For more information on the method I would like to refer to

Wolbrecht, E. (2008) ‘Optimizing Compliant, Model-Based Robotic Assistance to Promote Neurorehabilitation’, IEEE transactions on neural systems and rehabilitation engineering, 16(3) 286-296