Navigation and control of a trolley by using a dynamical model

This work deals with the guidance and control of the motion of a trolley. The trolley is composed from two rear wheels, each of them controlled separately, and from two front castor wheels (see Figure 1). Given N points Pi, I = 1, …, N in the horizontal plane, a finite time interval [0, tf], and a sequence of times τ1 = 0 < τ2 < < τN = tƒ. Based on a dynamical model of the trolley, and by using the concept of path controllability, a control law for the trolleyʹs rear wheels is derived, to steer the trolleyʹs center (x,y) in such a manner that (x,y) will pass through Pi at the time τi, I = 1, …, N, respectively.