Many research works on the control of nonholonomic wheeled mobile robots (WMRs) do not consider the actuator saturation problem and the absence of velocity sensors in practice. The actuator saturation deteriorates the tracking performance of the controller, and the use of velocity sensors increases the cost and weight of WMR systems. This paper simultaneously addresses these problems by designing a saturated output feedback controller for uncertain nonholonomic WMRs. First, a second-order input–output model of nonholonomic WMRs is developed by defining a suitable set of output equations. Then a saturated adaptive robust tracking controller is proposed without velocity measurements. For this purpose, a nonlinear saturated observer is used to estimate robot velocities. The risk of actuator saturation is effectively reduced by utilizing saturation functions in the design of the observer–controller scheme. Semi-global uniform ultimate boundedness of error signals is guarantied by the Lyapunov stability analyses. Finally, simulation results are provided to show the effectiveness of the proposed controller. Compared with one recent work of the author, a comparative study is also presented to illustrate that the proposed saturated controller is more effective when WMR actuators are subjected to saturation.

Traditionally, robot motion planners use Voronoi Diagrams for generating admissible paths that connect an initial with a final configuration. When dynamic scenarios are involved, these techniques imply a heavy computational cost. The novelty of the technique presented here is that it can provide fast and particularly suitable routes without considering the full scenario if environmental changes appear. The new method is designed to work with a post-process technique in order to provide admissible paths for car-like robots coping with kinematic constraints. This new approach is capable of supplying continuous paths and also elaborate maneuvers if cluttered environments are involved.