A method for collision-free navigation of a wheeled mobile robot using the range-only information

We present a new guidance logic for the problem of collision-free navigation of wheeled mobile robot (WMR) towards an unknown stationary or maneuvering target based on just the relative distance between the robot and target, also known as line-of-sight range (LOS-range). With constant robot linear velocity, we use the LOS-range variation as a measure for the angle at which the robot approaches the target. Having applied the proposed steering control law, termed equiangular navigation guidance (ENG), the robot approaches the stationary or maneuvering target along a semi-equiangular spiral and eventually goes into a circular trajectory around it. Using the sensory information, ENG is then modified to augmented-ENG (AENG) in order to navigate the WMR towards the target and simultaneously avoid the obstacles on the way. AENG enables the robot to approach an unknown stationary or follow an unpredictable maneuvering target in a cramped environment, while keeping a certain distance from the target, and simultaneously preserving a safety margin from the obstacles. The performance of the guidance law and its effectiveness is confirmed with an extensive simulation study.