Wheeled mobile robot navigation using proportional navigation

We present a method for wheeled mobile robot navigation based on the proportional navigation law. This method integrates the robot's kinematics equations and geometric rules. According to the control strategy, the robot's angular velocity is proportional to the rate of turn of the angle of the line of sight that joins the robot and the goal. We derive a relative kinematics system which models the navigation problem of the robot in polar coordinates. The kinematics model captures the robot path as a function of the control law parameters. It turns out that different paths are obtained for different control parameters. Since the control parameters are real, the number of possible paths is infinite. Results concerning the navigation using our control law are rigorously proven. An extensive simulation confirms our theoretical results.     

Kinematics-Based Navigation Functions

In this paper, we introduce a new family of navigation laws which are based on analytic navigation functions derived using the kinematics equations. These navigation laws combine local and global aspects, and can be used for both indoor and outdoor navigation. The robot's kinematics model is represented in polar coordinates. The analytic navigation functions suggested here are functions of the line-of-sight angle between the robot and the goal, and depend on one or more navigation parameters. The navigation parameters allow us to control the navigation law and, thus, the path of the robot. The choice of the navigation function and its parameters is important, and must satisfy some conditions. Different paths are obtained for different navigation functions and different parameters. This property is used to avoid collision with obstacles. Under this formulation, the number of navigation functions allowing the robot to reach a given goal is infinite. An extensive simulation study shows the effectiveness of the method.     

A robotic intelligent wheelchair system based on obstacle avoidance and navigation functions

Abstract. David Chalmers argues that a materialist theory of mind is in principle unattainable because consciousness does not logically supervene on the physical. In order to demonstrate this, he needs to make a convincing case for the conceptual possibility of zombies. His position, however, is rather tenuous due to the paradoxical nature of phenomenal judgments (among other things). That is, the fact that zombies would have to talk about consciousness and conscious experience may render them inconceivable. It is argued that this paradox is indeed fatal to his position, because zombies will never make meaningful phenomenal judgments.