The KCLBOT: A Double Compass Self-Localizing Maneuverable Mobile Robot

The key to autonomous mobile-robot navigation is effective path planning and accurate self-localisation. The lack of self-localisation or inaccurate self-localisation makes any nonholonomic autonomous mobile robot blind in a navigation environment and will deter the robot’s ability to complete path following. In the last several years, many different systems have been considered for self-localisation, from using visual odometry to using a satellite triangulation method, better known as a global position system or GPS. All of these have benefits and detriments, the solution proposed here endeavors to offer more benefits than detriments, utilizing a novel method for self-localisation, employing a dual bearing finder digital compass configuration to resolve the relative location of an autonomous nonholonomic wheeled mobile robot. To facilitate the novel hybrid method, the utilization of the mobile robot’s multiple sensors, dual wheel quadrature shaft encoders and the digital compasses are required. To support the hardware requirements of the novel localisation methodology, the cutting edge technology of a 200 MHz 32-bit ARM 9 processor on a GHI ChipworkX module are employed. The software architecture is based on the Microsoft .NET Micro Framework 4.1 using C# and the Windows Presentation Foundation (WPF). Without the inputs from the dual compass configuration it would not be possible to solve the relative position of the mobile robot analytical. Without the dual compass configuration only a numeric solution is possible, which decelerates the localisation process. The mobile robot’s digital compasses are marked with unnatural markers, for faster identification by an overhead camera. Using the overhead camera tracking results and comparing the telemetry collected by the mobile robot, using the analytical equations, the validation of this method is proven. The most fundamental part of implementing a successful maneuverable nonholonomic mobile robot is accurate self-localisation telemetry. The biggest concern about using a self-localisation technique is the amount of computation it will require to complete the task. Ideally, having an analytical solution to position offers the benefit of a single solution, where the numeric solution has many solutions and requires more time and computation to derive the solution. The benefit of the dual compass configuration is that it offers an analytical solution to the hybrid model that utilizes quadrature shaft encoders and digital compasses. This methodology evidently presents a novel approach where visual odometry is not possible.Copyright © 2011 by ASME