Graduate Student Posters 2007

Author: Chao Gao

In this poster, we present the evolution of the Automated Transport and Retrieval System (ATRS) - an alternate mobility solution for drivers with lower body disabilities. The ATRS employs robotics and automation technologies, and can be integrated into a standard minivan or sport utility vehicle (SUV). At the core of the ATRS is a "smart" wheelchair system that autonomously navigates between the driver's position and a powered lift at the rear of the vehicle - eliminating the need for an attendant.

From an automation perspective, autonomously and robustly docking the wheelchair onto the lift platform presented the most significant technical challenge for ATRS. This was driven primarily by geometry constraints which limited clearance between the chair wheels and the lift platform rails. During the last three years, we have developed both a proof of concept system which employs a vision-based localization scheme, and the current Beta system which employs a LIDAR for estimating the wheelchair position. The vision-based system was capable of < 1cm position accuracy, but was not robust under extreme weather and illumination conditions. The LIDAR-based system is much more robust, finishing 300+ consecutive wheelchair traversals without failure during live demonstrations at the World Congress and Exposition on Disabilities in Nov 2006.

We are currently improving the algorithms for wheelchair position estimation and control to make the Beta system 100% reliable for docking and market launch in Sep. 2007. Also, are developing an active vision sensor which possesses both the advantages of the regular cameras (accurate and inexpensive) and the LIDAR system (robustness).