This article presents the method of determining the stability limit of the vehicle (robots or electric wheelchairs) that use tracks (chain, belt) for climbing and descending stairs. Research method was conducted by modeling vehicle which is working under the influence of some elements such as geometric, mass, velocity, acceleration, , we identify some conditions which lead to tipping. | Science & Technology Development, Vol 15, 2012 DETERMINING THE STABILITY CONDITIONS OF THE TRACK-DRIVEN VEHICLE WHILE STAIR CLIMBING AND DESCENDING Pham Duc Khoi, Thai Thi Thu Ha DCSELAB, University of Technology, VNU-HCM (Manuscript Received on April 5th, 2012, Manuscript Revised November 20rd, 2012) ABSTRACT: This article presents the method of determining the stability limit of the vehicle (robots or electric wheelchairs) that use tracks (chain, belt) for climbing and descending stairs. Research method was conducted by modeling vehicle which is working under the influence of some elements such as geometric, mass, velocity, acceleration, , we identify some conditions which lead to tipping. Finally, the results of research are constraint equations in order to ensure stable operation of vehicle. Keywords: wheelchair. An alternative solution consists of a cluster 1. INTRODUCTION Nowadays, there are many kinds of mobile robots which have been used in different tasks. One of the most interesting and useful mobile robots is mobiles robot capable of climbing and descending stairs. They are powered wheelchair which greatly improve the mobility of people with disability, the robot security, reconnaissance, fire . There were many types of vehicle have been developed and still are under development to make a mobile robot capable of climbing and descending steps, slopes and stairs. The popular solutions make use of tracks, clusters of wheels, legged system. The legged systems are mentioned in [1]. Legged robots are versatile for obstacle overpassing and high mobility in difficult terrain or soil condition, but they are too complex, low speed, and low-load capacity. Trang 36 of wheels that are attached to a rotating link. A commercial available stairs-climbing wheelchair is shown in [2] where the wheel has a smaller radius of ladder height. Each cluster is combined from two or more wheels, are arranged beam (star). Each wheel within
