New tripod walking method for legged inspection robot

Since the beginning of industrial age, more plants were founded in order to serve the demand of the economic growth. Along with more bridges were built to connect different cities together in order for a more convenient transportation. As years passed by, all of those facilities have became old which mean regular maintenance are required. We started the limb mechanism project almost 20 years ago aiming to deliver the new way of inspection and maintenance to the industrial field. The first prototype robot is called ASTERISK, a six limbs robot. ASTERISK's capabilities include walking on ceiling underside, climbing up and down stairs and ladders, tightrope walk, walk on rough terrains. To walk anti-gravity, ASTERISK is equipped with Electromagnets. Unfortunately, due to the number of degree of freedom and the previous walking program, ASTERISK could not walk in tripod mode with the operating Electromagnet. As per a result, ASTERISK could not achieve its full potential walking. The goal of this paper is to upgrade the ability of ASTERISK. It should be able to walk anti-gravity under the ceiling in tripod mode, which is faster and more natural compare to the last version. As per a result, our research will increase one passive degree of freedom, which mean we will not install actuator to increase the degree of freedom. Moreover, we will develop a new tripod walking pattern which could work with an operating Electromagnet. Our hypothesis is that with the ball joints and our new proposed walking method, ASTERIAK will be able to walk anti gravity in tripod mode under the ceiling.