Concept of a modular climbing robot

Climbing is a current challenge in robotics. Observation of vertebrate climbing proves, that in arboreal environment like on flat ground locomotion is carried out as well by the trunk as by the limbs. Thus to elucidate one extreme a trunk-driven concept was chosen as base for our design process. Often climbing robots are highly specialized machines. They only are able to move on one or two different substrates. And they often are expensive solutions, built for a special application. The climbing robot we report about is designed as a modular system. The modular idea influences all developmental areas of a mechatronic system - the mechanical, the electronic as well as the software part. By using different modules, the robot is capable to climb on different substrates made of a wide variety of materials. The mechanical demands of climbing are strong and rule the design. Substrate contact has to be established and broken actively. A sensor concept was developed, which allows for choosing relevant sensor ranges, depending on the desired type of control. The configuration described in this paper is composed of only two different module types. Due to the features of these modules, the robot is capable to climb on pipe-like structures. The speed of the robot depends on the gait chosen.