Robotic Leech

Design of an optimally compliant robotic structure in a miniaturized ensemble is quite challenging. Size-optimized compliant robotic devices are of importance from the perspective of practical applications, such as internal inspection of pipes in industries. Unlike inspection and surveillance over the external exposed surfaces, autonomous surveillance over the internal surfaces of the pipes is extremely critical, and often it becomes quite risky to have humans involved for such a task. Barring the size effect, the intricacies of the mechanical design for such a miniature robot gadget needs careful attention and cohesion with respect to its pre-programmed navigation. This chapter brings out three crucial functional sub-assemblies of such a miniaturized robotic system, christened as ‘Compliant Universal Robotic Leech’ ( CURL ) ~ developed in two versions chronologically. Our customized robotic leech is a miniature robot with intention of being operated inside cylindrical pipes in the horizontal plane, having an inner diameter less than 75 mm. The actuation of CURL , including grasping of small-sized objects inside the pipe is made realizable through either of the two sub-systems, namely: rolling segment or crawling segment, and electro-mechanical-type parallel-jaw gripper segment. Being a maiden effort, the first two sets of prototypes of the robotic leech were realized with novel rigid but slender linkage-based mechanisms. Facets like tare weight, driving power, and size and shape of the prototype CURL have been considered in the optimized design and an evolutionary approach has been utilized for the hardware manifestation of this customized compliant robotic system. The prototype robotic leech is wired control, and the device is capable of transmitting the visuals of the surveillance environment through a tailor-made graphical user interface. Performance of the developed leech robot was tested through successive locomotion of the device, both in the forward and backward directions, inside straight as well as curved pipes on horizontal planes.