Five-legged Robot Platform for Hardware Simulation

In both biology and in legged robotics terrain and environmental factors play an important role in informing movement. Organisms must be well adapted to produce stable gaits in unreliable terrains and robots must be carefully designed to meet the challenges of their surroundings. Previous research has investigated how terrain and environmental factors affect the biomechanics of gait; however, little research has focused on investigating under what conditions systems favour various numbers of limbs (i.e. 3-5 legged configurations in this case), and if there exist conditions under which a preference for asymmetrically mounted limbs or gaits presents itself. To address this, the goal of this work is to develop a five-legged robot platform for hardware simulations. Presently, we have developed a functional quadrupedal prototype alongside designs for the fabrication and implementation of the fifth leg. The prototype’s legs are a system of links allowing it to move through an imitation of a natural range of movement (i.e. ground contact, ground clearance and forward swing) while being singly actuated, a design choice made to limit control complexity. Each leg is actuated by a 6V 210RPM motor which enables a variety of three-to-four-legged gait patterns. Currently, the robot produces forwards motion through a diagonal gait generated by two pairs of signals from the motor controller and informed by encoder data. The design of this robotic platform and the hardware simulations it facilitates will serve to inform the design of other robots in its field of legged robotics. Additionally, a better understanding of the effects of terrain on gait will support the design of lower-limb prosthetics and mobility devices. Investigating these fundamental questions of locomotion also serves as an avenue to answer questions in biology regarding the evolution of legged locomotion.