DESIGN AND FABRICATION OF A QUADRUPED ROBOT

Abstract

Legged robots represent a class of ground robots that make use of articulated linkages and specific control systems to move about. Compared to wheeled robots, legged robots can exploit discontinuous pathways and isolated footholds with great efficiency, thereby increasing their reach ability. In animals, legged locomotion is also highly energy efficient in addition to being dexterous and agile. Legged locomotion is fundamentally periodic in nature with well-defined flight and stance phases in each gait cycle; this cyclic nature is exploited to increase energy efficiency in all legged creatures. These gaits can be utilized differently with respect to the terrain that is explored. These benefits make legged locomotion and design of legged robots an interesting field with promising benefits. In this report, a quadruped robot based on the gait of quadruped mammals is presented by utilizing a five-bar mechanism for mimicking the natural gaits of the animals. Five-bar mechanism is used and is connected directly to the actuator for greater stability and power transmission. A robust mechanical assembly is designed and structurally improved for reduced mass and inertia. The system is tested with several motor placements in the design phase and their performance has been evaluated and their merits and demerits are gauged. The actuators are chosen based on torque calculations. After several iterations, the mechanical design is finalized. This is followed by the design of a complete electrical system. Finally, simulation is performed on Simscape Multibody to visualize walking gait of quadruped locomotion. Further experiments may be conducted to further study the legged mechanism for different gaits on a planar test bed for planar walking and running motion in addition to the effects of the underlying dynamics dictated by leg for static and dynamic stability. In addition, different gaits will be applied using control system.