ENERGY-BASED ANALYSIS OF BIOINSPIRED MECHANISM FOR CHEETAH ROBOT LEG

Subject of Research. The paper analyzes design methods of locomotion robots on the example of high-speed, energy-efficient cheetah robot creation which is able to move over rough terrain. The paper describes a femur mechanism energy analysis of the cheetah robot leg. The operation principle is based on flexible element resonance caused by self-oscillations of the robot inertial mass. The developed design is considered as a spring-loaded inverted pendulum with the flexible element necessary to ensure the harmonic behavior of the robot body, stable interaction with the ground, absorption of impact force and recuperation of the locomotion energy. Method. We proposed the application of biomimetic methods in the design of bio-inspired robotic devices. Their essence lies in reproducing the unique qualities and characteristics of living systems, rather than only an imitation of physical configuration. The design presented in the paper imitates the dynamics of a jumping animal due to the movement harmonic nature caused by a periodic inertia force of the robot body mass. The harmonic force, which causes self-oscillations, is derived by the Lagrange dynamic equation. A generalized description of the robot dynamics is represented in the Poisson structure used in the system concept by means of the Port-Hamilton approach. Main Results. As a result of the simulation, we have obtained energy and power exchange graphs for a spring pendulum with and without external harmonic force. The same graphs with and without internal inertial force for jumping in place are given for a femur mechanism, called “minitaur”. The diagrams of dependencies between the cost of transport coefficients and the configuration of the mechanism and the spring stiffness for a running behavior are presented. Practical Relevance. The given analysis is required for determination of the amount of energy in the system, the ways of energy budget conservation, the reasons for its consumption and how it can be replenished. In the following publications, a similar analysis will be presented for the entire leg of the cheetah-robot, imitating the tibia and metatarsus bones.