Kinematics of Hex-Piderix - A Six-Legged Robot - Using Screw Theory

Abstract

In this paper the kinematic analysis of a six-legged robot, hereafter named Hex-piderix, is carried out. A three revolute (3R) chain has been chosen for each limb in order to mimic the leg structure of an insect. The rotation matrix, with unitary vectors, and the Denavit-Hartenberg (D-H) conventions are used to find the pose of the thorax. The problem of inverse position is solved by geometrical analysis. The direct and inverse infinitesimal kinematics are obtained by the reciprocal screw theory, considering a suction cup attached to each leg and modelling it as a UP linkage. A numerical example of the thorax pose was made by solving the equations obtained from the direct position analysis. The equations of the inverse position analysis were solved to obtain the angles of the joints. Finally, the velocity values of the thorax obtained from the infinitesimal kinematics were validated by simulating the movements of Hex-piderix using specialized software.

Computer aided modeling and analysis of turning motion of hexapod robot on varying terrains

“…The six-legged robot is more robust because it is able to walk with one or two failed legs (Yang 2009;Shih et al 2012), since it is possible to define stable gaits by using either four or five legs. Also, compared to eightor more-legged robots, its power consumption is less, since with the increase in the number of legs; a lot of actuators are to be controlled through a continuous coordination in addition to complicacies in kinematics and dynamics of legged mechanisms (Santos et al 2006;Sandoval-Castro et al 2013;Roy and Pratihar 2014;Akdag et al 2012). Therefore, a six-legged robot is a kind of optimal robotic structure to be used for varying terrains.…”

Hexagonal hexapod robot foot-modeled dynamics simulation analysis

“…Hexapod robot's foot-acts are variety, and the predecessors have done a lot of researches. Sandoval [4] et al study the structure of wheeled robots, but they do not study its structures. Martin [5] et al study the structure of the foot robot, but they do not study foot robot structural analysis.…”

Optimal Feet-Forces’ and Torque Distributions of Six-Legged Robot Maneuvering on Various Terrains

“…A lot of studies had been carried out by researchers worldwide related to the kinematics, dynamics, and control of six-legged robots. [1][2][3] Most of those studies were simplified to avoid the complexities involved in the robot dynamics of six-legged robots. In addition to that, the model capabilities were limited to the study of kinematics and dynamics of the system locomoting on flat terrain, 3,4 though very few simplified models in the recent past were developed for locomotion on uneven terrain.…”