On Ballistic Walking Locomotion of a Quadruped

Abstract

This paper investigates ballistic motions in walking quadrupeds on a horizontal plane. The study is carried out on a quadruped consisting of a body and four identical two-link legs. Each leg has a knee joint and is connected to the body by a haunch joint. Three types of quadruped gaits, bound, amble, and trot, are studied. None of these gaits complies with a flight phase, but they all involve simultaneous and identical motion of two legs. Muscle activities are commonly believed to alternate with periods of relaxation. Our study, therefore, assumes that the swing phase is ballistic, i.e., no active control torque is exerted. Ballistic motion is achieved through appropriate initial velocities. These velocities result from impulsive active control torques and ground reactions exerted at the boundary instants of the single support phase. Natural ballistic motions are shown to exist for the three gaits and for each valid walking velocity class. Torque cost analysis shows that amble and trot gaits are more efficient than bound.

Modeling and Experiments of Untethered Quadrupedal Running with a Bounding Gait: The Scout II Robot

“…To determine the parameters in (9), namely As can be seen from Fig. 9 (left), the simple battery model described by (9) Motor/Amplifier Model. As was mentioned above, actuator constraints are dominant in Scout II's motion and ignoring them not only results in a large discrepancy between simulation and experimental data but, most importantly, may also result in failure of the simulation model to converge to stable cyclic bounding motion.…”

“…Although many models for open or closed loop dynamic legged locomotion have been studied (e.g. [4], [9], [15], [31], [34]), and many simulation techniques have been proposed for efficient integration of the dynamic equations and visualization of the resulting motion (e.g. [10]), no models exist in the literature which are experimentally validated down to the actuator torque level.…”

Compound locomotion control system combining crawling and walking for multi-crawler multi-arm robot to adapt unstructured and unknown terrain

“…There are several gait patterns can be used for quadruped walking, such as crawl gait, pace gait, trot gait and bounce gait [18]. Usually, when passing through rough terrain, the robot will not move fast, so crawl gait is thus suitable for controlling these four legs [23]. Except the support of arms, there are still at least four stable support points made by four moveable crawlers.…”

Multilocomotion Robot: Novel Concept, Mechanism, and Control of Bio-inspired Robot

“…It is known that there are several gait pattern in quadruped walking, such as crawl gait, pace gait, trot gait, bounce gait, and gallop gait [13]. Crawl gait is the walking pattern employed by mainly most of the animals ambulating at low velocity, such as reptile and amphibian.…”