This paper illustrates the application of recent research in region-of-attraction analysis for nonlinear hybrid limit cycles. Three example systems are analyzed in detail: the van der Pol oscillator, the “rimless wheel”, and the “compass gait”, the latter two being simplified models of underactuated walking robots. The method used involves decomposition of the dynamics about the target cycle in...

In parametric excitation walking, up-and-down motion of the center of mass restores mechanical energy and sustainable gait is generated. Not only walking performance but also walking ability strongly depends on the reference trajectory of the center of mass. In this paper, we propose an optimization method for the reference trajectory, in which the reference trajectory is confined to the quarti...

Abstract Age, walking speed, the presence of problems, slope ground, and many other parameters affect human gait. Understanding gait variations obtaining a reference behavior under different conditions is important for identifying abnormal behaviors designing assistive devices, orthoses, prostheses. Predictive dynamics can be used to determine motion given task. In predictive approach, generate...

This paper is an introductory tutorial for numerical trajectory optimization with a focus on direct collocation methods. These methods are relatively simple to understand and effectively solve a wide variety of trajectory optimization problems. Throughout the paper we illustrate each new set of concepts by working through a sequence of four example problems. We start by using trapezoidal colloc...

Accurate predictive simulations of human gait rely on optimisation criteria to solve the system’s redundancy. Defining such is challenging, as objectives driving optimization are unclear. This study evaluated how minimising various physiologically-based (i.e., cost transport, muscle activity, head stability, foot–ground impact, and knee ligament use) affects predicted gait, developed a combined...

Title of Thesis: DESIGN, ANALYSIS, AND FABRICATION OF A SNAKE-INSPIRED ROBOT WITH A RECTILINEAR GAIT Degree Candidate: Brent William Spranklin Degree and Year: Master of Science, 2006 Thesis Directed By: Associate Professor Satyandra K. Gupta Department of Mechanical Engineering Snake-inspired robots display promise in areas such as search, rescue and reconnaissance due to their ability to loco...

This paper proposes a novel decision system for segregation of five normal gait phases (stance, heel-off, swing 1, swing 2 and heel-strike) by using a real-time wireless smart shoe. The classification method employed four force sensitive resistors to measure the force underneath a foot, together with an inertial measurement unit that is attached at the back of the shoe to determine the magnitud...