Energy Optimality in Novel Movement: Sideways Walking

The Ohio State University Department of Mechanical and Aerospace Engineering Honors Theses
November 2012
date available 2012-11-09T20:34:17Z
http://hdl.handle.net/1811/53177

Matthew Handford

Abstract

The theory of energy optimality states that humans naturally move in a manner that minimizes the energy that their bodies use. This theory has been shown to be approximately true for natural gaits but it has not been tested on many unnatural gaits. To test if this theory would work on novel gaits, we conducted an experiment to compare people’s natural preferred speed to their energy optimal speed as they walked sideways. Subjects were asked to choose a comfortable speed using while walking sideways which was then recorded as the preferred velocity. Then, using a portable metabolic measurement system (the Oxycon Mobile VO2 device), their metabolic energy usage was recorded at a variety of speeds. Using this data, energy optimal velocities were found and compared with preferred velocities. While these quantities didn’t match exactly, a person’s preferred speed could be predicted by the population’s optimal speed with an average absolute error of 0.117 m/s. With the caveat that the subject pool was small with high data variability, the mean optimal speed (0.592 m/s) differed from the preferred speeds by only about an average of 0.041 m/s. In future experimentation, we hope to investigate the effects of perception and prior experience and the length of time it takes to reach the energy optimal speed with the subjects’ natural movement.

Keywords

Human Locomotion; Energy; Walking; Optimality

http://hdl.handle.net/1811/53177

http://kb.osu.edu/dspace/handle/1811/53177