An approximate stance map of the spring mass hopper with gravity correction for nonsymmetric locomotions
Author
Arslan, Ömür
Saranlı, Uluç
Morgül, Ömer
Date
2009Source Title
2009 IEEE International Conference on Robotics and Automation
Print ISSN
1050-4729
Publisher
IEEE
Pages
2388 - 2393
Language
English
Type
Conference PaperItem Usage Stats
141
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144
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Abstract
The Spring-Loaded Inverted Pendulum (SLIP) model has long been established as an effective and accurate descriptive model for running animals of widely differing sizes and morphologies, while also serving as a basis for several hopping robot designs. Further research on this model led to the discovery of several analytic approximations to its normally nonintegrable dynamics. However, these approximations mostly focus on steady-state running with symmetric trajectories due to their linearization of gravitational effects, an assumption that is quickly violated for locomotion on more complex terrain wherein transient, non-symmetric trajectories dominate. In this paper, we introduce a novel gravity correction scheme that extends on one of the more recent analytic approximations to the SLIP dynamics and achieves good accuracy even for highly non-symmetric trajectories. Our approach is based on incorporating the total effect of gravity on the angular momentum throughout a single stance phase and allows us to preserve the analytic simplicity of the approximation to support our longer term research on reactive footstep planning for dynamic legged locomotion. We compare the performance of our method in simulation to two other existing analytic approximations and show that it outperforms them for most physically realistic non-symmetric SLIP trajectories while maintaining the same accuracy for symmetric trajectories. © 2009 IEEE.
Keywords
Analytic approximationComplex terrains
Correction schemes
Descriptive Model
Footstep planning
Hopping robots
Legged locomotion
Nonsymmetric
Slip dynamics
Spring loaded inverted pendulums
Spring mass
Stance phase
Total effect
Animals
Biped locomotion
Infrared detectors
Machine design
Robotics
Robots
Trajectories