Generalized biped walking control

Abstract

Figure 1: Real-time physics-based simulation of walking. The method provides robust control across a range of gaits, styles, characters, and skills. Motions are easily authored by novice users. AbstractWe present a control strategy for physically-simulated walking motions that generalizes well across gait parameters, motion styles, character proportions, and a variety of skills. The control is realtime, requires no character-specific or motion-specific tuning, is robust to disturbances, and is simple to compute. The method works by integrating tracking, using proportional-derivative control; foot placement, using an inverted pendulum model; and adjustments for gravity and velocity errors, using Jacobian transpose control. Highlevel gait parameters allow for forwards-and-backwards walking, various walking speeds, turns, walk-to-stop, idling, and stop-towalk behaviors. Character proportions and motion styles can be authored interactively, with edits resulting in the instant realization of a suitable controller. The control is further shown to generalize across a variety of walking-related skills, including picking up objects placed at any height, lifting and walking with heavy crates, pushing and pulling crates, stepping over obstacles, ducking under obstacles, and climbing steps.

A simple controller for the prediction of three-dimensional gait

“…As indicated in the introduction, several torque actuated bipedal walkers have been developed with impressive predictive capacity (e.g. Coros et al, 2010;Yin et al, 2007). To progress in predicting orthopedic surgical outcomes, we encourage these models to be connected to state-of-the-art musculoskeletal model to show their usefulness in a clinical settings.…”

“…Particularly in the robotics field, real-time three-dimensional bipedal walkers have been developed which achieve impressive perturbation correction and can adapt to different environments (e.g. Coros et al, 2010;Yin et al, 2007). In the biomechanics field, the development of predictive musculoskeletal gait models have more focused on their clinical relevance, i.e.…”

“…Geyer and Herr, 2010), use torque actuators (e.g. Coros et al, 2010;Van der Kooij et al, 2003) or have control schemes containing many parameters (e.g. Wang et al, 2012;Yamaguchi and Zajac, 1990).…”

Optimization control for biped motion trajectory

“…[17] uses action specific controllers, with low dimensional parameter. There are also some research based on basic locomotion controllers [18][19] [20]. Optimization tunes control strategies [7], without necessarily resorting to complex analytical models of the dynamics, or careful manual tuning of parameters.…”

Interactive dynamics and balance of a virtual character during manipulation tasks

“…This simplified version is close to the JT control method. S. Coros et al [4] applied the JT control method to adjust for gravity and velocity errors in a walk controller. However, neither of them used optimization to find the solution.…”