Comparison of different gaits with rotation of the feet for a planar biped

Abstract

Fast human walking includes a phase where the stance heel rises from the ground and the stance foot rotates about the stance toe. This phase where the biped becomes under-actuated is not present during the walk of humanoid robots. The objective of this study is to determine if this phase is useful to reduce the energy consumed in the walking. In order to study the efficiency of this phase, six cyclic gaits are presented for a planar biped robot. The simplest cyclic motion is composed of successive single support phases with flat stance foot on the ground. The most complex cyclic motion is composed of single support phases that include a subphase of rotation of the stance foot about the toe and of finite time double support phase. For the synthesis of these walking gaits, optimal motions with respect to the torque cost, are defined by taking into account given performances of actuators. It is shown that for fast motions a foot rotation sub-phase is useful to reduce the criteria cost. In the optimization process, under-actuated phase (foot rotation phase), fullyactuated phase (flat foot phase) and over-actuated phase (double support phase) are considered.

Persistent homology for automatic determination of human-data based cost of bipedal walking

“…We next use the HBC to compute the cost of walking for bipedal robots that have been considered in the literature with no knee-lock. In [7] Fig. 11 illustrates these robotic models.…”

“…Traditionally, most models of bipedal robots have employed a single domain model [1][2][3][4], which assumes an instantaneous double support phase and usually excludes the presence of feet (models of this form began with the so-called compass gait biped, which did not have knees or feet). Adding feet to the bipedal robot results in the need to extend the domain breakdown beyond a single discrete phase, which is typically done by either adding a phase where the heel is off the ground or a double support phase where both feet are on the ground, or any combination thereof [5][6][7]. This lack of consistency among models in the literature motivates the desire to determine if there does in fact exist a single ''universal'' domain breakdown that should be used when modeling bipedal robots, especially in the context of obtaining human-like bipedal walking.…”

A model based study of a quantitative relation between joint strengthening and the highest achievable speed of human walking

“…In another group of mathematical researches, an optimization method based on robotic approach was used to study the bipedal walking. Since the normal human subject follows the natural pattern of walking, the optimization methods which emphasize on generation of optimal gait without considering any specified pattern [24][25][26][27] are not desired in modeling of human walking. Alternatively, the time optimal control approaches, which find the solution while tracking the desired path [28][29][30], are useful in this field.…”

Offline path planning, dynamic modeling and gait optimization of a 2D humanoid robot

“…To this end dynamic model of humanoid robot is calculated. From the cost calculation viewpoint, for 2D models, Lagrange or Kane method is suitable [14] but for 3D models, recursive Newton method is appropriate [15].…”