Exploiting human walking speed transitions using a dynamic bipedal walking robot with controllable stiffness and limb coordination

1991 ◽

Author(s):

Karen Martin ◽

Mark Reuber

Keyword(s):

Walking Speed ◽

Design For Manufacturing ◽

Bipedal Walking ◽

Human Walking ◽

Walking Robot ◽

Walking Machine ◽

Start Up ◽

Final Weight ◽

Computer Controlled ◽

Structural Parts

Abstract This paper describes the design, fabrication, and testing of “Bigfoot,” a bipedal walking machine designed to optimize speed, cost, and ease of assembly. Bigfoot walks at near-human walking speed (0.24 m/s), can be assembled/disassembled in two hours, and has a programmable, computer-controlled start-up procedure. Design for manufacturing and assembly techniques (DFMA) were used to reduce the final weight of the robot to 12 kg, the number of structural parts to 39 individual pieces held together with 50 fasteners, and the final robot cost to $300.

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Study of Symmetric Solutions of an Underactuated Bipedal Robot

Volume 4A: Dynamics, Vibration, and Control ◽

10.1115/imece2018-87723 ◽

2018 ◽

Author(s):

Prachi Shah ◽

Vivek Sangwan

Keyword(s):

Energy Efficiency ◽

Walking Speed ◽

Solution Space ◽

Bipedal Walking ◽

Walking Robot ◽

Bipedal Robot ◽

The Past ◽

The Family ◽

Two Parameter ◽

Selection Of

Underactuated bipedal walking has been intensively studied for the past few decades and several methods have been proposed to design trajectories; however, quickly generating trajectories with varying speeds remains a challenge. One solution is to have a library of trajectories precomputed from which a new one can be picked or constructed quickly based on specific requirements. For this to become feasible one needs to develop a good understanding of the solution space. This is non-trivial for a non-linear hybrid system such as a walking robot. The goal of this study is to explore a two parameter solution space of simple underactuated biped, under a specific virtual constraint, used in literature, to enforce a symmetric gait. The family of feasible walking solutions identified is further evaluated for performance and energy efficiency. This analysis can potentially facilitate quick selection of walking trajectories for meeting specific walking speed and efficiency requirements.

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Walking Stability of a Variable Length Inverted Pendulum Controlled with Virtual Constraints

International Journal of Humanoid Robotics ◽

10.1142/s0219843619500403 ◽

2019 ◽

Vol 16 (06) ◽

pp. 1950040

Author(s):

Qiuyue Luo ◽

Christine Chevallereau ◽

Yannick Aoustin

Keyword(s):

Periodic Motion ◽

Inverted Pendulum ◽

Walking Speed ◽

Center Of Mass ◽

Pi Controller ◽

Variable Length ◽

Bipedal Walking ◽

Human Walking ◽

Walking Gait ◽

Switching Condition

Bipedal walking is a complex phenomenon that is not fully understood. Simplified models make it easier to highlight the important features. Here, the variable length inverted pendulum (VLIP) model is used, which has the particularity of taking into account the vertical oscillations of the center of mass (CoM). When the desired walking gait is defined as virtual constraints, i.e., as functions of a phasing variable and not on time, for the evolution of the swing foot and the vertical oscillation of the CoM, the walk will asymptotically converge to the periodic motion under disturbance with proper choice of the virtual constraints, thus a self-stabilization is obtained. It is shown that the vertical CoM oscillation, positions of the swing foot and the choice of the switching condition play crucial roles in stability. Moreover, a PI controller of the CoM velocity along the sagittal axis is also proposed such that the walking speed of the robot can converge to another periodic motion with a different walking speed. In this way, a natural walking gait is illustrated as well as the possibility of velocity adaptation as observed in human walking.

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