Generalized direction changing fall control of humanoid robots among multiple objects

Abstract

Abstract-Humanoid robots are expected to share human environments in the future and it is important to ensure safety of their operation. A serious threat to safety is the fall of a humanoid robot, which can seriously damage both the robot and objects in its surrounding. This paper proposes a strategy for planning and control of fall. The controller's objective is to prevent the robot from hitting surrounding objects during a fall by modifying its default fall direction.We have earlier presented such a direction-changing fall controller in [1]. However, the controller was applicable only when the robot's surrounding contained a single object. In this paper we introduce a generalized approach to humanoid falldirection control among multiple objects. This new framework algorithmically establishes a desired fall direction through assigned scores, considers a number of control options, and selects and executes the best strategy. The fall planner is also able to select "No Action" as the best strategy, if appropriate. The controller is interactive and is applicable for fall occurring during upright standing or walking. The fall performance is continuously tracked and can be improved in real-time. The planning and control algorithms are demonstrated in simulation on an ASIMO-like humanoid robot.

Fall on Backpack: Damage Minimization of Humanoid Robots by Falling on Targeted Body Segments

“…If a robot can step while falling, the robot can change the falling direction, and it may also be possible to change the orientation of the trunk as reported in Refs. [2,3]. Changing the location of the contact point of the foot, for example, from the heel to the toe, may also be useful for controlling the trunk orientation.…”

“…Including the bending strategy makes n more orthogonal to the ground plane. 3 ½Á denotes a 3  3 skew symmetric matrix representing a vector cross product as (26)…”

“…If during the fall the robot can hit nearby objects or persons, its primary objective would be to prevent this from happening. The robot may try to achieve this by means of changing its default fall direction, as we have reported before [2,3]. If, however, the fall occurs in an open space, a self-damage minimization strategy can attempt to reduce the harmful effects of the ground impact.…”

Perturbation recovery of biped walking by updating the footstep

“…Humanoid robots are expected to perform complex mobility and manipulation tasks in the future and it is important to ensure safety of their operation [1]. In real environment, the humanoid robot may collide with the environment or with a human unexpectedly.…”

A minimized falling damage method for humanoid robots

“…11 Then, they introduced a generalized approach to humanoid falling direction control among multiple objects. 13 Yun and Goswami addressed a new control strategy to reduce the damage to a humanoid robot during a fall named as tripod fall.…”