Control system for a grasping device

Patent metadata

Field	Value
Publication number	US-9730815-B2
Application number	US-201514929800-A
Country	US
Kind code	B2
Filing date	Nov 2, 2015
Priority date	Nov 22, 2010
Publication date	Aug 15, 2017
Grant date	Aug 15, 2017

Abstract

A method for operating a grasping device and grasping devices therefrom are provided. The grasping device is configured to use a plurality of parallel, bi-directional state flow maps each defining a sequence of poses for a plurality of joints in the grasping device. The method include receiving at least one control signal, determining a current pose of the grasping device within the one of the plurality of state flow maps currently selected for the grasping device, and selectively actuating the plurality of joints to traverse the sequence of poses, where a direction for traversing the sequence of poses is based on the at least one control signal.

First claim

What is claimed is:

1. A method for operating a grasping device using a plurality of parallel, bi-directional state flow maps each defining a sequence of poses for a plurality of joints in the grasping device, the method comprising:
receiving at least one control signal;
determining a current pose of the grasping device within the one of the plurality of state flow maps currently selected for the grasping device; and
selectively actuating the plurality of joints to traverse the sequence of poses, wherein a direction for traversing the sequence of poses is based on the at least one control signal,
wherein a first of the plurality of state flows comprises a sequence comprising a platform pose with the thumb in repose, a pointing pose, a hook pose, and a lateral pinch pose, wherein prior to the selective actuating of the plurality of joints, the method further comprises ascertaining whether the at least one control signal is a transition signal and, when the at least one control signal is a transition signal and the current pose is a transition pose within the one of the plurality of state flow maps, selecting a different one of the plurality of state flow maps for the grasping device, and wherein the switching between state-flow maps is based on a discrete switching signal.

2. The method of claim 1 , wherein the discrete signal comprises a co-contraction of musculature as detected by one or more electromyogram (EMG) signal channels.

3. A method for operating a grasping device using a plurality of parallel, bi-directional state flow maps each defining a sequence of poses for a plurality of joints in the grasping device, the method comprising:
receiving at least one electromyogram (EMG signal);
obtaining a current mechanical state of the grasping device, a current state flow map from the plurality of state flow maps, and a current position of the grasping device within the current state flow map; and
actuating the plurality of joints to transition to at least a next pose in the sequence of poses in a selected direction based on the at least one EMG signal,
wherein the sequence of poses for one of the plurality of state flow maps comprises a platform pose with the thumb in repose, a pointing pose, a hook pose, and a lateral pinch pose.

4. The method of claim 3 , wherein the actuation further comprises:
detecting an object between the plurality of joints;
actuating the plurality of joints to transition to a grasping configuration for the at least next pose.

5. The method of claim 3 , wherein prior to actuating the plurality of joints, the method further comprises:
determining whether the at least one EMG signal is a transition signal; and
if the at least one EMG signal is a transition signal and a transition is allowed at the current position of the grasping device with the current state flow map, transitioning to a different one of the plurality of state flow maps.

Assignees

• Univ Vanderbilt

Inventors

• Goldfarb Michael
• Dalley Skyler A
• Varol Huseyin Atakan

Classifications

• B25J9/02

  characterised by movement of the arms, e.g. cartesian coordinate type (B25J9/06 takes precedence) · CPC title

• B25J15/10

  with three or more finger members {(B25J15/0009 takes precedence)} · CPC title

• A61F2002/7625

  for measuring angular position · CPC title

• A61F2002/764

  for measuring acceleration · CPC title

• A61F2/70 Primary

  electrical · CPC title