Dextrous manipulation of a micropart with multiple compliant probes through visual force feedback

Abstract

Abstract-In our recent work, we have demonstrated effectiveness of the concept of multi-probe microassembly for manipulating and inserting microscale, sub-millimeter, parts to create three-dimensional microstructures. However, the approach has been based on trial-and-error manual teaching of grasp points to ensure a stable grasp during motion. As a result, the part orientation is restricted (nearly aligned with the world reference frame and lying flat) to ensure successful grasping and manipulation. In this paper, we developed a kinematics based hybrid motion and force control based only on vision feedback. We first conduct a systematic analysis of the bending of the probes while they are in contact with the part, to estimate the grasp force based on the vision feedback of the probe configuration. A Jacobian based controller is then used for position manipulation while maintaining the desired squeeze force. Experimental results with two probes and two camera are included to demonstrate the effectiveness of the controller to move the part to specified position and orientation while maintaining sufficient squeeze force to prevent part slippage.

Path Planning for 3-D In-Hand Manipulation of Micro-Objects Using Rotation Decomposition

“…Those differences might help to reduce the complexity of dexterous in-hand manipulation, which also highly depends on the considered shapes and the number of possible contact points c . Considering simple polyhedrons such as cuboids [ 1 , 18 ], tetrahedrons, or objects with a limited number of facets has already been resolved [ 19 , 20 ].…”

Planning in-hand dexterous micro-manipulation using 3-D rotations decomposition

“…Other works consider more complex shapes but the dexterity of the proposed approaches is limited. For instance, two fingers are used in [22] to rotate a Lego-like object but the rotation angles are small since no re-grasp operation is performed. In [23], the manipulated object lays on a substrate (2-D motion) and is pushed by four probes to get to the desired object's pose.…”

Experimental validation of in-hand planar orientation and translation in microscale

“…Previous works have demonstrated the feasibility of automatic and semi-automatic handling using two [5]- [8], three [9] or four [10] probes having several degrees of freedom (DoF). However, the manipulated objects were limited to microspheres except in [9] where more complex objects have been manipulated using three probes having 6 DoF (two mobile fingers and a static one). In [11] an integrated dexterous gripper with 2 fingers having 3 DoF each was also used for micro-parts inspection.…”