Robotic Touch: From Deformable Grasping to Impulsive Manipulation
Speaker: Yan-Bin Jia, Department of Computer Science
Abstract: Robots interact with the outside world through continual or instantaneous contact. This talk will present the work from my group over the past few years on deformable grasping and impulsive manipulation — two skills important for measuring robotic dexterity, but yet seriously under-researched due to the lack of computational foundations and tools for analysis and synthesis.
Deformation of an object being grasped by a robotic hand results in a changing wrench space, growing contact areas and pointwise varying contact modes inside these areas. Grasping strategies need to shift from the traditional force-centered paradigm to one that is displacement-oriented. I will begin with an event-driven algorithm that employs two fingers to squeeze a 2D object until a grip is formed. The result is supported by a finite element analysis, and several energy-based grasp quality measures. Then I will move on to describe a strategy to pick up soft 3D objects by squeezing them until they are “felt” to be liftable, through repeated virtual tests during such a squeeze.
Our investigation on impulsive manipulation has progressed from computational modeling of simultaneous impacts with compliance to planning the pre-impact motion of a robotic manipulator in order to purposefully alter the trajectory of a moving object. A collision event with multiple impacts can be modeled as transitions among discrete states. Each state describes a different topology of the collision, and evolves under the control of a separate system of ordinary differential equations in terms of impulses subject to energy-based restitution, Coulomb friction, and compliance. The talk will end with our ongoing work on impact planning for a robotic arm to bat flying objects to a target location.
The CAM Seminar is organized in the ISU Mathematics Department. It brings speakers from inside and outside of ISU, raising issues and exchanging ideas on topics of current interest in the are of computational and applied mathematics.