Nearcontact grasping strategies from awkward poses: When simply closing your fingers is not enough * Grasping a simple object from the side is easy xe2x80x94 unless the object is almost as big as the hand or space constraints require positioning the robot hand awkwardly with respect to the object. We show that humans xe2x80x94 when faced with this challenge xe2x80x94 adopt coordinated finger movements which enable them to successfully grasp objects even from these awkward poses. We also show that it is relatively straight forward to implement these strategies autonomously. Our humanstudies approach asks participants to perform grasping task by either xe2x80x9cpuppetteeringxe2x80x9d a robotic manipulator that is identical (geometrically and kinematically) to a popular underactuated robotic manipulator (the Barrett hand), or using sliders to control the original Barrett hand. Unlike previous studies, this enables us to directly capture and compare human manipulation strategies with robotic ones. Our observation is that, while humans employ underactuation, how they use it is fundamentally different (and more effective) than that found in existing hardware.

ContactGrasp: Functional Multifinger Grasp Synthesis from Contact Grasping and manipulating objects is an important human skill. Since most objects are designed to be manipulated by human hands, anthropomorphic hands can enable richer humanrobot interaction. Desirable grasps are not only stable, but also functional: they enable postgrasp actions with the object. However, functional grasp synthesis for high degreeoffreedom anthropomorphic hands from object shape alone is challenging. We present ContactGrasp, a framework for functional grasp synthesis from object shape and contact on the object surface. Contact can be manually specified or obtained through demonstrations. Our contact representation is objectcentric and allows functional grasp synthesis even for hand models different than the one used for demonstration. Using a dataset of contact demonstrations from humans grasping diverse household objects, we synthesize functional grasps for three hand models and two functional intents. The project webpage is https:contactdb.cc.gatech.educontactgrasp.html.