The limitations of rigid #ngertips in the precise and algorithmic study of manipulation have been discussedin many works, some dating back more than a decade. Despite that fact, much of the work in dexterous manipulation has continued to use the #point-contact" model for #nger-object interactions. In fact, most of the existing tactile sensing technologies are not adaptable to deformable #ngertips. In this work we report on experimental results obtained with a deformable tactile sensor whose properties are well-suited to manipulation. The results presented here show that the sensor described provides a rich set of tactile data. 1 Introduction In this work we describe a deformable image-based tactile sensor whose output is an approximation of the tactile surface itself. We present a set of basic tactile sensing experiments designed to demonstrate aspects of the sensor's performance. The ability of our sensor to deform while accurately localizing contact#s# makes it a promising tool fo...

Abstract — The first part of this paper describes the development of a humanoid robot hand based on an endoskeleton made of rigid links connected with elastic hinges, actuated by sheath routed tendons and covered by continuous compliant pulps. The project is called UB Hand 3 (University of Bologna Hand, 3rd version) and aims to reduce the mechanical complexity of robotic end effectors yet maintaining full anthropomorphic aspect and a good level of dexterity. In the second part this paper focuses on the early experiences of the UB Hand 3 in performing manipulation tasks.

xi 1 Introduction 1 1.1 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1.2 Main Contributions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.3 Overview of Methodology . . . . . . . . . . . . . . . . . . . . . . . . 4 1.4 Thesis Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2 Related Past Work 10 2.1 Robotic Manipulation of Deformable Objects . . . . . . . . . . . . . . 11 2.2 Control of Compliant Manipulators . . . . . . . . . . . . . . . . . . . 16 2.3 Manipulator Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 2.3.1 Compliant Manipulators . . . . . . . . . . . . . . . . . . . . . 18 2.3.2 Robot Grippers for Compliant Objects . . . . . . . . . . . . . 19 2.4 Deformable Objects in Computer Vision and Graphics . . . . . . . . 20 2.5 Summary of the Literature . . . . . . . . . . . . . . . . . . . . . . . . 24 3 Deformable Object Model 27 3.1 Deformable Object Representation . . . . . . . . . . . . . ....

Recently developed experimental and numerical environments have helped breathe life into the various control theories found in textbooks and have thereby greatly changed the educational experience of students of automatic control. Nonlinear balance beams, inverted pendulums, and distributed parameter thermal systems are now widely available for hands-on experimentation. Many students react quite positively to this additional dose of realism. Because the models selected for such experiments are usually accurately described by relatively simple differential equations, the laboratory experience reinforces both the textbook analysis and the value of numerical simulation. At the same time, there is a growing realization among educators and employers that students of automatic control should be encouraged to think of the subject in broader terms. The systems approach should embrace communica-

Abstract — Grasping of objects by robotic hands in unstructured environments demands a sensor surface that is durable, compliant, and responsive to various force and slip conditions. A compliant and robust skin can be as critical to grasping objects as the sensor it protects. In an effort to combine compliant mechanics and robust sensing, a biomimetic tactile sensor is being developed. Deformations of its skin can be detected by displacing a conductive fluid from the vicinity of electrodes on a rigid core. In this study, we used simplified finite element models to understand the effects of various textures for the inner surface of the skin and then produced the more promising textures by molding the elastomeric skin material against negatives made by stereolithography. The impedance vs. force relationships obtained with these molded skins had the predicted and desired wide dynamic range. By selecting the appropriate materials for the skin and fluid, previously described problems with hysteresis and diffusion losses have been greatly reduced. I.