PolyGlove: a body-based haptic interface

Part 1: project profile

Project name

PolyGlove: a body-based haptic interface

Project short description

PolyGlove is a new kind of haptic interfaces, that try to overcome the borders of the present datagloves exploiting the EAP technology. This glove belongs to the body-based haptic interfaces, interfaces that use the user's body as force reaction base. EAPs, or better electroactive polymers, are materials that exhibit physical behaviors in response to an electrical stimulation, or vice versa, return an electrical signal in response to a physical stimulus. These materials can work as sensors and actuators, and thanks to their skills they can represent a solution at the previously mentioned limits. In this paper is presented the synthesis of a work where the EAP technology is applied into the haptic interfaces field.

People involved

Project head(s)

Prof.ssa Giuseppina Gini - User:GiuseppinaGini

Other Politecnico di Milano people

Ing. Paolo Belluco - User:PaoloBelluco

Students currently working on the project

Gabriele Valentini - User:GabrieleValentini

Part 2: project description

Introduction

This thesis project can be collocated into the robotics �eld, that science that proposes itself to integrate, in intelligent manner, perception and action [12]. Into this �eld, the speci�c subarea of research is the haptic interfaces area, where are studied solutions to address the need of interacting with remote and virtual words [2], and in special way the project belongs to the body- based haptic interfaces. Thats devices that use the user's body as the force reaction base and have the inherent characteristics of being mobile, and therefore overcame the location dependency limitation. The purpose of this thesis is design and build a dataglove able to overcame the borders of the actual haptic interfaces. These borders are linked to the technologies used for develop the interfaces, that make di�cult the integra- tion of force and tactile feedbacks into the same device. The main goal of the project is realize a device complete of force and tactile feedbacks, that at the same time guarantees wearability, comfort and movement freedom. The keyword of the solutions design is EAP, or better, the electroactive polymers technology. These new materials are plastics and gels thats show mechanical behaviors due to an electrical stimulation, and vice versa. They can be used as new kind of sensors and actuators, making possible overcame the limits of traditional technologies.

Brief description of the work

PolyGlove is the fruit of this research, a dataglove that base all his systems on the EAPs technology. The work did can be subdivided in several di�erent 1.3. Structure of the thesis 2 phase. The �rst step was a global design of the whole glove, or better, was �nd a realizable solution for all the systems needed without project it in the de- tails. For the position/motion feed is proposed the use of two polymers: a piezoelectric PVDF �lm, and a piezoresistive CE silicon. This polymers can works as sensors, producing an electrical �eld (PVDF) or presenting changes in resistence (CE). For the force feedback, is proposed a double solution of active and passive feedback. Pistons full of ERF polymers and linked to the hand's �ngers, can be driven in voltage in order to change the viscosity of the uid and to favor or obstruct the movement passively. The active side of force feedback is constituted by arti�cial tendons made of elastomer polymers. Concluding, the tactile feedback use PVDF as actuators in order to produce vibrations on the hand's palm. Special ciliary �ngertips based on IPMC can return a texture perception. In a second phase, the design and develop process of the glove is started from the posistion/motion feed system. A �rst prototype is constituted by a glove equipped with four PVDF sensors, a control system able to sampling the sensors and to send the results to the remote side via wireless connection. This control system is made by di�erent modules, in order to simplify the prototyping phase and to allow the reuse of the single modules. The brain of the system is a PIC18F2420 microcontroller equipped of an external 12 bit ADC, the wireless communications are guarantee by an XBee module, a switching voltage regulator manage the batteries and a customized sensor board process the sensors signals. When the prototype was ready, a phase of test on the glove is started. This tests were subdivided into hardware settings test, and sensor's characteriza- tion tests. The hardware tests make possible to �nd the proper con�guration of several parameters like frequency of sampling, �ltering and so on. While the practical tests have given results about sensor's behavior, showing good skills and evidencing some weak points of the system. At the end of this work, the critical conclusions have been made showing the good characteristics of piezoelectric �lms as motion sensors, and evidencing the problems of the system. In order to complete the work, the basic guide- lines of the future works are presented. This guidelines explains how to �x the problems and show the way of future developing works.

Future works

Just to give you some ideas:

• state of the art;
• preliminary studies and sketches;
• design notes and guidelines;
• link to project documents and files (you can upload them using the Special:Upload page);
• description and results of experiments;
• photos and videos (they must have been uploaded with Special:Upload before you can insert them into this page);
• link to source code of the software written for the project (you can upload it with Special:Upload);
• advice about the configuration and the use of hardware and software;
• useful internet links;
• anything else that you think is useful to describe the project or could help people who will work on it in the future. Think about what you would have liked to find clearly explained when you started your work, instead of discovering it all by yourself the hard way. (By the way, if some of those missing information belong to other pages of this wiki, please update those pages: future users will be grateful.)