Undergraduate Robotics Undergraduate Robotics atat

Roger Williams UniversityRoger Williams University

Matthew SteinRoger Williams Unversity

Never Heard of it?

Just 20 minutes south

Undergraduate Institution

B.S. General Engineering

One elective course in Robotics

Employ 1-2 students on internally fundedResearch projects

The Robotics Class

3 CreditsSr/Jr engineers and computer

scientists21 Students Fall 2006Entertaining video

Research projects?Like What?PumaPaint 1998-2008

50,000 users - thousands of paintings

Allows user to perform 2D taskLimited to a plane ( canvas)Internet surfers control robot through

a graphical user interface.Limited to simple camera feedback

Most Recent Project

J.P Brice2008 GraduateOn to U. of UtahSlides from his ASME DETC

presentation

Objective

3D manipulationLet users manipulate object instead of

drawing on a canvas

Provide more information to the user.

Provide touch feedback True haptic feedback using a force

feedback controller or sensory substitution through a GUI

iHandsRobotic hand that let internet users

manipulate objectsPlatform mounted on a linear stage

with 1 foot of displacementTwo pair of fingers

Sensors provide touch feedback

A pneumatic thumb

Hardware and circuitry controlled by Galil Inc. DMC motion controllerOnline 24x7: http://ihands.rwu.edu

Right now

Fingers

Provide touch feedbackSkin over skeletonSensors to detect touching.

Reproduce open-close motion of actual finger

Lead screw linear actuator 12V dc motor

Skin structure

Four segments for upper fingerFirst two segments cover first and

second phalangesRigid and used for pressing and gripping

Three segments for lower fingersFirst segment is also rigid and covers

first phalanx.

Skin structure (continued)

Third and fourth segment cover the third phalanxRetractable skin

PVC piece with ½ inch linear displacementSensorsSpring

Rotating tip

Third Phalanx

Finger controlSwitch at each end of linear actuator

To eliminate drift over long term operationTo prevent motor from over heating at end of

travel

Encoder on motor shaft Allows position controlEncoder feedback automatically handled by

Galil Software

Motor control

Use of motor command signal from DMC panelLinear transistor circuit to amplify

signal current from 3mA.

Finger motion

Sensory Substitution

Detect contactSkin retracts and obstruct optical sensorOp amp circuit to decide when touching or not

Display contact through graphical user interface

Red arrows are displayed on the GUI

Thumb Design

3 state opposable thumbPneumatic actuator moves thumb up

and downTransistor circuit control valveOutput port on DMC panel used to

activate thumbAll the way upAll the way downTouching and applying quick pressure

Drawings of Thumb

The Graphical User Interface

Conclusion / future work

Users have manipulated balloons and clay

Slow access ( about 2 users per day)

System is robust. Operated without need to reset for six monthsGUI an interesting research issue