top of page
Molecular lib

on-going project 2022-2023

Wearable Lifting-ASSISTIVE Device 
Design REVIEW 12/13/22

The team is developing a device that assists persons with limited upper-body muscle capacity

Features 

  • forearm/bicep cuffs

  • aluminum bar linkage

Anticipated Features

  • thread-assisted motor for adding/releasing tension

  • bump switch/limit switch/remote for control

OVERVIEW

THE CUFF

  • attachment point and security

  • material : Elastic 50A Resin

    • allows for flexibility

  • slits to hold linkage bar(s)

  • holes for threading string

  • Velcro™ to fasten to wrist/bicep

THE FIRMWARE

  • Use Zephyr Linux

    • Lightweight fast RTOS, provides standard hardware interfacing libraries

  • Uses C to create firmware

    • Complied and flashed to the RPi Pico

  • Uses RPi Pico as a “Picoprobe” device to debug code, and as a flashing device

THE MOTOR

  • RPi Pico Microcontroller

    • Small and lightweight. Still powerful enough to act as motor controller

  • L293D used as motor driver IC

    • Allows for variable voltage to be supplied and simple dual H-bridge solution

  • Battery powered

  • Bipolar Stepper Motor

    • Allows for holding torque to be applied, precision movement

THE ROADMAP

End of Next Semester

  • Functional Prototype

  • Find cheapest, most functional materials

  • Find most practical control system

Future Semesters

  • Continue making additions

  • Limit friction in pulley system

  • Make it more durable/to last

  • Test on real patients/get feedback to refine design

Design REVIEW 05/03/23

THE MINIMUM VIABLE PROTOTYPE

mvp.png

Our first prototype of the device utilizes Velcro technology to allow for easy attachment and adjustment. With the conclusion of this final meeting of the semester, the team was able to get a single trial run with the motor and battery system hooked up to the device; a small tug on the thread was achieved.

 

In Fall 2023, we will be working towards enhancing the prototype with several goals in mind:

  • Improve attachment of pulley to motor to improve effective torsional force

  • Toy with different wearable enclosures for battery and controller

  • Begin implementation of software controlling torsional force provided by motor

MOTOR ENCLOSURE​

PULLEY (FOR THREAD)​

​​

CUFF 2.0

  • Minimized material/material cost (~80%)             

  • New attachment mechanism

    • device effortlessly attaches to Velcro wraps on arm​

    • adjustable fit

    • more comfortable

bottom of page