Spring 2017 Prosthetic Hand: Final Document

The Robot Company | CEO Professor Gary Hill

Blog Post Created by Project Manager | Bianca Esquivel

Mission, Systems, and Test Engineer | Chris Bautista Electronics and Control Engineer | Forest Nutter

Design and Manufacturing Engineer | David Mendoza

Table of Contents

Executive Summary

By Project Manager | Bianca Esquivel

Project Objective

There are 3 main project objectives that address the problem of the customer being born without a right hand and cater to his preferred recreational activities:

Being able to operate a computer mouse, specifically being able to right click and left click.

  • Ability to scroll is a plus.

Being able to pick up and drink a cup of water.

  • Ability to pick up thin/fragile paper cup is a plus.

Being able to pick up and eat a chips ahoy cookie without breaking the cookie.

  • Ability to pick up and eat a sun-chip without breaking the chip is a plus.

Mission Profile

Mission Profile from Start to Finish:

  • Customer will sit down at a desk in front of a computer with a cup of water and a plate of cookies within the reach of his prosthetic hand
  • The computer will have a game of minesweeper ready to play
  • With the prosthetic hand he will be able to operate the mouse to play minesweeper and reset the game if he should lose or restart the game should he win
  • He will be able to grasp the cup of water within his reach to drink from at his leisure without crushing the cup
  • He will be able to rotate his wrist and grasp a chips ahoy cookie within his reach and eat one at a time at his leisure without crushing the cookie

The Design

  • Complements the measurements of the customer
  • No force sensors are included in the thumb therefore, it isn’t included in the picture
  • Tips of the fingers are equipped with force sensors and rubber tips to help with gripping objects

Project Features

  • Rubber fingertips for better gripping capabilities
  • Force Sensors for a more controlled grip
  • Flex Sensors used to control the grip with the use of the toes
  • PLA Material due to project budget

System Design

By Mission, Systems, and Test Engineer | Chris Bautista

Electronics Design

by Electronics and Control Engineer | Forest Nutter

Electronics Custom Parts

TB6612FNG

Motor Driver Requirements Needed

  • 11v input
  • 5v logic
  • H-bridge included
  • 0.15A output current

Reason for specified IC

  • SMD available
  • Break out board sold from sparkfun for testing
  • Available on DigiKey

Link to requirements

  • L1-2 Motion
    • The prosthetic hand shall have individual motion in at least 2 fingers
  • L2-3 Motors
    • The hand should flex and extend using motors.

Arduino Micro

Purpose

  • Receive and send data from the xbee
  • Read Analog voltages from the force resistors
  • Control the motor drivers based on inputs from the xbee
  • Control the servo based on inputs from the xbee

Reason for specified MCU

  • Serial Communication
  • 6 Analog Pins
  • 6 Digital Pins
  • 4 PWM Pins
  • 1 Timer
  • 5v logic, but also accepts 3.3v logic
    • Useful because xbee is a 3.3v device
  • Available from last semester

Hardware Design

by Manufacturing and Design Engineer | David Mendoza

Link to Final Prosthetic Hand Palm Design Blog Post:

Prosthetic Hand Palm Design

Link to Final Prosthetic Hand Fingers Design Blog Post:

Prosthetic Hand Fingers Design

Verification Tests

by Mission, Systems, and Test Engineer | Chris Bautista

Link to Verification & Validation Report – Prosthetic Hand:

V&V Prosthetic Hand

System Resource Reports

by Mission, Systems, and Test Engineer | Chris Bautista

Power Allocation

Mass Allocation

Cost Allocation

Burndown

by Project Manager | Bianca Esquivel

Project Resources

Project Video: Prosthetic Limb 2017 Project Video

CDR PowerPoint: Prosthetic Hand CDR PPT

PDR PowerPoint: Prosthetic Hand PDR PPT

Project Libre & Excel Burndown: Prosthetic Limb Schedule & Burndown

Verification & Validation Report: V&V Prosthetic Hand

Solidworks Files: Mechanical Blog Post 1, Mechanical Blog Post 2

Fritzing Files: Electrical Blog Post 1, Electrical Blog Post 2, Electrical Blog Post 3

Eagle CAD Files: Electrical Blog Post 4

Arduino Code: Software Blog Post

Bill of Materials: Prosthetic Hand Reimbursement Form

The Entire 400D Prosthetic Limb Folder: Prosthetic Limb 2017 Group Folder