Variable Speed Treadmill for Studying Neonatal Rats

From Mindworks
Jump to: navigation, search
Old rat treadmill.PNG
Sponsors Idaho State University
Team Name Rat Pack
Duration Fall 2018 - Spring 2019
Faculty Adviser Dev Shrestha
Mentor Jacob Miller
  • Michele Brumley/ Idaho State University
  • Nathen Schiele/ University of Idaho
Team Members
  • Colin Burkhalter, ME
  • Mitchell Williams, ME
  • Stephen Schoonen, BE
  • Stuart Sater, BE

The goal of the project is to design, build, and evaluate a variable speed and variable incline treadmill for exploring the impact of locomotor activity on the development of motor control and musculoskeletal tissues.

Problem Definition[edit]


Our treadmill will make research much easier for the lab technicians at ISU. Our robust and simple to control design will allow for less downtime and headache when testing the effects that early locomotion have on the animal's tissues. This advancement could help the researchers expand our knowledge of biological tissues and their formation/growth, as well as psychological changes in animal models.


The client has listed the project requirements in order of priority. It is anticipated that all of the following requirements will be met.

HIGHER Priority

  • Belt size: ~12 cm width x 20 cm length
  • Belt material that could be wiped off and cleaned, will not tear easily, and possibly be replaceable
  • Variable speed control ranging from 0.5 cm/s to 15 cm/s
  • User friendly interface for speed control – preferably developed in an open-source software program or via microprocessor
  • Treadmill will be operated in temperatures from 25 to 35 degrees Celsius
  • Removable transparent walls and bumpers

MEDIUM Priority

  • Variable ramp/incline angle from 0 to 15 degrees.

LOWER Priority

  • Automatic timer
  • Safety features including emergency stop button
  • Transparent belt and housing for video gait analysis (video camera mounted below the belt)
specifications matrix

Progress Tracking[edit]

Ratpack schedule.png


Ratpack budget.PNG

Design Considerations[edit]

Incline Mechanism

Ratpack Automatedassembly.gif
Ratpack Manual assembly.gif

Automatic Incline

  • Precise angle adjustment
  • Can be adjusted remotely
  • Provides active feedback through software
  • Allows surplus in lifting power for future design changes

  • Expensive linear actuator $140
  • Added complexity

Manual Incline

  • Requires no user electronic interaction
  • Quicker response time
  • Simpler

  • Difficult to adjust in incubator
  • Less precise
  • May require tools to operate

Motor Type

Ratpack DC.png
Ratpack stepper.png

DC Motor

  • Less noise and shaking
  • With encoder it can be easily controlled
  • Smoother, continuous motion
  • Lower torque
  • May require more coding to maintain steady speed
  • Difficult to monitor speed without encoder

Stepper Motor

  • Precise speed/position control
  • Relatively simple to program
  • Maintains constant speed with varying load

  • Noisy
  • 'Choppy' motion at lower speeds
  • High vibrations at low speeds

Control Interface

Ratpack touchscreen.png
Ratpack buttons.png

Touch Screen

  • Highly customizable
  • Easy to clean
  • Easy to understand
  • Sleek

  • Expensive, $50-$70
  • Relatively small screen/text
  • Potential for mis-selections


  • Simple to operate
  • Robust, solid controls
  • Low cost, ~$20 for all components

  • Potential for loose wires
  • More difficult to clean
  • Not as sleek

Project Learning[edit]

Lab Tour
Tour of Dr. Martins Lab to learn more about motor types and linear actuators. See full tour report here File:Ratpack martin lab tour.pdf

Linear actuator used in a pump
Stepper motor used in a pump

Control Interface
Research of different options for control interfaces. See control interface report here File:Ratrack userinterface.pdf

Example of a touchscreen interface

Final Design[edit]

Rat pack Main Assembly.PNG
Angled Up.PNG
Ratpack dissassempled design.PNG


Team Members[edit]

Ratpack colin.PNG
Colin Burkhalter

Major: Mechanical Engineering
Graduation Date:
Future Goals:

Ratpack stu.jpg
Stuart Sater

Major: Biological Engineering
Hometown: Sandpoint, ID
Graduation Date: 12/15/19
Future Goals: Become an expert on the effects of spaceflight on vision

Ratpack stephen.PNG
Stephen Schoonen

Major: Biological Engineering
Hometown: Idaho Falls, ID
Graduation Date: 12/15/19
Future Goals:Futhar my educatoon by attending medical school

Ratpack mitch.jpg
Mitchell Williams

Major: Mechanical Engineering
Hometown: Coeur d'Alene, ID
Graduation Date:
Future Goals:Secure a job in the manufacturing Engineering field

Additional Documentation[edit]

Meeting Minutes

File:Ratpack minutes all.pdf


File:Ratpack design review presentation.pdf

Client Interview

File:Ratpack client interview.pdf