Ben Cazzolato

Chris Dyer

Kane Fulton

Jonathon Harvey

Evan Schumann

Charles Zhu

Luke Charles Francou

Jack Scott Parsons

Benjamin John Wright

Bo Zhu

Jonathon R. Atterton

Ben L. Davis

Samuel C. Hart

Erin E. Pearce

EDWARD - Electric Diwheel With Active Rotation Damping

Ben S. Cazzolato, Chris Dyer, Kane Fulton, Jonathon Harvey, Evan Schumann, Charles Zhu, Luke Charles Francou, Jack Scott Parsons, Benjamin John Wright, Bo Zhu, Jonathon R. Atterton, Ben L. Davis, Samuel C. Hart and Erin E. Pearce

Introduction

The Star Wars movies have had numerous exotic vehicles including the Monowheel (or Wheelbike as called in the movie) and Diwheel (Hailfire Droid) as seen in the images below.

A simple introduction to monowheels and diwheels may be found on Wikipedia.

For more information on monowheels see The Museum of RetroTechnology, which also has information on diwheels. In particular THE DAVID SOUTHALL MONOWHEEL is worth a look at, especially the movies. Kerry Mclean has some very cool monocycles. A more refined monowheel is The Brazilian "Wheelsurf" Monowheel.

The EDWARD Project

This honours project involved the construction of a human operated diwheel. Many diwheels in the past have been human powered or powered by IC engines. This one is purely electric. It has additional functionality lacking in other models, including inbuilt dynamic lateral stability and slosh control to prevent "gerbiling" or tumbling in aggressive braking or acceleration maneuvers. The diwheel also incorporates a unique feature that allows the rider to drive the vehicle when "upside down" - keeping the vehicle in its unstable state is achieved using a combined swingup and inversion controller. The mechanical design and some of the electronics was completed in 2009, with the majority of the electronics and control systems developed in 2010. A photograph of the final system is shown below.

YouTube video highlighting the outcomes from 2010

The following links also feature EDWARD:
MechExpo 2010
MechExpo 2010
MechExpo 2009 - Totally Wild TV
MechExpo 2009 - Ten News
7 News Adelaide, Sat 21st May 2011

FAQs

• Top Speed - ~40km/hr. This is limited by the drive ratio of the motor and drive wheels. It is possible to change this ratio to increase the maximum speed, but this would be at the expense of the rapid acceleration and maneuverability.
• Maximum Incline - ~12 degrees. This is simply a function of the mass of the wheels and inner frame, and their mass distribution. It should be noted that EDWARD was designed to have a high centre of gravity to make it susceptible to slosh and tumbling. This high c. of g. has limited the maximum incline that can be climbed (without forward momentum) to a relatively gentle gradient.
• Braking Deceleration - ~0.2G. This is also a function of the mass of the wheels and inner frame, and their mass distribution. The high c. of g. in EDWARD has restricted the maximum acceleration/deceleration to be about 1/4 what a bike or car can achieve on a dry sealed road surface, and more like a lose unsealed road. Again, it is conceivable, using alloy wheels and frame, and intentionally keeping weight low, to realise a design with a deceleration of 0.7G, which is not much lower than most vehicles.
• Battery Life - ~1hr. We typically get about 1hr from the existing sealed lead acid batteries. This would involve a fairly aggressive driving style involving rapid turns and spins, tumbles and acceleration/deceleration. It is likely that a more sensible driving regime with slosh control on would provide several times more time before swapping the battery pack.