[6.20.10] KillerCycle: Excersize Bike Game Controller


Excersize Bike PC Game Controller with snazz

How Much
Components How To Results (VIDEO) IMAGE DIRECTORY

COST? Image/ Media
Cheap, if you can scavenge the parts. The heart of this, er.. creation, is a 1980's sears exercise cycle.  If there isnt one sitting in your grandparents attic or a neighbor's garage, try hunting the craigslist. Other parts of interest:
USB keyboard:
~10$ (free if you have an extra one :)
Microcontroller & misc. components (buttons, AVR, caps, 2n3904's, led's)
~$7 worth of components

What Do I Need  Image/ MediaImage / Media
Excersize bike:
Ancient bike, which inhabited our garage for the last decade. Make sure the mechanics are mostly working, or fix them before starting.
A rowing machine would also work great for this project, assuming you could find one for cheap. In the case for the rowing machine, a method to average the spinny part would be needed (RC integrator)

Microcontroller & old USB Keyboard innards (explained later on). Also some Debug stuff

<this project was designed to get a 12 year old interested in tinkering, so most parts are kept simple>
Computer that can play ancient games / emulate older consoles

Good, strong momentary pushbuttons (mouser link)

A note, if your going to build this, dont, for any reason use the wimpy 4pack buttons from radioshack, they may be tempting, but they fall apart in hours. Big buttons that can take rough-housing are great. If your scrounging for em, try cutting out buttons from those giant TV remotes

DC motor
 (you could also hall effect sensor & magnet)
used for measuring wheelspeed.

How to:   Image/ MediaImage / Media
Start by taking off non-essentials (buzzer bell timer thing, ancient speedometers), and repairing any 'wobble' inherent to the vehicle.

Brace any less than functional parts and start laying out where buttons / feedback sensors should go

Start making button mounts.
 In this case, copper sheet was used, and bolted around the frame. The placement of the buttons were based on a younger siblings hand size. also, hone down any sharp edges. Four buttons were used (as this was designed around the game 'lego racers'. a Left, Right, Shoot and Swerve.
Forward is driven by the wheel speed & microcontroller (Discussed later)

Wheel Feedback
I didnt have any hall efect sensors floating around,  so we opted for a simple motor/generator approach. The bike had a 'speedometer' of sorts that was cable driven. After sanding and shaping the motor (from some toy), it was mounted to the geared wheelspeed apparattus. RPM translated into a voltage produced by the DC motor, readable by microcontroller's onboard ADC.

Keyboard Pinout- ing

The first revision of the system didnt actually use a usb keyboard,

Wait an hour, add water to the mixture regularly, it should be nearly boiling for the whole time.

As a rule of thumb, (longer in the mix = darker, shorter = lighter),

Keep in mind, the substrate started as pale / dark brown, lighter colored dyes (pink / whatnot) will come out odd.  I left mine in for an hour and 39 minutes,
(i lost track of time doing a hw assignment)

Before / After  Before After
First off, the board i used was over-etched.  The Dying was a test, to determine if the fiberglass pcb would absorb Dark Green RIT Dye,


UPDATE [4.5.10] Crimson PCB Dyeing
Process Before
Using the same dyeing procedures, another pcb that was left over (over etched / under exposed) was dyed crimson red. total cost <2$, time = less than 2 hours.

More info about the Crimson Dye used 

More Crimson PCB

(There's other photos in the photo gallery)
Concluding Remarks:

I was actually suprised how well this worked. If i did this again, i wouldve just found a wireless keyboard, instead of wired, and run the bike on rechargeable AA's / generator.

(be careful, im not responsible for your exploded computer, or newly chisled legs)

Rensselaer Polytechnic Institute 
Electrical & Electrical Power