Human Centrifuge – The Two Player Game!

Project Description

In the lastest 72 hour competition, My friends and I decided to go BIG! We were inspired by NASA and it’s G-force machines, to create a game version, we called The Centrifury. In a single night, we ran to the chalkboard in my home, and sketched the idea, the problems, and created solutions.

Idea: A double dead-man switch operated game of chicken and g-forces, two opponents would enter the ride, buckle up, and hold down their respective buttons to begin the game. The game begins by slowly accelerating the players around a tight axis, eventually reaching 5Gs (commonly found on the world’s fastest roller coasters). Whomever let go of their button first, would end the game, and the winner’s game panel would light up letting everyone know who won.

Problems: Power and data from the top to the bottom. The top is going to have buttons, LEDs, and power, but will be spinning at an alarming speed. In the short 72 hours we have, we could not source decent slip rings to carry the power and data from the base to the top.

Solutions: I suggested we use two XBEE radios, a separate power source on the top, and microcontrollers on both side to relay data back and forth. Any miscommunication in the wireless data flow would immediately end the game and commence braking of the motor controller on the base. I also set the encryption flags in the XBEE radios firmware, to prevent anyone from ‘hacking’ the protocol and overriding our game safeties. It would include an active message setting the state, if the message was wrong, or didn’t arrive for a second, the motor controller would brake and shut down. Finally, we included a large high power physical switch on the power, at a distance from the machine, to override any software bugs that might occur in initial testing – the safety factors were important.

Project Details

1 Golf Cart Motor and Axle
1 Victor 885 motor controller
2 Zigbee XBEE radios
2 Arduinos
10 Feet of Addressable LED Strings
3 SLA Batteries
2 Waterproof Project Boxes
80 Feet of 1/4″ Square Tubed Steel
16 Feet of 6″ Diameter 1/2″ Thick Steel Tubing
16 Feet of 5″ Diameter 1/2″ Thick Steel Tubing
4 Sheets of Marine Grade Baltic Birch Plywood
2 Upcycled Car Seats and Seatbelts
2 Sheets of Steel Mesh
1/2 Sheet 1/4″ Plexiglass
1 Broken Welder
2 Emergency Stop Buttons
2 $0.99 Pool Noodles

The CentriFury is constructed from tube and pipe steel. The chairs and seatbelts were recycled from the junkyard and reupholstered. Power came from an axle of a 4 person golf cart and two deep cycle 12v batteries, and one SLA bettery for the top. The wheel drives a plywood base to create the spinning action. We used a Victor 885 motor controller to control the motor. A wireless setup was used to connect the buttons to the motor using a Zigbee wireless pair and two arduinos controlling several relays as well. The buttons are secured in two etched acrylic signs. LEDs are used to light up the signs and display the winner. The signs were designed and cut on our homebuilt CNC machine. Two 99 cent pool noodles were used to complete the build.

After a successful build, we painted, and touched up many things, as this machine has been all around the country since! It has been featured on Discovery Channel, Science Channel, Red Bull, Makezine, Popular Science, Popular Mechanics, and many more! It was the biggest feature of the 2013 World Maker Faire in NYC, proven by our longest line that stretched across the field, only the Gyro guy had a line that rivaled ours! I learned what it was like to run a carnival ride, extremely satisfying!