Fullmotion-Racing-Sim

This is a dream project of mine for a while. Until I can price out a spec sheet that is under $300, I won't start building any hardware.

Goals

• 5 axis

  • pitch
  • roll
  • heave
  • surge, sort of, simulated through tilting?
  • sway, same as above

• At least 45 degrees of motion

  • +/- 22.5 degrees, modeled by D series pickup in BeamNG

• Somewhat accurate bump simulation, very fast acceleration

  • roughly 3,800 m/s/s to simulate a 45 degree ramp (1 x 1 meter) at 100km/h
  • enough to feel back pain

• Compatibility across games

Inspiration:

https://www.xsimulator.net/community/threads/flypt-6dof-brushless-diy-actuators.10799/

• Problems
  • Too expensive for my taste
  • Motors cost $120 a piece, they need 6 of them
• Good
  • I like the design, it simplifies the design of moving in all of the axis
  • Easy calculations, all based on triangulation
• Better
  • Using the actuator layout, I think I can implment a pneumatic air system. As long as my HFT compressor can keep up with air demands, this shouldn't be an issue.
• Cost cuts
  • No point in yaw for driving, sway and surge can be simulated. This leaves me with only needing 3 actuators

https://www.simcraft.com/apex-pro-6dof-racing-simulator-chassis-motion-system-yaw-pitch-roll-sway-surge-heave-independent-full-motion-driver-development-full-service/

• ultimate goal

Ideas

• Use FPGA instead of microcontroller for processing, for lowest latency
• Serial port communication
• Race controls
  • Ebay ricer steering wheel and seat
  • Junkyard throttle body and accelerator pedal
  • Junkyard brake and clutch booster
  • Accurate feel H pattern shifter

Brain log

version 0.1

Electronics:

• usb to rs232
• Altera ep2c5t144C8 for triangulation calculations
• Pneumatic solenoids
• Custom driver board

Software:

• Figure out how to grab data from BeamNG, either by simulating a controller, or directly grabbing lua
• FPGA dev, find the equations for caluclating triangle based on the input data

Hardware:

• DIY 3" pipe as pneumatic cylinders

Calculations:

• lengths of actuators for a equalateral triangle seat base of 1m sides
  • tan(20) = ~14", I will make it 24"
  • 3" air cylinder diameter
• air compressor spec requirement
  • cylinder volume: 0.097801 cubic feet
  • total cylinder volume: .2934 cubic feet
  • harbor freight compressor: 4.5 CFM, derate by 75% to 3.375 CFM
  • equates to 11.5 full inflates per minute (moving from bottom to top)
  • if this becomes a problem I'll pickup this bad boy and a shitty toyota engine

version 0.2

Electronics:

• RS-232
• Altera ep2c5t144C8 for triangulation calculations
• Custom driver board

Software:

• C# implementation of sending BeamNG MotionSim data to a serial port, with a UI to control the strength etc.
• FPGA dev, find the equations for caluclating triangle based on the input data

Hardware:

• dumping the air compressor idea because of the major lack of portability.
• HFT corded drills attached to a rack and pinion system, or belt drive.

Calculations:

• lengths of actuators for a equalateral triangle seat base of 1m sides
  • tan(20) = ~14", I will make it 24"
  • 3" air cylinder diameter