Gemini Enthusiast
Howdy! Recently joined the forum, and have been busy over the last six months or so building a Gemini capsule simulator. Used to play as a kid with my brothers in a closet with an old oscilloscope and switches, etc. and pretend "space food" that we were astronauts launching on various missions. Last year saw two of my daughters doing something similar with a large cardboard box with "controls" taped and colored onto it. Suddenly realized that I was a control systems engineer, and could do something really cool like that!
So half my garage has been taken over for a full-sized Gemini capsule simulator mockup. Mercury sounded boring (just along for the ride, and no company) while an Apollo capsule was too large for both my garage and too wide to trailer to other sites. Gemini was "just right"! Also, it was the program running when I was born and is pretty much at its 50th anniversary.
So far I've got half the capsule structure finished, a framework for the control panels welded together, and have completely wired built and wired the command pilot and pilot breaker panels (including the wire guards and the special arming switches). I've also custom made a number of the gauges using servo motors, such as descent gauge, acceleration, and propellant quantity. Used an old aircraft altimeter hacked apart with a stepper motor for that instrument. Have finally figured out a design for the "8-ball" and am working on that. Have even built a "water gun", using the pressure diaphragm from an RV water supply to provide the "tank". Been playing around with a vacuum sealer to make the "menu" items as consumed during the various Gemini missions. It won't be 100% accurate - for instance I compromised and bought a couple of race car seats and harnesses rather than try to make my own. But it should be pretty fun when done! the entire thing is designed to be tipped back to simulate "acceleration" during launch (I've got a 3" pneumatic piston and garage door springs for the actuator). There are two vibration transducers mounted to the seat backs as well as a 100 watt subwoofer for the sound effects. Using a cheap motorcycle comm system for the radio and intercom effects. All of the switches will be wired to the "computer" which I've built from 9 Arduinos and an mp3 sound board, all talking together with I2C (TWI). I even custom carved a joystick to match the one found in the Gemini, complete with twist grip for yaw control and two buttons for the push-to-talk switches. Also purchased a short-throw DLP projector for simulating the view outside the viewports.
Honestly the only part I'm still not sure how to do is retrieving/sending values with the Orbiter software. I've never written a DLL, I'm familiar with machine language programming, and have done Basic, , VB, C++, Fortran and Pascal programming. But I've never done anything involving the windows environment like writing a DLL. So I'm a little intimidated by that step, but hopeful I can figure it out when the time comes. I can do keyboard emulation with an Arduino Leonardo, as well as the joystick emulation so that isn't the problem. My main concern is being able to send data back to my simulator such as attitude info, altitude, etc. for display on the instruments. I could use a com port serial stream (which I'm most familiar with), or possibly something with an Ethernet shield (which I haven't used before). If anyone has any good pointers for me I'd love to hear them! Most useful would be if someone has built an interface like this before, which I could use as a starting point. I've seen lots of discussion in the forums about this kind of thing, but no concrete information from someone who's done it.
Anyway, looking forward to getting this project done - will be taking it over to the school next door to play with as part of their science program. But don't expect it will be done until later next year! So far I've spent around $3K on it, not too bad really. A couple of construction photos attached. Cheers!