THC Project

Keypad – work in progress, part 2 – 20/1/09

I’ve started doing the wood work,

Now that I have all the electronics I need for the keypad, and I have a fairly good concept of what I need to do after a test drilling I went on and started building the operational thing.

first I had to make the keys themselfs. I took the Laptop keys written on and covered with laquce (see previews post on the subject), and glued it to the pushbuttons I’ve bought.

Next was to construct a wooden box, I’ve choped off some old furnichers I found on the street, and drilled holes for the PBs.

Keypad - Before drillingKeypad - Post Drill

The box – before and after drilling

After this is done, I’ve mounted everything to make sure it fits. and off it does into paint.

Keypad – Before going into Paint
THC Project

Build update – 17/1/09

The I-PAC and Joystick arrived this week, so I was able to start testing the correct way to get everything working the way I wanted.

The stick connected to the controller During trials
The stick connected to the controller During trials

I’ve hooked up the joystick to IPAC and started working on it. 2D control (UPDOWN and LEFTRIGHT translations) have been tested. I’ve also tested the keypad. Unfortunately the IPAC has some limitations I was not aware of.

  1. It only supports one keystroke per PB.
  2. it support key combinations only via a “Macro” command (only 4 macro commands are available)
  3. when a PB (PushButton) assigned to a macro is presses the macro is issued only ONCE.

After consulting with Andy from ultimarc (creator of the IPAC) We have come to a conclusion that the correct way of doing multiple key strokes will be to program a Macro that will be triggered along with a keystroke . that means that each PB will be connected to both a unique keystroke and a “common macro”. this generates another problem, because all the PBs will share a common ground and the “common macro” once one of the PBs will be pressed they will ALL trigger. Again, Andy has given me all the answers I needed, and the circuitry would include 1N4148 diodes connected on each of the “common macro” “legs” to prevent this from happening.

Keypad Test Drill
Keypad Test Drill

I have also made a test drilling of the Keypad panel, This was done in order to evaluate the accuracy of my “blueprint” and to make sure I know what are the correct drill sizes I need.

THC Project

Build has started – Keypad, Part 1

I’ve finally went and bought all the switches I need for the keypad.

I’ve got 32 Pushbottons, 1 toggle switch and IDE “Bath”. (I actually got spares for everything due to the lack of sodering skills). all for about 25$

I’ve also “salvaged” 34 Laptop keys (32+2 spares) for gluing on top if the pushbuttons. I’ve got cheaper type of pushbuttons to cut down costs (and not the square type I was thinking to buy).

I’ve wrote the text directly onto the plasic and sprayed with a coat of Lacquer for protection. my hand writing is well, bad – but I found no Other way to get white text within the key size (1.8 cm).

Keys drying after Lacquer coating
Keys drying after Lacquer coating
Keypad drwing
Keypad drwing
THC Project

THC Project Expands.. :)

SSM2007 Keypad
SSM2007 Keypad

The I-Pac VE controller chosen for the Project – supports 28 switches, the THC itseft will use only 6 of them.

So I will try and add a keypad and hopefuly it will be functional later on down the road – on current SSM version (2.4) it will not be functional.

I’m pretty sure I will use the Apem 1415N switches – they pretty much what I need (and only a tad smaller then the real thing). but that might change during the build (havn’t ordered them yet).

I will try and use an IDE connector – but I am currently unable to find a decent IDE socket. I’ll need to start scavange Mobos to see if I can dissmental two.

if this will not wok, I will use an IDE cable (without the connectors) – this will allow me to hook up all 33 planed switches (from the keypad side) for future possiable upgrade.

shuttle Keypad is 8*4 – which makes it 32 switches . In addidtion I plan of using the controller “Shift” functions to allow me to use a simple off-on toggle switch and use the same keypad as two of the shuttle keypads (future upgrade will also allow On-Off-On switch to simulate 3 keypads by running two seperate shift modes).

A short count shows that the current controller only allows 22 more switches to be connected (6 are THC). luckly for us SSM only uses 21 of the keypad’s 32 keys. 0-9,period (.), + and -,OPS, ITEM, EXEC, SPEC, PRO, CLEAR, RESUME and GPC/CRT. one is of course the toggle switch.

THC Project

Off we go!

This Blog/site will follow my THC project.

THC at work during STS-57
THC at work during STS-57

The project was born from the desire to have as much fun as possiable out of Space Shuttle Mission 2007. But hopefully it will also usful for every space sim around.

First some background.

The basic concept is simple and striaght forward. to make a functional and affordable Transitional Hand Controller.

A few important requirements that must be met were made – and they Guide the design.

  1. Due to current application limitations (as of Dec 2008) – the THC must transmit key presses.
  2. The THC must be programmable. For compensation for changing keyboard layout, and to enable support for other games as well.
  3. USB or PS2 interface – with preference to USB for future support (“Built to last”)
  4. Make it as simple as possible – for an electronic noob like me, it’s a must.
  5. 3 axis control at the same time
  6. functionality as close to the Real deal as possible
  7. Ability to Expand, customize and upgrade – simple as possible.

The Design

I’m going for a simple concept, use shelf products (with adaptations) in custom housing. The Design is greatly based on work done by Arcade fans in the MAME project. thanks to them a lot of hardware is available. for example:

For the “Push/pull” axis I will try and mount the stick on four guide rails using the holes for the screws, I will then “lock” it into place with springs to allow about 1.25 Inch (3CM) of

movement. this will cause a microswitch to close triggering the FWD/AFT translation command. but it will probably change a bit when I’ll see the stick.


the I-Pac2 controller I’ve chosen allows 28 buttons (one of them can be a “shift” button). and the THC functions only require 6 of them (four ways+push/pull). that leaves me with 22 unused commands. those would be useful for a keypad.

I will probably add in and external connector to allow easy hooking up of add ons (such as the keypad) – the connector will probably be an LPT port (25 pin serial) or an IDE connector (40 pin interface). the LPT is simpler to obtain while the IDE will allow further upgrade via the I-PAC4 controller, allowing a full shuttle keypad (32 keys + a shift toggle). on IPAC2 the keypad will be more limited and will only have 21 keys (and one shift toggle).

more on that as the project moves ahead.