Deltaalphalima1

Compared to more than twice that for a used DACO sensor, or nearly 7X more for a new one, (or 20X more for an OTTO sensor if you want to go that way), it sounds quite reasonable to me...

That sounds very interesting, could you post a link? The original sensor was indeed supposed to run off +/-5V, but since it’s just a variable resistor a lower voltage is fine. Worst case I could easily add some sort of negative charge pump to do the -5, at $100 it would be worth the extra effort if I turned out it needed it.

Thanks for the support! In regards to a level shifter, you actually don't need to use anything; a 5V Arduino will not damage anything if used correctly. The reason is that the I2C protocol is all powered by the master device (the throttle itself in this case) and pulled up to 3.3V with pull-up resistors, all the slave device does is pull the lines low (connect to ground), so it being capable of a 5V output won’t damage anything directly as it never output 5V in normal operation. The problem is a normal Arduino would need its own external 5V power supply, which if not implemented correctly could damage the throttle. It would also mean more wires coming out of the throttle, which is what we are trying to avoid in the first place. I actually used a normal Arduino Uno running at 5V for my first experiments which worked fine, as long as you understand exactly what you‘re doing. I may have overstated the risks slightly in the Instructable but better safe than sorry when it comes to multi $100 hardware I think. The mouse sensors Sokol1_br suggested would work, they are basically identical to a trackpoint sensor, and I can get them for not much at Digi-key https://www.digikey.co.uk/products/en/potentiometers-variable-resistors/joystick-potentiometers/82?k=MicroJoystick But they are bigger than ideal to be easily fitted. I am mostly looking at this as something that could easily be fitted by someone who didn’t want to modify anything and just wanted to buy a drop in replacement type sensor, so size it quite important, but something to take a closer look at. The reason for not wanting a larger slew deflection is quite simple, the real throttle has no deflection at all. It’s all based on force, kind of like a mini F16 sidestick. The problem this gives us is that there is basically no clearance between the slew sensor and the coolie hat on the back of the throttle. Meaning even using something like an Xbox thumb stick doesn’t really work, as it just hits the coolie hat when it moves, which is a real shame because they aren’t exactly hard to get. https://uk.rs-online.com/web/p/joystick-switches/1239578/ (a little cheaper than the DACO) Note the RKJXL series are only momentary switches, not any sort of joystick. They are nice to use as normal hat switches though. Using a proper force stick is actually really nice, it’s nothing like the original sensor, really fine and precise control, it really is a dream to slew the TGP around (also make Mav’s SO MUCH BETTER). The problem with the original sensor is that it has such a weak spring and moves such a small amount it’s hardly any better than just using a hat switch, you can’t really get any values between fully on and off, nothing like the proper sensor. As you can probably tell I’ve been thinking about all this probably far too much over the last few weeks (good to have a project though eh?) Another forum member also bought the other Chinook grip off of eBay, and has got the sensor out of it. I’ve sent him an adapter board like the one I made for myself, so hopefully we should have some independent feedback soon on that :) I think the next step should be to try and get one of the Xbox-style ALPS analog sticks working and in some sort of proper 3d printed mount. That would be a good proof of concept to start selling a few of these. All this makes me wonder what Thrustmaster has planned for the F18 Hotas throttle, if they are ever actually making one.

So as promised I have created a post over on Instructables with some details on how to interface with the I2C protocol used in the Warthog throttle. It's not got any detailed instruction on how to use an Arduino to do this yet, it’s a bit complicated as it requires a 3.3V microcontroller and I don’t want anyone blowing up there throttle with a 5V one so I need to make it as foolproof as possible, but maybe in the future. https://www.instructables.com/id/Thrustmaster-Warthog-Slew-Sensor-I2C-Upgrade/ In other news I have been looking at some possibilities of using other -slight less expensive- sensors. Right now I’m having some limited success with the TrackPoint out of a Lenovo keyboard, which actually operates in an identical way to the sensor in the real A10. Just finding a source that actually sells these seems to be a little tricky. I have also been looking as best I can find any other better replacement sensor we could use, but there is nothing I can see that both the right size (<20mm OD) and at some sort or reasonable price point. Thrustmaster might have had a point with the original... Any ideas as always much apreciated. Cheers

Cheers for the support, I appreciate it As far as it being one of a kind goes, I will happily make everything freely available. If I can get a few people lined up, and some sort of good supply of sensors, I would love make and sell a few. Of course with a proper production PCB and so on. You are correct that any sensor could be used (Xbox style thumb stick for example) it's just a matter of fitting it inside the throttle body. Any 3D design wizards out there feel free to chip in :) I'll put together a detailed explanation over the next few days (I’m thinking maybe Instructables?) I don’t want it to get lost in this thread if it could be useful to more warthog owners.

I’d not seen that post before, thanks for that :) Originally I did have a complex op amp amplifier circuit, but the sensor actually has an extremely high sensitivity, the datasheet claims 95mV/V. Running on 3.3V excitation voltage gives me +/- 300mV full scale deflection, that’s easily enough for the 10bit ADC in the microcontroller to map the 8 bits the throttle needs to send to the pc. So I ditched the op amps in favour of simplicity. I got really luck in that respect I think.

Thrustmaster Warthog Slew Upgrade kits are now available to purchase from my website https://deltasimelectronics.com/ ----------------------------------------------------------- Hi guys first post around here so I thought I would make it a good one. So I’ve wanted to upgrade the slew sensor on my warthog throttle for ages, and on one of my eBay browsing sessions came across this beauty: It's the FLIR control grip from an RAF Chinook (I think MK6 upgrade?), complete with force sensing mini joystick (I have already removed it in the above picture) This part is made by a UK company called DACO scientific. It doesn’t have any movement but give an analog output voltage based on the amount of applied force (it's actually 2 half bridge load cells). I've not been able to find all that much information on the actual part used in the A10C throttle but I believe it's a similar concept. So, next job was to interface this thing with the warthog throttle. I've seen a couple of other posts about guys who have added Xbox style thumb sticks to the throttle, but they have always used another USB joystick controller to do it. I wanted to interface directly to the existing throttle controller. The sensor that comes with the warthog is an AS5013 made by AMS, with talks I2C, so it was a simple enough job to reverse engineer the protocol using the datasheet and oscilloscope and simulate that sensor using a microcontroller. I knocked something together using at ATTiny841 micro I had lying about. This circuit just plugs straight in to where the old sensor did in the right hand throttle, no soldering or modifications required. This thing can do everything I need to simulate an I2C slave device and interface with the new sensor. Next I designed an adapter the fit the sensor in the existing hole in the throttle, and got it 3d printed by Shapeways (excellent service, would highly recommend). And we are done!! New slew sensor fitted and working perfectly!!! OK, so it wasn’t quite as simple as that. There was a fair bit of headache getting the microcontroller to talk nicely to the warthog throttle, as well as understanding how it handles all the calibration and self check features built it, but we got there in the end, and I’m very happy with the result!! For anyone who is wondering, DACO do still sell this sensor, but I contacted them to check for pricing and it would be about as much as 2 complete HOTAS systems to buy the sensors in one off quantity. So you're probably best off looking for used units on eBay, there is one on eBay UK at the moment, search for "BOEING CHINOOK MK6 HELICOPTER AIRCRAFT WEAPONS CONTROL GRIP" If anyone wants any more technical info about the I2C protocol used, or code running on the microcontroller I’ll happily do a more in-depth write up, just let me know. A few more bonus pictures attached below too :) Cheers