Taranis Single Stick Build

[rockyboy]

Like a few dozen other people I've been eagerly awaiting a Single Stick transmitter based on the excellent FrSky Taranis radio platform. Wayne over at Aloft Hobbies teased the world with a prototype back in Feb 2015 and it was love at first sight for me:



But that was a long time ago. And in the meantime a few crazy people have built their own amazing looking custom versions


And I really really want one, but with FrSky focusing on the Horus, I just don't think they will get this up on their priority list anytime soon.

So it's time to go a little Mad and see if I can building something to be proud of.

Step one: Acquire used Taranis, aluminum project box, 3 axis hall effect gimbal, and a couple slider pots.



Step two: Get very cool control knob from eBay that looks great, but is threaded too big for the stick at the moment. Need to fix that eventually.



Step three: start modifying Wayne's control layout to better match the switches I use frequently.



Next up: get out the paper, pencils, calipers, etc. and build a foam box to test fit the parts.


The Mad Scratch Building Corner seems like the most appropriate place to put this at the moment. Moderators - if there is a better one please do fix me up here.

 

[JohnRambozo]

Awesome idea. It looks great. My only concern is the throttle placement for race quads. It seems like that would be really hard to manage your throttle as much as you need to for a quad with it on the side like that.

 

[Craftydan]

The Mad Scratch Building Corner seems like the most appropriate place to put this at the moment. Moderators - if there is a better one please do fix me up here.

You are scratch building this together and have shown a sufficient lack of sanity to take on this build. Rock On

Two things I'm wondering about: Trims and ergonomics.

For trims, I've always let the left hand drift to the correct trim switch (set the throttle and the left hand is usually free to work) and on a traditional radio the layout sensibly fits the trim next to the axis it trims . . . but not really an option on a single-stick. since the left hand grips the controller with fingers free to work, what about recessed trims on the back inside grip for the left hand? maybe a cover?

As for ergonomics . . . how do you plan to hold the radio? grip in the left hand? tray? The right hand is pretty much locked on the stick anytime you have to actively control the airplane, so unlike others where you can thumb the stick and flip switches and sliders with a finger, it seems to me the auxiliary controls on the right will be . . . complicated to use.

in any case, looking forward to seeing this progress

 

[rockyboy]

Awesome idea. It looks great. My only concern is the throttle placement for race quads. It seems like that would be really hard to manage your throttle as much as you need to for a quad with it on the side like that.

Yeah, I agree. Not sure this will be the right platform for multi rotors - almost certainly not good for racing or multi-rotor acrobatics. Probably.

But I think it's going to be really neat for fixed wing - cross wind landings or other conditions where rudder movements blended in with the other controls are very important.

 

[rockyboy]

You are scratch building this together and have shown a sufficient lack of sanity to take on this build. Rock On

Two things I'm wondering about: Trims and ergonomics.

For trims, I've always let the left hand drift to the correct trim switch (set the throttle and the left hand is usually free to work) and on a traditional radio the layout sensibly fits the trim next to the axis it trims . . . but not really an option on a single-stick. since the left hand grips the controller with fingers free to work, what about recessed trims on the back inside grip for the left hand? maybe a cover?

As for ergonomics . . . how do you plan to hold the radio? grip in the left hand? tray? The right hand is pretty much locked on the stick anytime you have to actively control the airplane, so unlike others where you can thumb the stick and flip switches and sliders with a finger, it seems to me the auxiliary controls on the right will be . . . complicated to use.

in any case, looking forward to seeing this progress

Thanks!

The trims are bugging me too - I've ordered a little track pad like four position switch (think old Nintendo controller parts) to see if I can experiment and get all of the trims to be accessible by the left hand in one tight cluster. I like the recessed back idea, or perhaps further down the case by where I was going to put the power cord. No reason the trims need to be near the sticks after all.

For ergonomics, I'm hoping that the old school left arm cradle will feel comfortable getting to the switches, and than I can adjust my radio programming so basically every switch I use in flight will be accessible by left hand on the side/top of radio, or by right hand pinky finger. The other switches and pots on the front of the radio would be used for 'non-flight' types of controls - i.e. throttle cuts and mode shifts that are too drastic for in flight use.

The backup plan is to build it tray style and look a little more like a sound mixing board with throttle and other slider pots on the left side of the radio.

 

[rockyboy]

Step 2: The Prototype

Pulled apart the donor radio and started on the foam prototype.



Taking lots of pictures of the Taranis wiring for future debugging.





I plan to make a printable CAD drilling template along the way too - just in case anyone else is crazy enough to try this in the future.

 

[rockyboy]

Step 2.1 Prototype Continued

More progress on the prototype - using printed CAD drawings as the templates now - more pieces installed. After experimenting a bit, I'm moving several switches for easier access, which is exactly what I wanted to learn from the prototype.

Next steps include drawing up a detailed wiring diagram, test fitting the rest of the switches and the back plate, and preparing the CAD drawings for laser cutting.

 

[rockyboy]

Wiring notes and CAD file expanded. Will probably do one more foam prototype using the updated template before moving on to a wooden laser cut box. Then on to the aluminum case after some flight testing!

 

[rockyboy]

More work on the foam prototype tonight, a first sketching of the back surface, getting all the switches installed, and some of them moved around a bit. In a few cases, just a 1/4" difference in placement means I can reuse the existing wiring harness. In most cases, the movement is purely for ergonomics.

Time to print out and build a new foam template - it's getting hard to read my notes on this one.

 

[rockyboy]

Prototype 4 - we've got wood!

First assembly into the wooden case tonight. A couple minor tweaks to the CAD file identified, but largely it went in as expected.

Next steps:

- Build mounting brackets for linear pots
- 3D print buttons for main control panel and new 5 way tactile trim switch
- Electronics modifications to get the new pots and gimbal into the wiring harness
- Extend the switch leads that are too short in the new layout
- Solder IPX antenna jack to back board

 

[rockyboy]

Progress this weekend, but no pictures. Printed up the speaker holder - glued it in, soldered it up. Connected a new power jack that fits in a round hole instead of the weird mailbox shaped hole the stock one needs. Built a mounting plate for the throttle pot and wired it in. 3d printed 6 new control buttons and sanded them to just the right height for the front tactile switches. Fabricated a leather hinge for the back of the box so it will lay open when I want it to, but stay together enough not to yank on the wires.

Next steps are fabbing a control button for the 5 way trim switch and wiring in all the trims, making extensions for the switch cables that need to connect to the back plate, wiring in the main gimbal, soldering the tiny antenna IPX connector on the back board, and adding the battery strap.

Then comes the magic smoke test.

 

[rockyboy]

Progress and pictures this time

I hollowed out a little piece of dowel to make a control knob for the 5-way trim switch after a couple frustrating 3d printed ones just wouldn't fit right. Seems my 4 year old kickstarter edition PrintrBot is just not precise enough to do what I need for this part. So you know what that means - a new 3D printer build is now on the project list

Extensions for all the switches are done, and that tiny little IPX connector is soldered onto the back board. That piece went much easier than I was expecting, and after the first try everything tests out OK with the multi-meter. I'll probably do this mod to my main Taranis too.



Could use a little better cable management in there too.



I have stronger springs on order - that fat aluminum knob is just too much for the stock ones to hold up.



Looks pretty nice up front - even if I did forget to put in a speaker grill before gluing everything in place behind it. Oh well - I'm sure it can be pulled out and fixed.


Next steps:
- Add speaker grill
- Wire in the gimbal
- Wire in the trims - scratching my head a little bit over the pinouts on the 5 way switch and the best way to match them up. Need to do some experimenting, but I think it's setup to accept either a common ground with power coming into the switch contacts, or a common power with grounding happening on each switch contact. Not sure why else it would have both power and ground pads along with dedicated pads for each switch sensor direction.
- Add the battery strap. Leaving this for last as it's just going to be in the way of the soldering work.

 

[PsyBorg]

and just how many aircraft do you expect to be controlling with all them knobs n buttons n switches? There are less switches on my 32 channel 8 buss mixing board. That might even rival the effects rack for fiddly things.

Nice work on that. It even has that Steam punk look starting. BTW I love the little etchings of your logo and the plane chasing the pilot hehe. Nice touch.

 

[rotozuk]

Nice job.

We completely changed our layout based on feedback and a few placement issues we wanted to improve on. We now have most of the trims on the side, and our single stick has a button on it for use with autotrim for those that like that function.

We hit a roadblock on our production version of this radio, but we have a fix, just need to tweak our cad and do some more testing. Our goal is to have very few screws coming in from outside the case. You will notice our prototype had very few exposed screws.. I know, not a big deal to many..

Looking forward to seeing your progress!! Keep up the good work!

-Wayne

 

[rockyboy]

and just how many aircraft do you expect to be controlling with all them knobs n buttons n switches?

All of them of course.

Nice work on that. It even has that Steam punk look starting. BTW I love the little etchings of your logo and the plane chasing the pilot hehe. Nice touch.

Thanks alot - now that you've put that thought in my head, I want to start switching all the black plastic screw heads for brass ones....

 

[rockyboy]

Nice job.

We completely changed our layout based on feedback and a few placement issues we wanted to improve on. We now have most of the trims on the side, and our single stick has a button on it for use with autotrim for those that like that function.

We hit a roadblock on our production version of this radio, but we have a fix, just need to tweak our cad and do some more testing. Our goal is to have very few screws coming in from outside the case. You will notice our prototype had very few exposed screws.. I know, not a big deal to many..

Looking forward to seeing your progress!! Keep up the good work!

-Wayne

Thanks for the update Wayne, and I appreciate the kind words!

On the production challenge, I believe visible screws should be at one extreme or the other - lots of them as a design feature, or all hidden away. I think the key is doing it with intention - not just whatever happened based on the parts that arrived.

And I can see that button on the stick being used for bomb drops too.

Looking forward to seeing your next prototype/finished version!

Thanks!

 

[rockyboy]

Finally got back into the shop and spent some time getting this closer to complete last night. All wiring is complete except the elevator/aileron/trims connector block.

I really like how the 5 way tactile trim switch is working out - one nice compact control for both elevator and aileron trims. I didn't hook up the center push button contacts yet, but might think of something to do with that one in the future. I got mine off fleabay, but it's basically this unit for the curious https://www.sparkfun.com/products/retired/11187



Should be ready to power it up and see if the magic smoke comes out this weekend

 

[rockyboy]

Aargghh!! Turns out the really nice feeling CNC milled 3 axis controller from Flobby Fling only has two working axis. Lots of quality time spent with a multi-meter to confirm, but the hall effect sensor for the rotary 'rudder' movement is a dead sensor, locked at a single resistance of 39k across any combination of contacts regardless of proximity to the magnet. I switched it out for the elevator axis sensor to confirm that yes, it's a dead sensor board. And this is my 3rd dead electrical component from the king in 5 orders, and I haven't been able to get either of the first two (dead motor and dead flight controller) replaced through their miserable support.

So I just ordered both of the 3 axis stick kits from Aloft. I'm confident they will work (the advantages of a reputable dealer), but honestly I'm not as excited about the design of these options. I'll try fabricating a custom knob to get to the look and feel I want, but at least I'll have a working control to fly with.

 

[rockyboy]

It's Alive!!

Thanks to Wayne's fast shipping from Aloft :applause:, I received the last 3 axis gimbal kit he had in stock today.

Instructions for modifying a stock Taranis gimbal to use the new knob were very straightforward - only took about 15-20 minutes to have it all done. Swapped this assembly out for the broken Flobby Fling part, and we're in business!!



Behold, a fully functional single stick Taranis in a laser cut wooden case! Fired right up, and after switching a couple wires to get the stick movements going in the right direction it calibrated perfectly.



Every function of the original Taranis is working in this case except for the throttle trim switch. Since I don't have or anticipate any gassers in my fleet, I didn't see any need to find a place for that.



Here you can see all of my trim controls - just the one stock trim switch and the little wooden knob connected to the 5 way control. I might get a second 5 way control and put them side by side on the final build just so every trim function of the radio is available.



So now it's time to pick a couple guinea pigs for testing at the field - think I'll use my Das Mini-Guinea Pig actually, and probably my Das Little Stick too - very stable and forgiving planes with rudders - while I get used to the new controls.

Then once I'm happy with the control layout, it's time to make all the tweaks to the plans I identified during the wooden build phase and get working on the final powder coated aluminum case.

 

[snoopy n flames]

Taranis single stick, please,please,please.

Hi rockyboy, just joined this group so I could contact you. I really like your work and would like to get your C.A.D. info. Got a NIB ACCST and a Hobby King 3 axis stick. I wished that Wayne could get back to at least making a run of cases.
I have a small brake and soon as I get the dimensions I'll be off and running. Thanks for any information, stubborn S.S. guys still refuse to go two stick. (how many full sized aircraft do you see that need two sticks in the solo configuration?
Thanks, Mike