question regarding f 14 spider detent (emergency wing sweep handle)

[Yogi8]

Gentlemen,

Looks like we’re all working on a similar project. Here’s my attempt at making the emergency wing sweep handle work. I hope this helps!
 

 

[Gareth Barry]

Hey Yogi8, your cad and engineering skills put me to shame!

At the moment i am still waiting on some parts, and having to clean up some of the parts from tge guy who does my printing for me - they arrived with a heck of a lot of flashing.

[Gareth Barry]

Hi all

So, finally, another update. I have got most of the parts, minus the wingsweep handle. I just wanted to make sure that everyting else works and fits before I print this, as well as do a final check for dimensions and intereference.

Anyways, in this image, you can see how the throttle 'stalks' are hinged to allow lateral movement for example at the mil-stops and at idle cut-off.

You can also see the pulley wheel around which a belt will transfer torque for the auto-throttles that I hope to implement. I initially put teeth on the these to perfectly accept a GT2 type belt, but the company that does my 3d printing just doesn't seem to be able to print such fine resolution. In fact some of the 3d printing quality hasn't been great if I'm honest, but this particular company is cheaper than most others.

 

Yogi 8, here are some pictures of the 4 degree notch system that I will be implementing. A spring loaded catch in the wing sweep handle will pop out and slot into these You can see that the slots at the first and last position a cut all the way through to allow the handle to be stowed, as per the operation in NATOPS.

[Gareth Barry]

And some pictures of most of the throttle assembled, minus the wing seep handle and servos, but I feel that I am getting there. Althought to be honest, I look again at my thrustmaster t16000m throttle, and it really is a good piece of kit for the price....oh well I must sacrifice it in my quest to build a half decent simpit of the G.O.A.T of jets

Many things need correcting, such as the walls of the chassis being a bit flimsy, so I will need to add some stiffeners in the structure. I plan to add all these features before I publish this. Another error is that the flap handle is somewhat too small. In any case, I really think that Yogi9s effort puts mine to shame!

 

 

[Gareth Barry]

Rustbelt, regarding the forcefeedback gimbal, I hear what you are saying in terms of it being a shame to not use the programing that Heatblur have done, but to to be honest, I simply cannot afford the forcefeedback systems that are on offer- I would love to get one, but even getting into VR is going to be somewhat hard for me to justify.

So I think I am going to go the route of a gimbal that increases spring tension with increasing indicated airspeed, as well as a motor with an offset weight for vibrations. Both a fairly simple to implement via DCS Bios.

[RustBelt]

Skip VR.  It's just a headache and eyestrain you pay extra for. 

[Gareth Barry]

Interesting, and i really appreciate that honest insight, because that was what i was worried about, ie spending all that money on not just the vr headset but also a GPU upgrade only to be disappointed. Maybe I'll borrow an Oculus from someone to get a taste for it and see. It would be a real shame to lose all the beautiful graphic fidelity that i currently enjoy in DCS.

[draconus]

7 hours ago, Gareth Barry said:

Maybe I'll borrow an Oculus from someone to get a taste for it and see.

By all means, do it if you can, but be warned some things cannot be unseen

[Gareth Barry]

Hi Draconus

Do you use VR and what is your experience of it? It seems to be quite fiddly from what I gather in temrs of settings etc and with no guarantee in terms of what to expect in terms of visual fidelity. I think in terms of graphics, I might be easy to please as my current specs are;

GTX1660ti

16GB 2700 Mhz DDR4 RAM

SSD drive (can't remember the speed).

I play on a 1080p screen and whilst the visuals don't match what I see other people can achieve with fancier hardware, it more than satisfies me, especially coming from IL2 1946.

[draconus]

11 hours ago, Gareth Barry said:

Do you use VR and what is your experience of it? It seems to be quite fiddly from what I gather in temrs of settings etc and with no guarantee in terms of what to expect in terms of visual fidelity. I think in terms of graphics, I might be easy to please as my current specs are...

I'll keep it short as it is OT here. I'm one of those VR players that will never go back to monitor even with less than desirable hardware/performance. It simply amazed me from the start. I can accept lower fidelity and lower fps to stay in this virtual world but people reactions may differ. Don't know your CPU but you'll find your card lacking the needed power. In terms of fiddling with settings it's as far as you want to go. You can try different tricks and settings all day or you can just install, click Low preset and play instead. Feel free to PM me if you want to continue the discussion.

[Gareth Barry]

OK so some more slight progress. I have decided to go with a stepper motor, driving a gt 2 belt via 16 toothed gear. The throttles 'stalks' have smooth round surfaces over which the gt2 belt will run in. The tension and friction on the belt must be balanced in order to give a good smooth but even feel when the stepper motor is not turning. However, when the the stepper motor turns, there must be enough frction on the belt in order to actually apply sufficient torque to the throttle levers. I experimented with this and it seems to work fairly well, and is a simple solution I think. A stepper motor would also save me from having to write a PID if using a normal DC motor. The problem with an RC servo is that it is has a 'centre' whereas I dont want that due to the necessary 'slip' on the belt on the stalk end. I hope that makes sense. These stepper motors have a whole bunch of tprque and are extremely cheap. 

 

[Gareth Barry]

And now I have some questions for people with dual throttles or perhaps someone with knowledge of how the actual tomcat throttles function can respond.

My question is, is there any mechanical linkage between the two throttles to keep them moving together? I know that there there is the assymentric thrust limiter, but the NATOPS seems to imply that this is only for ensuring that both cans are lit at more or less the same time. It just seems somewhat disconcerting to me, coming from my t16000m throttle, so thrust assymetry isn't something I have had to deal with. The wide apart engines+thrust assymetry seems like a recipe for disaster (Maverick notwithstanding). I thought about perhaps linking the two via a magnet or something, such that they can be pulled apart if needed but that they usually 'stick' together- dunno if that makes sense or whether I am over thinking this.

[RustBelt]

No linkage. No two engines operate perfectly the same (especially without a FADEC system) so there will always be a bit of split to keep the thrust balanced. 

[draconus]

...and the shape of double throttle handles makes it easy to align.

[Gareth Barry]

Thanks guys- that's I guess why i embarked on this project, ie to learn to fly the jet as close as possible to how it was IRL. i guess I mostly use full mil, min burner and full burner in combat, so the mil stops should help keep everything aligned. I guess it's just something one gets used to in multi-engined aircraft.

So made some more progress today - most of the electronics have arrived, just have to do my final meaurements of the wing seep handle and then print that. 

I made a start on the wiwng sweep cover, was quite happy with the way it turned out. I discovered something called a 'mercury tilt switch,' which seems absolutely perfect for the wing sweep cover, so I ordered one and will be trying it out. Still going to use a reed switch for the handle extension.

[Gareth Barry]

Here you can see how i basically manufactured it - I first laser cut and engraved the main section from 3 mm acrylic. I then made a set of form blocks to the same radius as the throttle chassis, then heated the acrylic with a heat gun and pressed it between the form blocks - a bit of spring back here was a good thing as the radius needs to be slightly more than that of the throttle chassis. You can see one half of the form block in the background of one of the pictures. Anyway, once that was done, I cut the flat section on the bandsaw and glued the two pieces together using MEK. works very well. Masked and then painted grey. There was a bit of overspray, but that will be easily cleaned up with some polishing.

If you look at the last photo, I think it's still sitting a bit high relative to the rest of the throttle chassis, what do you guys think? I think I need to trim the bottom curve a touch to make it sit lower. I haven't drilled the hole for the swivel yet, it's just held on with prestick. I finish it up tomorrow. In the meantime I am going to get the stepper motors in place.

[Yogi8]

Looks dope! How does it feel??

[Gareth Barry]

Hi Yogi

That's actually a good question- I made some mistakes on the chassis design; in particular, I didn't give enough wall thickness in places which has meant I needed to glue some reinforcements to stop the walls from bending due to the tension from the stepper motor belts. These are things I will correct when I publish the whole thing. On the whole, it is not as sturdy and rigid as my thrustmaster t16000m. Still acceptable though.

On the plus side, I was pleasantly surprised of the feel of the belt sliding over the throttle stalks. The rubber gt2 belt over the plastic seems to have similar coefficient of static and dynamic friction, meaning that there is less 'stiction' than for example my t16000m. I find the 'stiction' on my thrustmaster to be somewhat of an annoyance when trying to get very fine control of the throttle, either on final approach or a2a refuelling. I know there are workarounds with niogel etc and i have tried these but it still not great. I compare it to for example my dobsionian telescope that I built, where the feel is utterly buttery smooth - this throttle approaches that.

Making a start now on learning arduino. Will get the wing sweep handle printed next week.

[Yogi8]

Oh man! I know exactly what you're talking about with the "stiction." It's something that has drove me nuts with off the shelf HOTAS units. I'm not sure I'd classify mine as "buttery" smooth but it was one of the points that I NEEDED to improve. As far as improving how sturdy it feels, would you say it's because of wall thickness or because the entire unit slides around a bit? If it's the latter I have a simple solution that involves a desk clamp for microphones. I plan on modeling/3d printing this fix over this week and I'll post pictures. Keep up the work man! I'm really excited to see your autothrottles in action!

Your emergency wing sweep cover looks dope as hell! I'm jealous

As far as the EWS handle, I model everything in Fusion 360. I can send you those files if you'd like or send you the STLs. Maybe save you some time modeling or at least hurry you along the process, instead of spending 30 hours modeling, printing, prototyping, losing hair, printing again... you know the process. Let me me know.

Edited November 5, 2023 by Yogi8

[Gareth Barry]

Hi Yogi

Let me say that your stunning throttle helps provide motivation for me to finish mine! I have looked at your throttle extensively and stolen ideas here and there, so don't worry about sending me the files, i would have re-engineer the whole thing anyway to fit mine- i seriously appreciate the offer though!

And you are right re the whole thing sliding around- I clamped it down firmly and the whole thing felt a heck of a lot sturdier. However, the problem I think is the 3d printed stalks, they seem to have some flex in them. I will need to increase the sturdiness of those I think.

In terms of stiction, if I hadn't planned on going with functional autothrottles, I probably would have used the same system that is used on my dobsonian mounted telescope - ie a pair of teflon pads on a slightly 'pebbled' surface such as formica. 

And now, some progress electronically. I have been learning about dcs bios, but more so how to use arduino in general. I got the throttles moving backwards and forwards using the inbuilt stepper function in the arduino. The results were slightly disappointing, these steppers seem just barely adequate in terms of torque. Anyways, I will keep fiddling with the code, power supply, and perhaps go to the 9v versions of the same stepper motor. I also managed to figure out how to read in an analogue voltage and print out a serial number based on that. 

So the plan for now is to get to a system whereby I use both this throttle and the new one as a test - I will hook up DCS bios to give out the position of the throttles when in autothrottle, which will energise the stepper motors, which will start moving the levers on the new throttle, whilst the t16000m is stationary. From there I will try to combine both functions into one.

Should have the main handle printed sometime this week.

 

[RustBelt]

Put the steppers on a separate dedicated stepper drive board connected to the Arduino. You'll be able to realize much finer stepping, and some more power. Running as a DCSbios controller you could use the auttothrottle flag to "disable" the throttle output so DCS doesn't KNOW the throttles are moving. But when you come off autothrottle the levers are where they belong. But that makes it a fully dedicated DCS peripheral. 

[Gareth Barry]

Hi Rustbelt

Your idea as you outline the general coding is essentially exactly how I was going to implement it. My idea was to use a leonardo instead of my current uno, as my understanding is that it's easier to implement it as a joystick. I thought of just using the uno and communicate the throttle position directly through DCS bios, but i like the joystick libraries such as unojoy, and I can at least then calibrate the thing easily. Obviously I would have to add lines of code in order to communicate with DCS Bios as well as get the autothrottle and wingsweep working. Having said that, I have no intention of making this a general use throttle for anything other than DCS with the Tomcat - I hardly ever play IL-2 and mastering the Tomcat is honestly taking up all my sim time.

For steppers I am using the typical ULN2003 driver, and tried powering it with its own supply instead of through the arduino, which didn't seem to make much difference to the amount of torque produced. I preferred powering it with its own supply, less chance of blowing the USB on my PC.

I have been some reading in terms of gaining more torque form these things (28 BYJ steppers), as I understand it, my options are;

1. run the whole thing at a higher voltage, and make sure that there is enough pause/time delay in the loop to let it cool down some between steps

2. run it as a bipolar stepper ommiting one of the wire taps, but that would require using a more expensive driver

3. Actually write out the code to send voltage to each tap(s) in sequence in order to step the motor, and in doing so, send 'high' to 2 taps at once during each step. This should increase the torque somewhat.

Going to fiddle tonight and see. 

I feel that I am somewhat on the right track.

 

[Gareth Barry]

OK so, I managed to get far more torque from the stepper motor without having to mod the stepper motor itself, essentially from better coding. The speed of movement of the throttles is perfect, as is the ease at which they can be overridden by hand. Overall I am extremely pleased to this point, despite taking a whole day to figure out how to get the halll effect sensors to work properly and breaking 2 of them!! In the end it basically came down to needing a stronger magnetic field.

So now I am at the point where I am trying to get to know DCS BIOS and I have hit an immediate roadblock - I can't even get it to open! My firewall (I think) seems to be blocking it - it won't let the program 'listen on tcp port 5010' or some such. I have tried unblocking it on the advanced settings, bo matter what I do I can't get it to work. Any ideas?

 

Ok; I'm a dumbass...it was open on the bottom taskbar lol!!

Edited November 7, 2023 by Gareth Barry

[Elo]

15 hours ago, Gareth Barry said:

OK so, I managed to get far more torque from the stepper motor without having to mod the stepper motor itself, essentially from better coding. The speed of movement of the throttles is perfect, as is the ease at which they can be overridden by hand. Overall I am extremely pleased to this point, despite taking a whole day to figure out how to get the halll effect sensors to work properly and breaking 2 of them!! In the end it basically came down to needing a stronger magnetic field.

So now I am at the point where I am trying to get to know DCS BIOS and I have hit an immediate roadblock - I can't even get it to open! My firewall (I think) seems to be blocking it - it won't let the program 'listen on tcp port 5010' or some such. I have tried unblocking it on the advanced settings, bo matter what I do I can't get it to work. Any ideas?

 

Ok; I'm a dumbass...it was open on the bottom taskbar lol!!

 

Word of advice, if youre starting out new with DCS BIOS i would recommend you use the Flightpanels (now Skunkworks) branch, since its still being actively updated. It lacks the fancy GUI of the main branch though.

https://github.com/DCS-Skunkworks/dcs-bios

[Gareth Barry]

Thanks Elo

Perhaps you can clarify - my (mis?)understanding was that flightpanels is specific for interacting with saitec equipment? When I was looking through the DCS BIOS commands for the f14 I was very surprised to see that there is nothing for the throttle position on autopilot - so I was thinking of getting that indirectly from eg the engine rpm or fuel flow?