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Throttle cut using logical switch. (abandoned).

Posted: Fri May 17, 2019 5:23 am
by ThompsonJim
I have run out of channels and would like to set up a logical switch to operate ignition cut. (Throttle cut).
I have an opto switch for that function in my model.
Can someone describe how I might set this up in my new Taranis X9D plus?
I have never programmed a logical switch before.

Edit:
I have started to think up an answer to my own question.
As there is no channel left available for the throttle cut, it will need to be operated on the same channel as the main throttle servo.
So, maybe the following set up will work ok:

1. Make the throttle servo pushrod out of a rod and telescopic tube. The tube will function against a stop on the rod for throttle actuation. The carb spring will hold it against the rod; if it is too weak, add another spring.
2. This will allow the servo to be operated beyond the engines idle lower limit. (The tube then slides away from the stop on the rod).
3. The lower limit of the channel signal drive will then form one parameter of the logical switch.
4. The other parameter will be a physical switch.

The requirements to meet the conditions for turning off the ignition will be throttle stick down and a specified switch activated.
Is there a simpler way?

Edit: The simplest way might be to reverse one of the flap servos. It could be then operated on the same channel (1 flap instead of 2 flap).
I have reversed one of the elevator servos for the same reason, to I know how to do it.
That would liberate one channel to allocate for the throttle cut.

Jim.

Re: Throttle cut using logical switch.

Posted: Fri May 17, 2019 1:10 pm
by thebriars0
Jim
Have a look at my documentation on this forum.

viewtopic.php?f=45&t=8724

If you go to the How To part 1 section there is a throttle cut there.

Not sure what you mean by no channels left, I presume you mean receiver channels, as there are loads of transmitter channels. This throttle cut does not need any receiver channel and is mainly designed for electric, but could easily be adapted for IC if you don't let the throttle go to -100 on tickover, but somewhat higher say -80.

This throttle cut is almost foolproof, not only does it need the throttle to be below a certain level (you would have to adjust this to say -80), but you have to hold the switch on for a specific time, i.e. between 3-5 seconds. Thus accidentally knocking the switch in flight will not activate it even with the throttle closed. I also have a bleep programmed every second, so it is easy to time the switch. If you do gain a receiver channel back, you could still use this to operate the spare channel.

Just one way.

Martin

Re: Throttle cut using logical switch.

Posted: Fri May 17, 2019 1:36 pm
by tonnie78
I would choose to expand the number of channels. For the price of a receiver or if posdible an Sbus converter you cab hardly make any mechanical changes

Verstuurd vanaf mijn SM-G973F met Tapatalk


Re: Throttle cut using logical switch.

Posted: Fri May 17, 2019 10:33 pm
by ThompsonJim
thebriars0 wrote: Fri May 17, 2019 1:10 pm Jim
Have a look at my documentation on this forum.
viewtopic.php?f=45&t=8724
If you go to the How To part 1 section there is a throttle cut there. ..................
Excellent explanation, thank you very much!. I thought that's how it could be done, but I am totally puzzled about the icons used in the logical switches window. I have searched for a glossary of symbols or icons, but could not find anything in any of the manuals, including my hard copy.
Can you direct me to one please?
Please note; if this is in your documentation, I have not yet found it and I have only scanned through quickly. I will read it all more thoroughly tonight.
Not sure what you mean by no channels left, I presume you mean receiver channels,........
Martin
I much appreciate you taking the time to write the above documentation and taking the time to answer me.

Jim.

Re: Throttle cut using logical switch.

Posted: Fri May 17, 2019 10:38 pm
by ThompsonJim
tonnie78 wrote: Fri May 17, 2019 1:36 pm I would choose to expand the number of channels. For the price of a receiver or if posdible an Sbus converter you cab hardly make any mechanical changes
Thanks for that suggestion tonnie.
That would be a good solution too. However, I am not at all conversant with the Sbus system and would need to learn that all from scratch, along with the OpenTx/Taranis programming and operation (which is challenging me sufficiently for the time being). Also, I like to use the very good "D" series receivers that I already have; I am a pensioner on a budget and also a bit parsimonious.
I expect that in the fullness of time, I will likely progress to using the Sbus system. But not yet.
Can you direct me to a succinct introductory tutorial on the Sbus system?
That would be much appreciated.

Thanks,

Jim.

Re: Throttle cut using logical switch.

Posted: Sat May 18, 2019 1:52 am
by ThompsonJim
thebriars0 wrote: Fri May 17, 2019 1:10 pm Jim
Have a look at my documentation on this forum.

viewtopic.php?f=45&t=8724
................................
Martin
Martin,

Once again, its a very well presented guide you provide.
However, I did follow the instructions on page 33 very carefully, but could not get it to work as it should.
The result I am getting is this:
1. When I move the throttle stick to zero, the opto engine cut switch turns off.
2. When I change the throttle weight to +100 instead of -100, the opto engine cut switch turns off at max throttle.
3. Switch 3 SE has no affect whatsoever regardless of the stick position.
4. Also, it appears to be unstable, but that just might be me stabbing around.

What have I done wrong?
If necessary, I can load this into my Companion app tonight and post a screenshot.
Please note: my entry or entries into the second line for the throttle shows a "+=" in the place where yours shows ";="....
Does this make any difference?
Thanks,
Jim.

Edit: I have just come back to it again. I've confirmed that it is functioning in an unstable way and operates the cut switch in a random fashion.
Something wrong here...............?
I deleted line 2 in the throttle line in the mixes menu. I then confirmed that the cut switch operates ok. All good there.

Re: Throttle cut using logical switch.

Posted: Sat May 18, 2019 5:39 am
by ThompsonJim
Screenshots of my Entries (following instructions @ page 33 in Section 9.......) shown in Companion.

Re: Throttle cut using logical switch.

Posted: Sat May 18, 2019 12:08 pm
by thebriars0
Hi Jim
Almost sure the error is in a little bit you highlighted.

...... shows a "+=" in the place where yours shows ":="....

This is the multiplex feature on the mixer. The "+=" means add the line to the previous one. The ":= " means replace.
Replace.JPG
On the mixer the throttle setting is normally -100. What this line does is replaces this throttle setting with the normal setting linked to the throttle joystick. You will get something odd happening if you simply add them.

It is explained in section 5, The Model Editor, page 28 although looking at it now, it could be presented better, and it would be useful to show the transmitter screen symbols.

The icons for the Logical Switch Window are given in the Model Editor pages 45-48.

As you are finding, there is an awful lot to OpenTX, its great when you are used to it, but can be difficult at first!

Re: Throttle cut using logical switch.

Posted: Sat May 18, 2019 12:25 pm
by ThompsonJim
Very good Martin, thanks for the reply. I will try it again now.

Re: Throttle cut using logical switch.

Posted: Sat May 18, 2019 1:10 pm
by ThompsonJim
thebriars0 wrote: Sat May 18, 2019 12:08 pm Hi Jim
Almost sure the error is in a little bit you highlighted.

...... shows a "+=" in the place where yours shows ":="....

This is the multiplex feature on the mixer. The "+=" means add the line to the previous one. The ":= " means replace..................
That makes sense to me. It goes part way to explain how it works.
The icons for the Logical Switch Window are given in the Model Editor pages 45-48. ...............
I fill follow that up tomorrow..............late now and I'm very tired.
As you are finding, there is an awful lot to OpenTX, its great when you are used to it, but can be difficult at first!
I made the changes from "add" to "replace". Checked everything twice, then tried it out.
It function exactly the same as before.

The option of changing the direct of one servo and running the two flaps off the one receiver channel is looking more and more attractive by the minute!

I will check in again in the morning.
Thanks for following up for me; there must be something very silly that I am doing wrong.

Jim.

Re: Throttle cut using logical switch.

Posted: Sat May 18, 2019 2:07 pm
by thebriars0
Hi Jim

Look at L02. You have put !L03 each time instead of L03.

The ! in front means, L03 is not true.

You might need to check everything, as sometimes ! is used and sometimes not.

Its a bit annoying, OpenTX lists all the ! options before the normal options. You need to scroll down the list further.

Re: Throttle cut using logical switch.

Posted: Sat May 18, 2019 3:46 pm
by jhsa
Jim, are you able to do soldering and program Microcontroller chips or arduino boards?
Also, are all channels used for control surfaces, or are some being used for other stuff like lights for example?
I am asking because there is an electronic project that allows us to control different equipment from just one channel of your receiver. But you would have to build it :)

viewtopic.php?f=84&t=7299

João

Re: Throttle cut using logical switch.

Posted: Sat May 18, 2019 9:21 pm
by ThompsonJim
jhsa wrote: Sat May 18, 2019 3:46 pm Jim, are you able to do soldering and program Microcontroller chips or arduino boards?..................
Yes Joao.
I have made some arduino projects before. Life long electronics experience.
Also, are all channels used for control surfaces, or are some being used for other stuff like lights for example?..........
One is being used for and emergency aerotow release. The model I am working on will be a glider tug plane.
I am asking because there is an electronic project that allows us to control different equipment from just one channel of your receiver. But you would have to build it :)
viewtopic.php?f=84&t=7299
João
Thanks Joao, I will have a look.

Re: Throttle cut using logical switch.

Posted: Sat May 18, 2019 10:11 pm
by ThompsonJim
thebriars0 wrote: Sat May 18, 2019 2:07 pm Hi Jim
Look at L02. You have put !L03 each time instead of L03.
The ! in front means, L03 is not true.
You might need to check everything, as sometimes ! is used and sometimes not.
..........................
Martin,

Got that. I have corrected it and learned something along the way. I have triple checked all entries again.
However, the result is precisely the same as before, except that it is stable.
I need to check with you if the symbols I am reading in my tx are the same as yours.
1. I see an option to enter L03 where you see L3. Are these equivalents?
2. In your screenshot from (I assume) Companion of the what the mixer shows, you see a source as something like: [I1] or [I2] or [I3} etc. whereas, I only see a black background capital letter I in my transmitter. (I understand that this is the source selection indication and in this case is "Inputs".......correct?).
If I am interpreting what I am seeing correctly, I read at least three different symbols to indicate "inputs" selection. The third one is in the printed manual written by Lothar Thole. He prints a symbol that looks like a 45 deg angled arrow with a little part border.
Are these all meant to indicate the same source?
Or, are they indicating different things?
Extra challenging for the beginner to say the least.

Still a long way from getting it to work, I suspect.
Have you tested this in practice? (forgive me for asking...........I don't mean to be rude).

Thanks again,

Jim.

Re: Throttle cut using logical switch.

Posted: Mon May 20, 2019 5:48 am
by ThompsonJim
I must have spent in excess of 6 hours on this one mix, without any sign of success. I have tried it in the transmitter and in Companion in two separate operating systems; Linux Mint 19 and in Win7. Same result all round.
I have tried juggling parameters, entering offsets and other little changes. No good.
It appears that the author - Martin - is not available or not willing to assist further.
I will abandon it and resort to the option of reversing a servo for my immediate needs. I have a deadline to get my current tug plane built, registered and operational for an upcoming event.

I will now edit the opening post title accordingly.

Thanks,

Jim.

Re: Throttle cut using logical switch. (abandoned).

Posted: Mon May 20, 2019 8:22 pm
by thebriars0
Jim

I have used this for several years on all my small models and it works fine, last used on Saturday.

Just programmed it into Companion and again it works perfectly. Took my 5 minutes to enter it again. The operating system you use with a PC will make no difference.

On one of the updates, OpenTX changed L1 to L9 to L01 to L09. It would have taken days to take new screenshots of all the times this occurs and update the documentation.

Re: Throttle cut using logical switch. (abandoned).

Posted: Mon May 20, 2019 9:59 pm
by ThompsonJim
Ok Martin. It must still be something I am not seeing or doing right.
Thanks for returning to confirm that for me.
I am not clear on the principle in terms of the servo signal generated in both states according to switch SE(down).
What signal does the servo receive at all states and what signal does the (in this case opto switch) receive in both states?
It will help me for later attempt to get another logical switch set up to understand. I will need engine temp (high) to limit part throttle for example.

I reversed a servo and refitted it, paired the signal wires to both servos at the rx. in less than an hour last night. So, I have the flap function and opto engine kill switch working (on the vacated rx channel) all ok.

Jim.

Re: Throttle cut using logical switch. (abandoned).

Posted: Tue May 21, 2019 1:29 pm
by thebriars0
Basically this routine has no direct effect on the servo whatsoever.

All it does is sets the throttle channel to -100 no matter where the throttle stick is. Then once switch E is held down for between 3 and 5 seconds AND the throttle stick is fully down it will enable the throttle stick to work again. If the throttle is enabled, it works exactly the same to disable the throttle.

In the mixer page, L02 acts on the throttle input to disable or enable the input from the throttle stick.

Re: Throttle cut using logical switch. (abandoned).

Posted: Tue May 21, 2019 5:05 pm
by jhsa
I have been following this thread and i got the feeling that there is some misunderstanding here.
What I think he wants is:
As an example, his throttle servo MIN / MAX movement ranges for example from -60% to say +80%. So at idle will be -60%
He did a mechanical implementation with some kind of spring that allows the servo to move further down while the throttle arm is at minimum (Idle). With this he could activate a mechanical switch?? (This isn't very clear to me).

Jim, what does your ignition switch need to see from the radio.. How do you normally turn it ON or OFF? Is it mechanical? or with a signal from the radio? If this is the case, what kind of signal? (percentage, pulses, etc)

My Tony Clark Piper Cub, 62cc petrol engine, also a tow plane, has an ignition system that receives a signal from the receiver, so, it needs to be connected to a channel of that same receiver..

João

Re: Throttle cut using logical switch. (abandoned).

Posted: Tue May 21, 2019 7:13 pm
by thebriars0
Basically the OP wanted a throttle cut without using extra receiver channels, and wanted to do this using logical switches. My suggestion was to have engine idle set at about -80 and use a software throttle cut which would set the throttle at -100 and thus stop the engine.

Re: Throttle cut using logical switch. (abandoned).

Posted: Tue May 21, 2019 9:28 pm
by jhsa
I understood that it is a petrol engine, and there should be an ignition system that is controlled by the radio, just like on my plane

João

Re: Throttle cut using logical switch. (abandoned).

Posted: Tue May 21, 2019 10:21 pm
by ThompsonJim
thebriars0 wrote: Tue May 21, 2019 1:29 pm Basically this routine has no direct effect on the servo whatsoever.

All it does is sets the throttle channel to -100 no matter where the throttle stick is. Then once switch E is held down for between 3 and 5 seconds AND the throttle stick is fully down it will enable the throttle stick to work again. If the throttle is enabled, it works exactly the same to disable the throttle.

In the mixer page, L02 acts on the throttle input to disable or enable the input from the throttle stick.
I am sorry Martin, but I cannot understand one sentence of the above description!

Edit: That is not completely true. I do understand the first sentence.

Re: Throttle cut using logical switch. (abandoned).

Posted: Tue May 21, 2019 10:27 pm
by ThompsonJim
jhsa wrote: Tue May 21, 2019 5:05 pm ...............................
He did a mechanical implementation with some kind of spring that allows the servo to move further down while the throttle arm is at minimum (Idle). With this he could activate a mechanical switch?? (This isn't very clear to me)..................
I never went so far as to set that method up Joao, I was only discussing it as an option. More about that later if you wish.
Jim, what does your ignition switch need to see from the radio.. How do you normally turn it ON or OFF? Is it mechanical? or with a signal from the radio? If this is the case, what kind of signal? (percentage, pulses, etc).............
It is an opto isolated ignition switch, common to many spark ignition, internal combustion engine installations. It is now connected to it's own channel in the receiver, just as yours is in your description below.
My Tony Clark Piper Cub, 62cc petrol engine, also a tow plane, has an ignition system that receives a signal from the receiver, so, it needs to be connected to a channel of that same receiver..
João
Thanks,
Jim.

Re: Throttle cut using logical switch. (abandoned).

Posted: Tue May 21, 2019 11:13 pm
by jhsa
Jim, I am just trying to understand what you want to achieve so we know how to help you :)

João

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Re: Throttle cut using logical switch. (abandoned).

Posted: Tue May 21, 2019 11:36 pm
by ThompsonJim
jhsa wrote: Tue May 21, 2019 11:13 pm Jim, I am just trying to understand what you want to achieve so we know how to help you :)
João
Yes, I fully understand.
I am trying to set up my Taranis X9D Plus to fly my new tug plane.
It is a 1/4 scale Spacewalker. Powered by an internal combustion engine.
Two ailerons, two flaps (operated now from one receiver channel).
Rudder.
Elevator
Throttle
Emergency aerotow release.
Opto isolated, purpose designed, engine cut switch. Now operating fine on it's own channel.

Thanks for assisting.

Jim.

Re: Throttle cut using logical switch. (abandoned).

Posted: Wed May 22, 2019 12:23 am
by jhsa
Ok, than you have solved the problem. The thing is, unless the switching point of the engine killer switch could be programmed, you couldn't use the throttle channel.
If you could program the switch to switch at a given pulse from the receiver, then it could be possible to do it using the same channel as the throttle, if your throttle servo didn't use all the available range. For example, the normal channel travel on your radio is -100% to +100%. Now imagine that your throttle servo only needed to travel from -60% to + 80%. You could use some lower value to trigger the switch, for example -90%. But, you would need that mechanical solution of yours to avoid the throttle servo being damaged. The radio programming would then be fairly simple. And also, this would only work if your switch has a programmable switching point. Otherwise it would need a dedicated receiver channel.. My plane has one of those "Power Boxes" (I thing that is how they are called in English?) that has it's own channel expander. for example you have the ailerons only on one single channel on the radio, and the expander outputs 2 aileron channels.
I think you found the easiest and cheapest solution for the problem though :)

João

Re: Throttle cut using logical switch. (abandoned).

Posted: Wed May 22, 2019 5:07 am
by ThompsonJim
jhsa wrote: Wed May 22, 2019 12:23 am Ok, than you have solved the problem. The thing is, unless the switching point of the engine killer switch could be programmed, you couldn't use the throttle channel.
If you could program the switch to switch at a given pulse from the receiver, then it could be possible to do it using the same channel as the throttle, if your throttle servo didn't use all the available range. For example, the normal channel travel on your radio is -100% to +100%. Now imagine that your throttle servo only needed to travel from -60% to + 80%. You could use some lower value to trigger the switch, for example -90%. But, you would need that mechanical solution of yours to avoid the throttle servo being damaged. The radio programming would then be fairly simple. And also, this would only work if your switch has a programmable switching point. Otherwise it would need a dedicated receiver channel.. My plane has one of those "Power Boxes" (I thing that is how they are called in English?) that has it's own channel expander. for example you have the ailerons only on one single channel on the radio, and the expander outputs 2 aileron channels..................
Are the two ailerons then able to be trimmed separately? Or does this unit function like a simple "Y" lead?
I think you found the easiest and cheapest solution for the problem though :)
João
I may have. I still have a minor problem to sort, but nothing that is urgent.
I am unable to set offset for my flap servos in the OpenTx 2.2.2
More accurately, I can set offset, but it only works in one direction.
But,,,,,,,,,,,,,this is a matter for another thread. Here for your possible interest: https://www.rcgroups.com/forums/showthr ... ed-channel
&
https://www.rcgroups.com/forums/showthr ... -Continued

Many thanks for your assistance and moral support!
I have been suffering from Taranis induced low morale (more accurately described as depression) for some time. I've turned the corner this morning, Thanks to you, Miami Mike and others.

All the best to you,

Jim.

Re: Throttle cut using logical switch. (abandoned).

Posted: Wed May 22, 2019 8:42 am
by jhsa
I am not sure, that model was a present from a friend, and it was already setup, but I think it is programmable.

Thank you for the links.

The Taranis might be a steep learning curve, but when you have that Eureka moment, you will find out how powerful its programming can be.
My advice is, when you have some spare time, just create a new model and play with it. There are also excellent manuals for OpenTX as far as I know. So having a good look at them might also help a bit :)

João






Re: Throttle cut using logical switch. (abandoned).

Posted: Wed May 22, 2019 10:00 am
by ThompsonJim
jhsa wrote: Wed May 22, 2019 8:42 am ...................
The Taranis might be a steep learning curve, but when you have that Eureka moment, you will find out how powerful its programming can be.........
I just had one of those kind of moments Joao!
I managed to get all 8 servo and switch functions working in my new tug plane using my Taranis X9D Plus. All in the plane that is, and not a mock up on the bench.
Wow! I could hardly believe it when I went through the functions one by one and proved they all worked.
(Don't ask me how I did; I could not account for it myself).
I even achieved 3 rates on a switch for the primary controls!
My advice is, when you have some spare time, just create a new model and play with it. ...........
That is just what I have been doing. Setting up a receiver and servos on my desk in front of me, then programming the tx. to do specific functions.
There are also excellent manuals for OpenTX as far as I know. So having a good look at them might also help a bit :)
João
I have a copy of many, if not most of the ones I have found. The written one from Lothar Thole is not worth a look in my opinion, (I have yet to find a solution to a problem in that one), but some of the online ones are particularly good.
I will go back to take a look at the rest of Martin's manual. Even though I could not get his logical mix to work. I've no doubt the rest of his work is beginner friendly!................. :D

Cheers,

Jim.

Re: Throttle cut using logical switch. (abandoned).

Posted: Wed May 22, 2019 12:23 pm
by thebriars0
ThompsonJim wrote: Tue May 21, 2019 10:21 pm
thebriars0 wrote: Tue May 21, 2019 1:29 pm Basically this routine has no direct effect on the servo whatsoever.

All it does is sets the throttle channel to -100 no matter where the throttle stick is. Then once switch E is held down for between 3 and 5 seconds AND the throttle stick is fully down it will enable the throttle stick to work again. If the throttle is enabled, it works exactly the same to disable the throttle.

In the mixer page, L02 acts on the throttle input to disable or enable the input from the throttle stick.
I am sorry Martin, but I cannot understand one sentence of the above description!

Edit: That is not completely true. I do understand the first sentence.
I think you need to read up carefully on OpenTX. It is very different to programming a normal transmitter, but extremely powerful once you understand the basics. Have you tried working through the "Getting Started" section of the documentation. It is important as it is very easy to not understand something in your programming and then have a real problem during flight.