Problem with 3Gx and Co-Pilot 2 Help if possible please

[Ossibong]

Hi,

I have recently installed a co-pilot 2 system to a TRex450 3GX FBL and I cannot get the co-pilot to operate correctly.
I initially had trouble because I tried to install the co-pilot without a receiver, but having installed a 8 channel receiver, I have wired up the co-pilot prior to the 3GX system.
The heli flies fine till I turn on the co-pilot, and it plunged to the ground head first - did massive damage as you can imagine.

I have checked and re-checked the wiring and it is fine, I have been through the quick setup on the co-pilot - centred the stick, selected everything as per the video of how to and it still does it.

If I have the heli sitting on the table, turn it on, it is fine and stable, turn on the co-pilot (via the mode 1 and mode 2 switch) - I have it set for level flight, as soon as I switch to Mode 1 the swashplate plunges sideways (to the right) and hard backwards.

If I disconnect the co-pilot on off switch from the receiver, switch modes, the swashplate is stable as. Plug in - turn the mode switch to mode 1 - swashplate plunges.

Can anyone help me re if there are any special settings you need to do the co-pilot setup with a flybarless system???

I have just about gone nuts putting this co-pilot onto this 450 - major drama so far anyway.

Appreciate any help anyone can offer.

Thanks

[nightflyr]

Not sure what you have done ...

The basic setup is..

Rx>>>>>CPII>>>>>FBL>>>>>servos

It sounds as if you have something cross wired somewhere along the path.

Suggest you disconnect everything and wire up one signal pathway from the RX through to the servo one at a time from start to finish.

[Ossibong]

Dear Nightflyr,

Thanks for the help, I have checked and re-checked the wiring - taken the co-pilot off and re-done with one wire at a time - and still no joy, does same thing.

I am a little concerned that the wiring that the 3GX system uses from the receiver and in my case from the co-pilot of only having one wire - (signal only and no positive or negative) might be the reason the co-pilot doesn't work. The 3Gx uses a multi plug arrangement for all inputs - three per plug.

The heli flies fine without the co-pilot turned on, which verifies the connections (I did have elev and ail swapped in the co-pilot early on and you could tell as they were incorrect on test) - once this was corrected there is no issue with the heli itself.

I attach a connection diagram if you can understand it - it is pretty rough and ready! - would really appreciate your input/comment.

Cheers

[nightflyr]

The connections appear correct, did you check that all polarities are right.

CPII and 3GX does work together, it has been done but the only issue was a bad SAT receiver @ the time.
My next suggestion would be to remove the 3GX and wire up the CPII to verify the CPII operation on the bench.

[Ossibong]

Yep,

polarity all good - as I said the actual heli works fine with the co-pilot off.

If I put the co-pilot on, the swashplate goes down and to the right, I can actually move my hand around the tail sensors and the swashplate moves - up, down and does move as I move my hand past the sensors, both on the tail and the vertical up sensor.

my tail sensor is mounted just in front of the small tube fin, I have taken the fin off thinking it might have been interfearing with the sensor, but no difference.

I have made a small video of it, but I don't post on utube or whatever, so probably not able to get it to you.

I am pretty well stumped at this point.

Cheers

[nightflyr]

According to your explanation, the CPII appears to be functional.....

As I said test it without the 3GX and see if you still get the swash deflection, if it works then it may be due to the fact of missing Gnds leads

[Ossibong]

Will do - let you know how it goes
Cheers

[Ossibong]

I have taken out the 3GX from the system - put the servo's directly into the co-pilot -

works a treat - much quicker than through the 3GX with the reaction from the sensors much quicker.

Does not do the swashplate plunge - but:

I have checked my 500 FBL it is a FL760 Align system, and it has only signal wires for the Pitch and the Elevator, with the Aileron having a full three wires.

I am pretty sure the co-pilot works fine on these systems, so I am not sure of the difference, unless taking (or bringing) a positive and neg with the alileron wiring lets the co-pilot function correctly, wheras the 3GX doesn't have any + - on the servo side at all?

Confused now for sure.
Cheers

[nightflyr]

Ok,
Now that you proved the CPII is fully functional, and the 3GX is functional as well..
Time to find out where the issue is in the wiring..

Here I suggest you start hooking one cyclic up at a time and test it out, it may be that once you get all 3 hooked in you loose control which may be due to noise on the signal paths.

By chance what Tx are you using?

[Ossibong]

I am using a DX8

Late here, crashing now, will do as you suggest tomorrow and post outcome.

I am also considering getting a + and - to servo side of co-pilot to test that theory as well

Cant see that it would do any harm.

Thanks for your help,

Cheers

[nightflyr]

Might also look at this too..

https://www.helifreak.com/showthread.php?t=359843

[itshel]

Originally Posted by Ossibong

Hi,

I have recently installed a co-pilot 2 system to a TRex450 3GX FBL and I cannot get the co-pilot to operate correctly.
I initially had trouble because I tried to install the co-pilot without a receiver, but having installed a 8 channel receiver, I have wired up the co-pilot prior to the 3GX system.
The heli flies fine till I turn on the co-pilot, and it plunged to the ground head first - did massive damage as you can imagine.

I have checked and re-checked the wiring and it is fine, I have been through the quick setup on the co-pilot - centred the stick, selected everything as per the video of how to and it still does it.

If I have the heli sitting on the table, turn it on, it is fine and stable, turn on the co-pilot (via the mode 1 and mode 2 switch) - I have it set for level flight, as soon as I switch to Mode 1 the swashplate plunges sideways (to the right) and hard backwards.

If I disconnect the co-pilot on off switch from the receiver, switch modes, the swashplate is stable as. Plug in - turn the mode switch to mode 1 - swashplate plunges.

Can anyone help me re if there are any special settings you need to do the co-pilot setup with a flybarless system???

I have just about gone nuts putting this co-pilot onto this 450 - major drama so far anyway.

Appreciate any help anyone can offer.

Thanks

i have had exactly the same problem did all the things you did, though with a Trex 550e 3g. and the solution was, and has worked continuously since. when the swash is angled as you described, go to copilot flight angles and adjust these so the swash becomes level. that did it. I can do any other adjustments I like, and everything works fine.

[Ossibong]

Hi itshel,

I am just about at the same point as you - that seems to be the only thing left to do, because it does not look like anything else makes much difference.

I will give your suggestion a try and see if it then behaves itself.

I wish I had actually tested before I tried it in flight - cause is sure hurts when it dives straight into the ground nose first! ha ha

Will post the outcome

Cheers

[Ossibong]

All,

I have tried as suggested by itshel, and the amount of adjustment my swashplate needs is way outside the amount of flight angle adjustment in the co-pilot. The flight angle adjustment is designed to take out any small variances in the mounting of the sensors to get level flight. This is much bigger than that - hard down backwards and to the right -

I have tried the co-pilot on it own, bypassing the 3GX - set it up and it works fine - responsive and no problem at all with the swashplate issue.

The 3GX works fine on its own, so I have come to the conclusion that they are not comparable - at least that is the way it looks to me.

I thought the fact that there was no + - on the servo side of the co-pilot, because the 3GX uses only signal cable from receiver to 3GX, I run a + - from the receiver to the servo4 plug that I am not using on the co-pilot to make sure there was + - on that side - made no difference.

I have checked out my DX8 Tx - there is no issue with the trims - they are spot on

I actually thought it was working last night, but it turned out I didn't have enough light difference on the sensors and it was basically turned off - even though I had it turned on - I hadn't run a pre-flight check.

I have written to technical support from FMA - so hopefully they will come up with a fix, or confirm my current outcomes, either way I will post for everyones info.

Cheers

[Adventurer]

Two thoughts:
1. Voltage supply. Have you checked that your BEC can drive both units? Maybe there's enough voltage sag to reset the CP-II processor.

2. Noise. This is out there on the fringes of possibility. The one thing that CP-II does not like is electrical noise. I'm wondering if that 3GX unit is leaking noise of some kind. If you have a seriously big capacitor lying around you could connect it across the + and - supply to CP-II and see if makes a difference.

[Ossibong]

Firstly,

I don't have a BEC - just a supply from the ESC - and maybe that is one potential problem,

Secondly, the supply to the receiver - comes via the 3GX system - as in it takes the supply from the ESC, then it goes to the receiver, then I guess the co-pilot gets its supply from the receiver.

Long way round, especially if the ESC supply is a bit under pressure, and if the 3GX is putting some noise into the system by taking the suppy first -

I think I will get a BEC as soon as and see if it makes any difference -

Appreciate the thoughts, they sound feasable as the co-pilot works on its own as does the 3GX - maybe the combination is too much for the ESC supply.

Keep all posted.

Cheers

[Ossibong]

Second thought, I have not been using the ESC supply in testing this out, I have been using a NiMH battery that is fully charged.
I think I will seperate the supplies and put the ESC supply as the feed to the 3GX system and put the battery supply into the receiver direct, and see what happens.

This should potentially alleviate both issues as the supply to the receiver will be sufficient, untouched by the 3GX and the supply should be clean of any noise as it is seperate to the 3GX - if this works, I will then put a BEC supply into the receiver/co-pilot.

WIll post outcome shortly

[Ossibong]

Adventurer,

That solved the problem - thank you a whole heap!

Put the battery into the receiver, ESC supply into the 3GX and it looks to be working fine on the lawn, wires hanging everywhere!! - but no plunging swashplate and reacting to the sensors as it should etc.

It looks to be resolved to me.

I don't know much about BEC's but would I be able to leave the ESC supply into the 3GX system and use the BEC into the receiver as in would it all turn on at the same time etc?

Thanks again

[Adventurer]

I'm happy that you've found it.

As to using multiple supplies (ESC + BEC), the pundits will tell you that it will not work, and that you need to purchase a BEC big enough to drive the whole shootin caboodle, or use a receiver battery. I think that a seperate receiver battery is overkill on a 450.

I once asked why I can't use two BEC's in parralell and was told that they would fight. Something vague about switching. I remain unconvinced, but have not tried it.

Edit: The power supply is bussed though the whole bird via the servo leads and common rails in the receiver and Co-Pilot (dunno about 3GX). So, I think you were running you internal BEC (inside the ESC) and the pack in parralell. I don't know what the voltage of that NiMH pack that you're using is (I could look it up but I'm lazy), or what it's charge voltage is, so I'd suggest that you check those out before you fly this configuration for too long. You may have been running only on the pack, or you could have been charging the pack from the ESC.

[Ossibong]

I guess the fighting might make sense as two BEC's would be potentially switching at different times (to give out a reduced voltage) - I have seen postings of the 3GX system using the supply from the ESC and also putting in a BEC supply to the power in side of the 3GX at the same time, so I think it is possible.

I was more concerned regards noise - because maybe that is the issue, but if I have one bigger BEC that can give a constant supply, at a rated current rather than a ECS supply that from what I read can be sus on actual rated output, I will probably have it licked.

Once I track down a BEC and give it a try I will post the outcome - and hoefully it is all good!

Thanks again,

Cheers