Assistance required with Taranis x9d+ single stick

[Adrian Harris]

Yes, Mode 1 (RETA).

But I don't think it makes any difference really, as once you've named the Inputs, everything else flows from that.

I also now always configure channels 1 & 2 as the tracks, 3 &4 for the turret, 5 for the sound and then on from there for lights, smoker element, figures etc.

I was surprised, when I used the Companion comparison feature, at just how many different configurations I had between the models, so I spent some time trying to standardise them.

Adrian.

[Jerry Carducci]

As I understand better now Gary's original concern I suppose my own profiles pretty much perform the same way. I do miss the action of the
braked differential transmissions in my 1/10 scale ICE powered models; they were incapable of neutral turns but made pretty good gradual turns without completely stopping one track.

Jerry

Hi Jerry

On tarmac/ pavement the tank drives ok, it is on grass that it struggles and uses way more power. I did three days with an amateur film director and got about fifty minutes per session on grass plus numerous reshoots. That was with everything on including the smoke system. I am aiming to get it turning better on grass so extending the battery life.

Regards
Gary

I've never liked running on grass or weeds, puts enormous loads on the running gear. I remember the original Tamiya 1/16 scale Sherman came with an admonition against running on weed/grass in the form of a comical caricature of a tank sweating and straining going through grass ... As I've limited the high end output on my King Tiger it can get bogged down in weeds. Thinking of a trying a switch to on demand increase output when needed. Lower gearing would be better but impractical to change at this point. Most all the braked differential transmissions I've used have 3 forward speeds and I just love the power available in first gear; the engine might be screaming but the power is quite impressive for such a relatively small machine. Weeds aren't usually a problem for that system; however I still don't like running in them.

I've thought more than once of developing a larger version of that transmission just because of its flexibility. I've already made a smaller version for use in a 1/10 scale Hetzer.

Jerry

[Gary Richardson]

Hi all

The puzzle deepens....

If you were following the thread regarding drive issues when turning and the Taranis settings I have a further problem/update

As it was dry today I decided to take the Tiger for a drive to check if the programming changes had altered the driving.
First I checked the motors and track movements while it was still jacked up and the tracks off the ground. All was well with forward, backwards ,left and right turns and with the stick central and a hard turn initiated both tracks contra rotated. All as per the programming.
I drove the tank onto some asphalt, forwards and backwards were ok if a little jerky. When I tried a turn with little/no forward momentum only the right track was driving the left was static, it didn't matter which direction the turn was, only the right track was driving.
I know think the problem might be with the Motor module A (I have the red units) and the left speed controller is failing under load but is fine when there is very little load i.e. just driving forward. I don't think it is just a mechanical issue (but could be wrong).
I think the problem started while I was doing the filming last year and the tank was being driven on grass and up some quite steep slopes and after that the wet weather meant I didn't do any driving until this year.
Does anyone with experience of speed controllers know if failure under load is possible.
I think the Motor module A is out of warranty and Armortek is closed at the moment otherwise I would contact them for advice. I do however have the Motor Module A for my Churchill which I assume is the same as the Tiger unit. Both sets of motors are pre brushless with the same ratio. I am thinking about swapping out the Tiger unit for the Churchill one to see if the left motor then drives in a flat turn and thus localise the fault. Can anyone foresee any problems if I go down this path ?

Regards
Gary

[Adrian Harris]

Module A has built in current limiting which could be stopping the normal operation but only if there's a really heavy load on that side.

Can you swap the outputs over at the XT60 plugs and see if it only drives the other track ? That would isolate both the track side and the controller side.

Adrian

[Adrian Harris]

One other thing - can you hear a hissing/squeaking noise from Module A under load ?

I've had another one do that and effectively stopping the tank, but I think that was on both sides at the same time, so a unit wide issue.

Adrian

[Gary Richardson]

Module A has built in current limiting which could be stopping the normal operation but only if there's a really heavy load on that side.

Can you swap the outputs over at the XT60 plugs and see if it only drives the other track ? That would isolate both the track side and the controller side.

Adrian

Hi Adrian,

Thanks, I forgot about KISS . I will swap the connectors over this morning to further isolate the problem.

Regards
Gary

[Gary Richardson]

Hi all

I have swapped the XT60 motor connectors over and the problem transfers to the right track not driving under turning load. This would seem to rule out the left motor and indicate the motor module left speed controller has a problem.
I have recently fitted an Ampere monitor and this is what it was reading with the tank driving on smooth asphalt.

Forward and backwards with both tracks driving ok 4A - 6A
Flat turn with no forward or backward momentum 10A - 14A ( One track not moving dependent on which motor is connected)

Now this is where it gets confusing, I removed the left motor and the tracks and final drive rotate freely with no undue noise or binding. Then I swapped out the Tiger module for the one I got for the Churchill and the same problem happens , no drive on the left track when doing a flat turn (under load). Forwards and backwards were ok.
With either module fitted the tracks contra rotate when raised off the ground as per expectations..
I am sure everything was ok when the Tiger was originally set up and the problem has occurred within the last couple of hours of driving.

Regards
Gary

[Adrian Harris]

Have you tried swapping the RX inputs on Module A around to see if the fault moves ?

If it does then the module is just obeying what it's getting from the receiver.

Adrian

[Gary Richardson]

Have you tried swapping the RX inputs on Module A around to see if the fault moves ?

If it does then the module is just obeying what it's getting from the receiver.

Adrian

Hi Adrian
I will try that next. The bit that's confusing me is why it all works ok when the tank is on the jack with the tracks off the ground, but when under load on the ground the problem occurs.

Regards
Gary

[Adrian Harris]

Could it be that the tension on the track is pulling the final drive gear into the side of the hull ?

That wouldn't show up with the tracks off the ground or with the motor removed.

Is there any lateral (in/out) play in the sprocket with the tracks off ?

What happens when you do the same driving tests but with the tank going backwards ?

I have current sensors in the Tiger 131 kit and from memory, straight driving was around 5 to 6 amps, and doing doughnuts on concrete was around 30A.

Adrian.

[Gary Richardson]

Could it be that the tension on the track is pulling the final drive gear into the side of the hull ?

That wouldn't show up with the tracks off the ground or with the motor removed.

Is there any lateral (in/out) play in the sprocket with the tracks off ?

What happens when you do the same driving tests but with the tank going backwards ?

I have current sensors in the Tiger 131 kit and from memory, straight driving was around 5 to 6 amps, and doing doughnuts on concrete was around 30A.

Adrian.

Hi Adrian

I changed the receiver leads over as you suggested and the problem switched to the right track/motor not driving in a flat turn. The left track then did all the driving for the turn. That may rule out the left hand final drive but I will take the track off and check just to be sure as others have said about the final drive gear hitting the side. As you said earlier, the receiver lead swap would suggest the motor module is just obeying the receiver output and as I have already swapped out the module for the unused Churchill one that would also indicate the problem is pre motor module. So you can see why I am confused as to why it works with tracks off the ground and the channel monitor shows the correct outputs.
I will try swapping out the receiver with the Churchill one as I programmed that model from scratch and didn't copy it on the transmitter from the tiger. I will just connect CH2 and CH3 using the Churchill transmitter model . The bench test had the correct motor drive results including contra rotation.

Regards
Gary

[Jerry Carducci]

Hmm. I had thought the track tension might have something to do with it. However i would have also thought that with the tank elevated
and the suspension uncompressed by the model's weight the tension might even have been greater which should aggravate any problem with the final drive gear scraping the hull side?

I would have thought the major contributing factor with the model on the ground would be the model's weight itself. Since the problem appears to move
with some of the tests that seems to point to something not mechanical. Since a module change didn't resolve the problem; perhaps I missed it if it did.

Something seems fishy here. I'd very interested in seeing what the inside of the area around the interior of the final drive looks like.

Would it be possible to make up a simple test model profile in which the forward and reverse as well as steering are controlled by separate sticks?
Just to establish if the level of control desired is at all possible with what's at hand? I assume running with your current configuration with no tracks mounted the sprocket behavior is as you would expect ; as it did with the model elevated.

Once the weather changes I need to get my model out front again where I have more room to see what it does; I already know that running at 30%
of maximum output the model doesn't like to turn through weeds, lawn which is fine as I don't want to tear up my lawn and don't care to do do many turns in weeds. I also have current telemetry and should start logging it for reference. So far I've not seen much more than 6-8 amps draw over all but it might be useful to install current sensors on each motor output if anything like this happens with this model.

Jerry

[Gary Richardson]

Hi all

Firstly, thanks to all those who have contributed to localising the drive problem including those who phoned me to help. I decided to go back to basics and write a list starting with the fault and working methodically through each of the points people had raised. My friend Pat helped set up and verify each step so we didn't miss anything.
I will put the results here as the actions taken may help if someone else has a similar problem.

Problem:
With the tank on the ground and initiating a flat turn with no forward
or backward momentum:........................Left track not driving. Right track is normal drive.

With tracks off the ground and turning as above:...........................Tracks contra rotate in correct directions.

Actions to isolate the problem on electrics and modules:
Each action is done individually.
1) Swap the motor leads over at the XT60 connectors.................... Flat turn, problem transfers to right track not driving.
2) Change the motor module for a different one................ Problem remains the same. L/track not driving in flat turn.
3) Swap the motor module leads over at the receiver............... Problem transfers to the right track not driving.
4) Remove all the servo leads except ch2 and ch3................. Problem remains the same. L/track not driving in flat turn.
5) Swapped the receiver for the Churchill one which was not copied
from the Tiger model................... Tank does flat turn with both tracks driving ( not perfect but using Churchill model )
Actions to check mechanical components:
1) Removed the left hand motor. ..................... Tracks and sprocket wheel turn freely. No metallic residue on gear.
2) Remove L/H track and check Sprocket wheel.................. Sprockets in good condition, turns freely,no side, end play or hull rubbing.
3) Adjust tracks and check suspension.................. Tracks adjusted and suspension ok but will need adjusting soon.

Conclusion:
I tried to cover all the suggestions kindly given to me and as you can see from the above results, it looks like the Tiger model on the transmitter is the most likely candidate although I still dont understand why it works on the jack It could be a receiver problem but I will check that separately.
I will rename the Churchill model and use that and the bound receiver in the Tiger. I will hopefully get that done this moring and once it is running ok I will delete the original Tiger model on the transmitter and write a new one for the Churchill using the receiver that was in the Tiger.
Paul and John both suggested tasking the transmitter and receiver out of the equation by setting the Tiger up on my Futaba transmitter. That would have been the next step after action 5.
I hope to see some of you at the open day with my Tiger , thanks again for your help.
Regards
Gary

[Adrian Harris]

If you want to email me your setup, I could try it in a model here and see what happens.

Using a different TX, RX and model would eliminate a lot

Adrian.

[Gary Richardson]

If you want to email me your setup, I could try it in a model here and see what happens.

Using a different TX, RX and model would eliminate a lot

Adrian.

Hi Adrain

Thanks but I think I have fixed it. I used the Churchill model on the transmitter with its bound receiver in the Tiger and it worked, albeit with the turn reversed. I solved that by reversing the two servo leads at the receiver. The Tiger now responds as expected but will need some fine tuning.
I tried the original receiver again with the Tiger model modified to match the Churchill but it wasn't successful. Either the receiver has a glitch or the tiger model on the transmitter has an unexpected variable I cannot find. I will delete the old Tiger model and start afresh for the Churchill and hope the receiver is ok. Thanks again for you assistance.
Now I have the Tiger back together and ready for the open day.

Regards
Gary

Tiger is happy again..