Servo Operation

[Trailbiker]

Thanks, Michael. Mine definitely rotates more than 90 degrees, and so did the mini servos I was using. This is why I seem to have been having problems. I think Tankbear aka Ian , said that you could NOT change the rotation on the IBU, but have to double check that. Perhaps the way around this is to change the time interval again, on the MSD card. If, for instance, I was to make the trigger feed to the servo really short, then it would only complete a partial rotation, before the power was cut and it started its return phase. Correct me if I'm wrong on that assumption.
Thanks for all your help, Richard

[blimp]

Hello Trailbiker , I inverted my recoil servo - by the settings are on the SD card , i.e. to reverse it delete - TRUE and insert FALSE (upper case )

[Tankbear]

Hi Richard

You cannot change the travel distance of servo with the ibu2 but can the direction of rotation.

For modern tanks your better off with quick times something like 200-400 milliseconds in both directions works good.

Ian

[MichaelC]

Richard,

Based on Ian's comment you can just play with the timing on the servo by itself until you get the right amount of recoil angle then you can try fitting it. I am not too sure how much angle you can get out of the BB so you should probably play it it a bit with everything unhitch. I can't remember if there is any more travel left on my set--up.

Michael.

[Tankbear]

Richard,

Based on Ian's comment you can just play with the timing on the servo by itself until you get the right amount of recoil angle then you can try fitting it. I am not too sure how much angle you can get out of the BB so you should probably play it it a bit with everything unhitch. I can't remember if there is any more travel left on my set--up.

Michael.

I’m not certain if changing the times will effect the recoil angle, because the time is how quickly the servo will turn from min to max range. I guess technically there is a limit to how fast the servo can move its arm and barrel and if you set a shorter time than that the servo won’t have time to travel the full distance. But for ease of understanding expect the servo to rotate full distance in all instances.

Richard, after a couple of years of similar issues myself some one showed me a servo tester (£5-£10) This basically plugs into a 6v battery and controls the servo makes installation testing a lot easier.

Ian.

[Trailbiker]

Thanks for all the replies regarding this. Have been having a play this afternoon and set the recoil time to 250 milliseconds both ways. The servo still rotated more than 90 degrees, and I measured it at something like 35mm, which is still way too far. I can't understand why Michaels only travels a small amount, as it's the same servo, although he's using a Clarke board. Perhaps that's the reason.

Ian, I've sussed out that the last command is the servo direction and you just reverse the TRUE/FALSE to swap it around, but what is the first command, which says RecoilTimeDigital = 500 ?
And, should I make sure that the actuation time is always the same both ways ?
That servo tester sounds like a good idea. It's a bit of a pain having to connect the battery to the IBU and switch everything on, plug the servo in and then test how it works, every time.
The only way I can see to make this work, at the moment, is to put a really short arm on the servo. But that means it will have to line up precisely otherwise it'll be pulling at the wrong angle.
Richard

[MichaelC]

Richard,

IBU/Clark has to program the servo to do the recoil motion so it is not the servo setting that is the issue here. I am somewhat curious now as to how do other IBU users to their recoil ? If there are using the existing HL BB/recoil as a frame and the barrels from the HL, there is just not enough room to recoil as much as that.

The other option is to create a dead space on the linkage arm, i.e. it is loosely mounted the barrel end so that when the recoil start the motion, it will take up some slack before actually pushing/pulling the barrel. The only issue is that the barrel will now be somewhat loose in the mantlet because of the dead space/slack.

Also you can try mounting the servo further away instead of next to the BB mount. That will take up some slacks as well.

Do post some pictures Richard. I am somewhat intrigue by this as I know as some point I will acquire an IBU board at least to just play with it to see the difference.

Michael.

[Trailbiker]

I'll try and sort some photos tomorrow, Michael. The problem is that there isn't any room to put the servo anywhere else. On the side or underneath are the only places it can go. The side is limited by the pivot point at one end and the elevation motor/ramp at the other end. The small servos seem to fit better, and I was surprised as to how big the HS-311's were when they turned up. It was hard to tell how big they are in your picture, they look smaller.
Richard

[Tankbear]

Ian, I've sussed out that the last command is the servo direction and you just reverse the TRUE/FALSE to swap it around, but what is the first command, which says RecoilTimeDigital = 500 ?

This is the timing if your using a tamiya recoil unit, so you can ignore

And, should I make sure that the actuation time is always the same both ways ?

No don't have to and it's down to your preference. WW2 tanks tend to have a fast fire back and slow return, modern tanks are a quick back and return but it's what ever you want to suit your tank.

Ian.

[Trailbiker]

After more faffing about today, finally managed to get my Leopard 2A6 recoil to work properly.