TPOD Locking

Hi all,

First, let me just say that I’ve been debating whether or not to buy the JF17 for a while but I did last night just for the hell of it, and oh boy am I impressed.

I genuinely cannot believe that an early access product has been released in the states with this many complete features/toys. Granted, there may be a few bugs and things that are still in flight but overall, I’m very happy with my purchase and the state of the aircraft! Thank you Deka!!

I do have a question however. When I’m using the TPOD I find that the lock/focal point keeps moving around and can’t lock onto an interested target. Even after pressing the TDC lock, the focal point of the TPOD keeps moving.

Any ideas how to make it lock and stop moving?

Thanks!

make sure you're in air to ground master mode

Hi all,

 

First, let me just say that I’ve been debating whether or not to buy the JF17 for a while but I did last night just for the hell of it, and oh boy am I impressed.

 

I genuinely cannot believe that an early access product has been released in the states with this many complete features/toys. Granted, there may be a few bugs and things that are still in flight but overall, I’m very happy with my purchase and the state of the aircraft! Thank you Deka!!

 

I do have a question however. When I’m using the TPOD I find that the lock/focal point keeps moving around and can’t lock onto an interested target. Even after pressing the TDC lock, the focal point of the TPOD keeps moving.

 

Any ideas how to make it lock and stop moving?

 

Thanks!

You cant ground stabilize the TPOD if you are more then 20NM out. Make sure you are within 20NM on the target you want to lock. I guess thats the problem..

[someone enlighten me, if the TPOD can't ground stabilize beyond laser range how come it can perfectly stabilize from any distance when slaved to SPI from radar or pre planned point? I'm a bit confused:huh:

[someone enlighten me, if the TPOD can't ground stabilize beyond laser range how come it can perfectly stabilize from any distance when slaved to SPI from radar or pre planned point? I'm a bit confused:huh:

I believe the tpod uses INS to stabilize and track a point when it's out of range. There's a definite increase in stabilization lag when it's out of range vs when it's in range that's noticeable even when doing relatively minor movements with the aircraft.

[someone enlighten me, if the TPOD can't ground stabilize beyond laser range how come it can perfectly stabilize from any distance when slaved to SPI from radar or pre planned point? I'm a bit confused:huh:

your airplane has gps/ins and it's computer can calculate it's location in 3d space and it's vector of movement (using accelerometers, measuring angular velocity with gyros, it can measure air speed etc), it can also calculate the location of a waypoint in 3d space, relative to own position (necessary for navigation cues etc) and/or provide an angle to the tgp to point at

My point is: why doesn't the TPOD stabilize like a simple gyro, you know keep pointing at a certain direction. No need for fancy stuff ins/gps/rangefinder/calculation etc. Just stabilize, not track or designate.

it does, go to a2g master mode, then slew it to some direction (say 10 degrees lower than boresight) and it'll remain pointing to that direction (and you'll be able to see the ground zooming past you in the tgp view)

if you're asking why doesn't it continuously change angles so that it can follow what you slewed it at initially, then it's because there's something missing from being able to specify a point in 3d space: distance. You have a vector to a desired point, but the computer doesn't know how far along that axis the point you want to track is, so it can't calculate how fast it needs to rotate the tgp gimbal in order to follow it. If you're in a car that's moving at 50mph and you're looking at something on the side half a mile away, you'll be moving your eyes much faster than if you're looking at something that's initially in the same vector but 5 miles away. The computer in this case doesn't know how far the object you want to track is, so it can't follow it (basically it's focused at a point at infinity, as it can't laze&range)

Doesn’t it say “INS TRACK” when this happens? It’s really cool because it seems to jitter like crazy like it’s actually limited by the angular resolution of the INS data coming through the pylon and how fast the motors work. Gonna try it again and see if it slows down focus time also

One thing to keep in mind limiting it’s ability in DCS is that DCS has no contrast lock but a “center-of-a-living-unit-lock”

it does, go to a2g master mode, then slew it to some direction (say 10 degrees lower than boresight) and it'll remain pointing to that direction (and you'll be able to see the ground zooming past you in the tgp view)

 

 

 

if you're asking why doesn't it continuously change angles so that it can follow what you slewed it at initially, then it's because there's something missing from being able to specify a point in 3d space: distance. You have a vector to a desired point, but the computer doesn't know how far along that axis the point you want to track is, so it can't calculate how fast it needs to rotate the tgp gimbal in order to follow it. If you're in a car that's moving at 50mph and you're looking at something on the side half a mile away, you'll be moving your eyes much faster than if you're looking at something that's initially in the same vector but 5 miles away. The computer in this case doesn't know how far the object you want to track is, so it can't follow it (basically it's focused at a point at infinity, as it can't laze&range)

You're right in a way, but on most targeting systems since the 80's (70's really) there has been this thing called "contrast lock" I.e. the targeting system will try to stabilize to where you are looking by taking a picture of the image and then trying to keep your real time image aligned to that as best it can (periodically updating that). It would be really odd IMO if the JF-17 tpod lacked this ability, which it does seem to. Whereas the litening does seem to have it.

Harli it locks contrast as much as you can in any other TPOD in DCS. Hold down the lock button within 20nm and eventually a contrast gate will show up. Like my post above, nothing in DCS does contrast but auto locking living units. I was just meaning I don’t think it’s possible above 20nm probably because of TPOD API “faking” contrast lock

Harli it locks contrast as much as you can in any other TPOD in DCS. Hold down the lock button within 20nm and eventually a contrast gate will show up. Like my post above, nothing in DCS does contrast but auto locking living units. I was just meaning I don’t think it’s possible above 20nm probably because of TPOD API “faking” contrast lock

Likely true. I recall Zeus saying something about this forever ago with the harrier DMT and moving targets. But really it should be able to contrast lock terrain at really far distances is what I was alluding to. point it at Mt elbrus from 100mi it should be able to keep pointing at it. Its not the same as target contrast lock, but the same principle.

Does that mean that the ability of other DCS Tpods to ground stabilize at >20nm is not realistic?

It's probably realistic in terms of final outcome, but less so in how it is actually achieved in terms of image and position processing. You generally should be able to ground stabilise at those ranges — probably even with the WMD7 — but the way the game currently makes it happen is pretty cheat:y and it isn't really stabilised relative to the right kind of input.

Glacier;4182344']Does that mean that the ability of other DCS Tpods to ground stabilize at >20nm is not realistic?

Its likely very not realistic that they can generate JDAM accurate TOO coordinates at those ranges.

But being able to stabilize a ground track at longer range probably so, but things like haze/atmospherics jitter etc aren't really modeled in DCS either. Getting a high quality image from long distance from a moving platform, with all the vibration and jitter involved is "challenging". Pointing a laser with high accuracy also has the same issues.

People like to use TPOD's because they make life (very) easy though.

Maybe PAF didn’t like WMD-7 range either:)

https://quwa.org/2018/07/23/aselsan-confirms-aselpod-integration-on-pakistani-jf-17/

It'll also be interesting to see much of an issue it is if/when ground targets start appearing in any meaningful way on the ground radar…

Maybe PAF didn’t like WMD-7 range either:)

 

https://quwa.org/2018/07/23/aselsan-confirms-aselpod-integration-on-pakistani-jf-17/

Yeah interesting comments there.

The whole stable tracking issue being entirely separate from a coordinate generation issue of course.