APKWS II missing IOG?

Machinery of War Discussion Aircraft
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From “Dave Harrold, product line director, precision guidance solutions, BAE Systems.”

"“With these semi-active seekers, the optics are looking for the energy that is bouncing back off the target that the laser designation has put on. They are receiving the laser energy that is coming back from the target; both the information from those optics along with the information from the on-board IMU [Inertial Measurement Unit] figure out where the target is and then navigate toward that target,” he added. "

Is this anything or does a statement from the company that makes the weapon not count for bug reports?

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likely the inertial measurement unit is only to figure out where the missile currently is, not where the target would be if lock on the target is lost

inertial measurement unit =/= inertial guidance

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it’s on heli, not rockets

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They are receiving the laser energy that is coming back from the target; both the information from those optics along with the information from the on-board IMU [Inertial Measurement Unit] figure out where the target is and then navigate toward that target,

The heli doesn’t transmit IMU data via the laser. It’s an IMU on the rocket to autopilot to the target. See picture

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I don’t believe this would constitute an IOG function as it works in-game.

In-game it basically gives weapons a GPS guidance function which is not what this IMU is doing. As I understand it the IMU just determines the rockets current state in relation to the laser reflection and then transmits that to the autopilot to control the actuators.

This is a pretty good slide for any performance bug reports though.

Spoiler

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And I’m fairly certain at least the off-axis capabilities of the weapon are inaccurate currently.

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Inertial guidance,… not GPS.

GPS guidance suppose to have a DL with satelites

Inertial guidance is given by internal calculation of position.

GNSS / GPS are guidances system in game.

IMU only allow for a precise guidance, by knowing exactly how the rocket is currently flying → it’s neither GNSS/GPS or IOG.

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All GPS is in-game is just an INS/IOG with 0 drift.

However giving a AGM the IOG trait allows it to “self anoint” prior to enabling the laser, just if it is only IOG and not GNSS, it’s drift will be large enough it will miss virtually every time.

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thats not true for a while now.

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when i take AASM-250 (SBU-38) - only GPS/GNSS (same thing) guidance - and drops it with an offset to the target, it calibrates it trajectory to end-up flying towards it.

so it drifts itself towards the target.

IOG simply follow the last interception point given by the system.

this means for exemple, that the IOG on AIM-7P (early F-18C’s) will continue to steer towards the last interception point calculated, but will not track it’s target anymore.

same goes for Laser+IOG systems, if Laser is unable to provide a point anymore (say that you turned away or smoke is used) then the bomb will go to the last point given
this is possible with several AGM/GBU in game.

YEet we still agree that IMU is not an IOG, neither it is a GNSS

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That is true. The CEP deviation is not drift.

Yes, with an INS drift. The difference is GNSS+IOG vs just IOG, the first actually has no drift value while second one does.

You can fire both without ever turning on your laser, but only the +GNSS munition is ever going to hit because there is too much drift just the IOG.

This is the same thing, genius. One just has drift on the INS system.

You are using terminology incorrectly here. Are you being deliberately stupid or pathetically incompetent.

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the missile knows where it is because it knows where it isn’t
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