Tutorial How to write an Axis Assignments (Math) Plugin for SimTools 2.0 - API documentation

I don't know if this is the right place...
What I would like to do is the following:
1. compare surge and sway to the current axis pitch and roll positions (so the combined output to the platform axis)
2. Depending on the difference, calculate a movement acceleration which is under the discernable threshold
3. output this as motion to pitch and roll.

So I need an interface where the user tells me what axis are pitch and roll, and then I deliver an input to these axis.

It will function like a washout input that always keeps moving to the tilt position that is dictated by current surge and sway. It limits the speed so the user doesn't feel the platform accelerations caused by this movement.

What I don't find in the example is where to get the current output of Simtools.

What I would need to code my feature is the current position, since I want to move the platform to a defined absolute position, not just a relative position.

What I am trying to implement is an addition to motion cueing. Motion cueing by itself is fine, that's all relative. But you get to absolute positions when you want to simulate long constant accelerations in surge and sway by tilting the platform.

The platform needs to move slowly but as swift as possible below the discernable threshold towards the position that corresponds with current surge and sway. If the user feels this movement, it becomes a false roll cue and we don't want that.

This also acts as a very controlled washout that keeps bringing the platform to neutral (acceleration corrected) so the motion cues themselves don't need another washout effect. The result will be additive to the cues, but by basing these on the distance from the desired neutral position, so it will keep trying to reach the neutral postion.

Right now, washout is connected to motion cues. That is not really correct. If a motion cue by coincidence moves the platform back to neutral, we don't actually need washout. So the logic cue-washout, cue-washout is fundamentally flawed because it doesn't take the absolute position into account.

Washout should be based on the need to keep away from the physical limits of the platform to always keep room in all directions for cues. i.e. staying away from the limits means centering. And center is an absolute position.

Then, there is motion that does not need a washout, constant acceleration. Even with a 6DOF, you can't really do constant acceleration because you can only move a second or two in any direction. The only constant accelerations you can simulate is surge and sway by tilting the platform, making gravity feel like surge or sway. This is also a movement to an absolute position. You want to be a certain distance and a certain direction away from neutral so gravity is felt in certain direction.

Then there is the point that washout movement and gravity shifting shouldn't be felt as a cue. If they are faster then the rotational threshold our vestibular system can sense, it will be a false motion cue. A high pass filter doesn't cut it, especially on reversions where the high pass will also reverse very quickly. If you don't base the washout on the cue, but make it an independent motion, it can be better controlled to stay below the threshold.

Cueing is exploiting the insensitivity of our vestibular system in the sense that it will give it a nudge and then our brain assumes an ongoing motion that has just fallen below the threshold. If we then give it a cue that doesn't fit, the cue we wanted to give is basically cancelled prematurely.

So what I wanted to do (myself, this is neither criticism of your software nor feature creep), is to create a constant, ever present slow "magnetic" pull of the platform towards center. Or if surge or sway are present, to a corresponding offset center. With its own maximum acceleration, so that it moves the platform without the user feeling it. No longer would a fixed washout be tied to every cue, because centering is already being taken care of.