StickTiltXY: Fix too high maximum tilt problem

[MaEtUgR]

Solved Problem

Reported by @alistair-blueflite when MPC_MAN_TILT_MAX is set to close to or 90° the accelerations go insane and I even had it that the stick input reverses direction at 90°.

Fixes #22714

Solution

• Consider 1° - 70° the recommended useful range. This corresponds to a 3:1 thrust-to-weight ratio.
• If the pilot sets MPC_MAN_TILT_MAX higher, guard against the calculations leading to a hardly steerable drone.
  Note: In stabilized mode MPC_MAN_TILT_MAX can be up to 180° and the controller will track it.
• Add unit tests.

Changelog Entry

Fix: Limit maximum tilt in Altitude mode such that close to 90° configuration doesn't cause issues

Alternatives

Having a multicopter tilt to 90° and expect it to hold altitude doesn't make sense, see also this comment: #22714 (comment)

Test coverage

• I did simulation tests to reproduce the issue and to verify it's solved.
• I added a unit test to make sure the case stays predictable.

Context

What do you think @alistair-blueflite?

[alistair-blueflite]

I think that looks good. If the pilot wanted more tilt in stabilized he can do that, while altitude doesn't do anything crazy.