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Besiege Notes on Entry Stabilisation (Broken Beyond Space DLC)

There are 3 types of celestial body in the Broken Beyond DLC:

1. static planet
2. static planet with ring
3. physical body (moon)
I'm interested in automatic landing. As I built and played with my spaceship logics, I found these problems:

The Ring Gravity:

At first I built my ship to align with gravity. The anglometer now has gravity mode, with them I can make my ship align with the gravity field. It works well with static and moving bodies without rings, but the ring will mess with the gravity direction. The machine will try to hover on the ring when it flies past, but since the planets are so small, there isn't time for the machine to right itself against the planet's gravity, then it ends with a crash.
The solution is to switch to velocity-mode anglometers. With it the machine will align with its trajectory. Using another two velocity-mode anglometers chained to a directional speedometer, it can activate braking to fall at a certain speed when the machine is aligned (say pitch and roll within +-15°). How this fixes the ring gravity problem, is that it reads the momentum of the machine, and it is in a sense the player's intention. Just aim roughly at the target planet, even in orbit, it'd do the job to slow down and land.

The Moon with Physics:

However, velocity-mode anglometers won't work on the moon. It is moving, so the approaching velocity should be the relative velocity, not absolute velocity that the anglometers read. It is true for the velocity's angle on anglometers, and it is also true for the speed read by speedometers. The braking automated by speedometer would be too strong when trying to land the tail side of the moon, and too weak for the head side; the speedometer auto entry brake will keep the machine from landing the tail side, and let the machine crash into the head side.
The alignment can be done by switching to gravity-mode anglometers in this case, but for the braking problem I haven't thought of a solution.

Gravity-align Entry:

When a machine approaches the planet with gravity-mode anglometer stabilisation, it's pointing thrust direction towards the planet. That will be a problem because the tangent speed about the planet isn't reduced during braking, the machine will glide around the planet just a bit, or orbiting, or at worst escape and miss. It will need some thrusters linked to directional speedometers to kill the tangent speed.
Trajectory alignment doesn't have this problem. The machine can aim at the outer atmosphere of the planet and approach in high speed, the brake will handle it well, as it is aligned with velocity and directly killing the speed. And it is the basic knowledge of orbiting physics: reducing tangent speed will bring things down from orbit.

For my auto landing logic, I'm going to have both gravity and velocity alignment to choose from accordingly to the type of target body. Now only the braking of moon landing isn't solved.

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