Oolite Bulletins

I am concerned about docking computer reliability in ships larger than the Cobra3.

Having just installed my first Oolite DC into my python, I tried the docking sequence.
It took a looong time to line up (It could be sped up a little). That aside, I was killed when my ship entered the dockingslit. As far as I could see, not due to colliding with an exiting ship.

A possible solution could be to cheat and make the ship indestructable, or better yet: a 'ghost', during the final stage of docking.


(external view of your ship would also be greatly appreciated )

Arexack_Heretic wrote:

(external view of your ship would also be greatly appreciated )

Work is proceeding...

I get the feeling that docking shouldn't really be AI at all.

Coming back to real life, autoland on planes doesn't work by AI. There are a set of ground transmitters (localiser and glideslope) that transmit a horizontal and vertical guidance radio beam. Simple electronics on the aircraft keep the plane centred up on the GS and loc. If the plane 'sees' it's drifting down, it adds a little up elevator until the GS starts to move closer again, same with the loc. In the old days, this was done using analogue components such as phase discriminators.

Maybe the space stations should just transmit a 'virtual beam' on the extended centreline of the docking port. Ships would just use simple logic to tell whether they are above or below or left or right of the beam, and just home in on the beam at a 'final approach fix' (say, about halfway between the beacon and the port), then just follow the beam. The only AI that would be needed would be to rotate the ship and line up with the docking port. The AI could conceivably dock accurately at full speed this way - fly full speed towards the final approach fix, slow for the turn, get on the beam, then fly full speed at the docking port. It'd save a lot of time

winston wrote:

Maybe the space stations should just transmit a 'virtual beam' on the extended centreline of the docking port. Ships would just use simple logic to tell whether they are above or below or left or right of the beam, and just home in on the beam at a 'final approach fix' (say, about halfway between the beacon and the port), then just follow the beam. The only AI that would be needed would be to rotate the ship and line up with the docking port. The AI could conceivably dock accurately at full speed this way - fly full speed towards the final approach fix, slow for the turn, get on the beam, then fly full speed at the docking port. It'd save a lot of time

Hmm, would this help with using the DC with Behemoths, I wonder? The trick would be measuring L/R, U/D and Fore/Aft... Otherwise you may end up attempting to enter the station from the back, which as well as being open to scatalogical humour is probably bad for your health.

Given that airplanes have had instrument landing systems for well over 30 years that can land all sorts of planes reliably without the pilot interfering in all but extreme weather conditions it really is quite incredulous that a space ship should have trouble docking using its docking computer. It should be a fast, efficient process.

Passenger planes can, these days, fly their entire route on autopilot, with the pilot essentially only needed for taxiing and telling the autopilot where to go. Pilots tend to fly themselves because letting the autopilot do everything is boring, and because they need the practice in case the autopilot fails.

This is in part why I don't bother with manual docking or the long docking computer sequence - I just press shift-D and dock instantly.

As far as i can remember docking computers used to kill even on the old Elite (i.e. amiga). I remember mine trying to dock from the opposite side of the station resulting in a nice spillage of platinum and gemstones...

I've not mentioned this before, but I can only get Shift-D to actually dock,
C and shift C (when targeted) just acts like pausing the game, is this just on PC oolite?

The shift-c, c-docking works fine for me with the NIC 1 build.

You need to be quite close to the station to enable the initiation of the sequence though;
at ranges further than near collision with station, the autopilot just goes into 'altitude controll'.

Yay...... it works on the Nic build 2 as well, I was not close enough. Shift D obviously works from a longer range.

On classic elite IIRC the autodocking worked from even a much longer range ie as soon as the space compass picked up the space station, very useful approaching an anarchy system when your arse is being kicked bigtime by pirates or thargoids and your shields and energy banks are complaining loudly. Now of course you can use witchdrive injectors, on the shorter hops, but on the long ones well..........put on your seatbelt!!!

In classic Elite the docking computer would only ever work when you were inside the station's safety zone, and the S had popped up on your console. This happens quite a while after the space compass picks up the station IIRC. Until then it did nothing.

Old Elite versions would indeed kill you with the docking computer, especially by crashing into the back of the station. (I put that down to Breadbin & Bell not spending quite enough time to work out a decent docking algorithm - I suspect the docking computer was a bit of an afterthought.) The exception to this was the Electron version, which didn't have the full docking sequence programmed into it, just fast-docking. That's another reason why I don't have patience with the full sequence - I started out with the Electron version.

stevesims wrote:

Passenger planes can, these days, fly their entire route on autopilot, with the pilot essentially only needed for taxiing and telling the autopilot where to go. Pilots tend to fly themselves because letting the autopilot do everything is boring, and because they need the practice in case the autopilot fails.

Autopilots (generally) have worked on the 'follow the beam' principle (for horizontal guidance - there's also gyro input so it knows which way is up and the rate of turn that is happening). Nowadays, you've also got INS and GPS for the auto pilots on large aircraft. Autopilots on light aircraft can generally couple to GPS as well as the old VOR receiver. But even with GPS, it's essentially following the beam - there are interfaces so even ancient Piper Autocontrol II autopilots (which is really pushing the definition of autopilot, it's a mess of analogue electronics such as phase discriminators dumbly driving servos) can be guided by GPS (the GPS just signals the autopilot in the same way a VOR receiver would signal the autopilot).

En-route, airline pilots tend to just use the autopilot - jets are tricky and annoying to hand-fly during cruise. ATC instructions and the like will generally be complied with by twiddling the heading, speed or altitude knobs on the autopilot. However, they will hand fly all the approaches they can, a typical long haul jet pilot might only get to land for real twice a month and would have a hard time staying current unless they hand-flew every approach they could. They'll still use the autothrottles though. Airspeed is critical when flying a jet - you can get away with being a bit sloppy in a light single engine aircraft, but getting too slow in a jet tends to have serious consequences!

winston wrote:

...They'll still use the autothrottles though. Airspeed is critical when flying a jet - you can get away with being a bit sloppy in a light single engine aircraft, but getting too slow in a jet tends to have serious consequences!

Well, only if you ph34r gravity that is.

Well, not so much gravity as the ground coming up to smite thee! Get slow in a light plane and note the sink rate going up? Push in the throttle and you get instant thrust. Get slow in an airliner and note the sink rate going up? Push in the throttles and wait...and wait... and wait [...] and wait and eventually the engines will spool up but by then you might have met terra firma by the time they do! (Modern turbines are a lot better than the old ones - but remember that new Airbus they pranged in France at that air display when he got too low and slow? The engines were only just providing the requested power once the tail of the plane was being dragged through the trees, sealing his fate).