The 100km Rendezvous Challenge

[pebble_garden]

=================================

LEADERBOARDS

TIME TO RENDEZVOUS (TTR)

Name______________TTR____TTD

Jasonbail..................4:34......n/a <

Aphobius..................4:55.....5:00 <

YarTheBug................5:51.....6:47

pebble_garden...........6:55.....8:45 <

TIME TO DOCK (TTD)

Name______________TTR____TTD

Aphobius..................4:55......5:00 <

Jasonbail..................5:39......5:42 <

YarTheBug................5:51.....6:47

pebble_garden...........6:55.....8:45 <

=================================

I must say I'm impressed by the entries. That's some damned fine flying.

=================================

Fly the provided Garuda spacecraft to a rendezvous with a station in a 100km orbit, in as little time as possible. You must get within 20 meters and under 0.5m/sec relative velocity. Extra credit for docking!

Slight Modification: Jasonbail rightfully points out that getting a good TTR is often detrimental to a good TTD. So I'm splitting out the two victory conditions. Whichever you can do faster, go for it.

The 100km Rendezvous Challenge

That video shows my best attempt so far, with a rendezvous at 9:10 MET and docking at 11:46 or so. For more information on this kind of direct intercept maneuver, please watch my Phoenix Project Part 3 video.

You can download the saved game (with instructions) here.

I'd love to see your screenshots of the MET clock when you reach the station.

Action Group Keybindings:

Garuda Orbiter

1 - Toggle docking shield open/closed

2 - Toggle docking lights

3 - Toggle solar panels deployed/stowed

4 - Toggle orbiter engine and gimbal

Station

6 - Toggle top lights

7 - Toggle lower lights

8 - Toggle solar panels deployed/stowed

9 - Toggle engine and gimbal

In the .zip file I've added two additional savegames (*.sfs files). Just rename the one you want as persistent.sfs and reload the game.

Edited August 22, 2013 by pebble_garden
Split out the TTR and TTD leaderboards

[YarTheBug]

06:39 to rendezvous, 08:19 to dock (took about 5 sec to lock in).

Javascript is disabled. View full album

Cheers to a great Video!! Sorry if I scorched your solar panels a bit

[pebble_garden]

Amazing! How did you manage such a good time? My guess is you launched when the station was closer than 400km and your approach was closer to vertical than circular.

(edit)

I had to try to beat (or at least match) that time, so here's my latest attempt. Sadly I only managed a 7:57 TTR (Time To Rendezvous) and 9:45 TTD (Dock).

Edited August 17, 2013 by pebble_garden

[pebble_garden]

Hah! I'm getting better. Results of my third attempt:

TTR 6:55 MET

TTD 8:35 MET

That was, I must say, very stressful. My hands were shaking as I lined up for the final thrust into the docking port.

Piccies!

I have a video if anyone is interested. Just let me know and I'll upload it.

Edited August 17, 2013 by pebble_garden

[Saberus]

I have a video if anyone is interested. Just let me know and I'll upload it.

::Raises hand:: interested. Still working on getting it. I'm still either shooting past the station, or smashing it to bits.

[pebble_garden]

::Raises hand:: interested. Still working on getting it. I'm still either shooting past the station, or smashing it to bits.

Average those two outcomes and you come up with a rendezvous and dock! Anyway, I can't wait to see you succeed. Keep trying!

I'm rendering the video now. Should be ready in a few min.

[pebble_garden]

of my third attempt at the challenge.

[Saberus]

Average those two outcomes and you come up with a rendezvous and dock! Anyway, I can't wait to see you succeed. Keep trying!

I'm rendering the video now. Should be ready in a few min.

Averaging my speeds between the two I still come screaming in at 39.1 m/s... I need to try a different tack. Maybe actually stepping back and completing a docking maneuver first, before going for some speed record. Learn to crawl before running a marathon.

[YarTheBug]

@ Peb: Thanks for the shout out! I only did a few things different from your first vid:

1. Beer: it kept my hands from shaking.

2. Takeoff: Throttle to full until overheat was at the "!" ("t" on your resolution)

3. MET: on close approach I kept it around 10s, e.g. 500m/s @ 5km, 200 @ 2km

4. Docking: Throttle to close to the Alpha Station and send it spinning through the ether (had to switch over and straighten it).

Great time, thought you had me! I wouldn't know the PebbleGarden method of rendezvous unless you'd shown us with the Phoenix.

@ Saberus: Just post what you've got. I like watching/reading what others do, and almost always learn something from it.

(edit: and pics of explosions are always welcome)

- Yar

[pebble_garden]

@ Yar:

Beer? I shall have to add that to my checklist.

PebbleGarden Rendezvous Method? Hahaha Now *I'm* famous. Still, I'm kind of amazed how far we've been able to push it.

@ Saberus: Yeah, I second Yar's motion. I'd love to see or hear how you did. You say you're striking the station at 30m/sec....that's an amazing accomplishment in itself, and you're *this* close to success too!

[Saberus]

@ Yar:

Beer? I shall have to add that to my checklist.

PebbleGarden Rendezvous Method? Hahaha Now *I'm* famous. Still, I'm kind of amazed how far we've been able to push it.

@ Saberus: Yeah, I second Yar's motion. I'd love to see or hear how you did. You say you're striking the station at 30m/sec....that's an amazing accomplishment in itself, and you're *this* close to success too!

Well, that's 30m/s that my craft is going relative to Kerbin. I'm going straight up, not trying to match orbit until after 55km over the surface. So I'm smacking into the station while it has orbital velocity.... and I'm nowhere near that. So my craft is acting more like an anti-satellite missile than anything. My swear jar is nearly overflowing because I'm finding myself burning full-throttle away from the station in a futile attempt to match speed with nowhere near enough space to do so.

I feel the best analogy is that I am doing the orbital equivalent of avoiding the onramp to a highway by cutting through the median, turning onto the roadway, then trying to accelerate to match the speed of traffic. Except traffic is 18-wheelers cruising at 60mph, and I'm in a '53 Iso Isetta.

I just need to step back and stop trying to be a missile.

Edit: Somehow that 30m/s is sticking in my head, but I'm wracking my brain that it doesn't sound right. I'm at work still, I won't be able to verify until I get home. I know my two attempts resulted in one fly by while being 12ish kilometers away and out into deeper space in a pointy, narrow parabolic trajectory, and the other time I'm burning like mad to slow down and just smash through Alpha Station's battery/ASAS...

Edited August 17, 2013 by Saberus
Something's not right....

[YarTheBug]

Quote(Saberus): "So I'm smacking into the station while it has orbital velocity.... and I'm nowhere near that. So my craft is acting more like an anti-satellite missile."

(((0.0))) now THAT is a challenge! I am officially jealous, and you MUST post a screenshot.

Peb's Pheonix project is a good, conservative baseline. We're just seeing who can do that fastest here.

[Tw1]

= So I'm smacking into the station while it has orbital velocity.... and I'm nowhere near that. So my craft is acting more like an anti-satellite missile than anything.

1. Replace station with a mass relay.

2. ??????

3. Profit.

[pebble_garden]

1. Replace station with a mass relay.

2. ??????

3. Profit.

You know, my coworker actually worked on Mass Effect. He's a hell of a vfx artist. I've learned a lot from him. Totally off-topic, I know, but I'm the OP so it's okay.

[pebble_garden]

I just need to step back and stop trying to be a missile.

The best advice I can give you is to follow my flight profile, and see where that gets you. Here is the system I use:

1. Take off when the station is 400km away (selected as Target). Throttle is set to 2 ticks above 2/3 power.

2. Jettison the external tanks as soon as they are empty.

3. At 20km altitude, begin rotating to a 45 degree pitch angle along the 90 degree heading. Finish the turn before reaching 30km.

4. Jettison the second stage when it is empty. Go to full throttle and pitch over to about 27 degrees, still on the 90 degree heading.

5. Switch to map view, and watch apoapsis. Level off when the AP reaches 100km.

6. By now you should be in Target mode on the nav ball; it switches when you are within a certain range.

7. Notice where your retrograde marker is (green circle with three radial lines). Try to position your navball's center point so it's the mirror opposite of the station, relative to your retrograde marker. This will 'push' your velocity marker onto the station's.

8. Watch your closure speed (in m/sec) with the station, try to keep it 30-20 times your distance in km to the station. Thus, if you are 5km from the station, your closure speed should be around 100-150m/sec. Faster = braver, slower = safer. A 10x or 5x closure rate won't win the challenge, but it may get you there safely, which is itself an accomplishment.

9. Jettison the third stage when it's empty.

10. Continue to reduce your speed to stay on the 20x-30x approach curve, while adjusting your thrust angle to push your velocity vector icon onto the station's.

11. Trust your instruments!

12. Within 50m of the station, trust your Mk1 eyebals!

I know that's a lot to handle (which is why it's a challenge), but steps 1-5 are really easy, and the later steps just take practice. But by the end of step 5, you are no longer a missle. You're now a piloted orbiter. So give it a shot!

Edited August 18, 2013 by pebble_garden

[Jasonbail]

Managed a sub 6 minute rendezvous. You can be the judge of when because for a second I had to switch vessels to correct a spin for slamming into it which pisses me off because I could have done much better if I didn't think I would get lucking just raming into it for a dock. The correction dock takes place at 6:12 which is pretty good still.

Edited August 18, 2013 by Jasonbail

[pebble_garden]

in my opinion, if the station doesn't explode, you're fine.

Six minutes? Holy cow. I wanna see the picture of that.

[YarTheBug]

My final Attempt:

Javascript is disabled. View full album

Sadly, I'm at 5:51 and 6:47 (I hit F1 once/sec. The next screenshot after 6:46 shows me docked with the station MET)

I must concede victory to a bolder Jason(bail) at 5:44 and 6:12. Maybe it's the Red Bull tonight instead of beer, but my hands were shaking too.

Cheers!

- Yar

[pebble_garden]

Let's think about this for a minute. Under 6 minutes for a rendezvous at 100km, and a dock at under 7 minutes? I am well and truly amazed.

[Aphobius]

I present to you:

[pebble_garden]

I'm...well...speechless. That is some godly flying. I call that 5:01 TTR, 5:57 TTD.

[YarTheBug]

I think I just watched MechJeb turn green with envy.

Cheers, mate!

[Aphobius]

Thank you for your appreciation.

It was only my second attempt (first one was to get an idea about the distances/burn times), I didn't wanted to make it unfun for the potential competition.

So I hope more people will try this and eventually even beat my times, so I have a reason to do it a few more times.

[HeadHunter67]

PebbleGarden Rendezvous Method? Hahaha Now *I'm* famous. Still' date=' I'm kind of amazed how far we've been able to push it.[/quote']

I would never have even thought it possible if you hadn't shown how it's done. You make it look easy... actually, you just make it easy. If a rookie pilot like me can do a direct launch-to-rendezvous on his second try, anyone can learn how. Mind you, I'm nowhere near good enough to beat those times yet.

[Jasonbail]

I have comlpleted a run that beats aphobius TTD at 5:42 but with a 5:17 TTR.

What I've noticed is that if I go for a run with a better TTR it negatively effects my TTD time because I slow down way earlier than I would normally. And this effect works inversely, if you go for a fast dock and fly past the 20M mark at higher than .5M/S

I suggest that the ranks for TTD and TTR be separated as they are not going to be proportional as the best times become more refined.

Edited August 19, 2013 by Jasonbail