The Kerbin 1K Drag Race (needs Races! mod)

[Lisias]

55 minutes ago, Jacke said:

As I found out when I tried to improve mine, you don't just need a few MOAR BOOSTERS to truly increase the speed, you need like at least double to triple or even MOAR BOOSTERS.  Increase in the mass and drag can easily overwhelm any increase in thrust, even when you control the amount of solid or liquid propellants.  Cutting the mass and drag as well is another approach, but it's easy to makes the vehicle track worse and crash more often.

Yeah. Drag scales exponentially and inertia linearly so your thrust scales (more or less) logarithmically. Since this is a short run, inertia plays a bigger role than drag on the first hundred meters. I would had TweakScaled the tank to 1.25M if mods would be allowed, that would had saved me some drag and inertia.

Keeping the vessel on the ground is not hard - I choose a triple stack adapter exactly due this - the upper engine is slightly stronger than the lower ones, pushing the wheels into the ground. This stunt works for speeds up to 800 or 900  m/s, when then the wheels collapse. On higher speeds, you need winglets to keep your craft on the ground, but things became tricky - it's hard to trim the control surfaces to keep the vessel on the ground without smashing it on the ground as speed increases and the wheels get more stress due the increasing negative lift.

Edited March 29, 2019 by Lisias
tyop! Surprised?

[qzgy]

1 hour ago, Lisias said:

On higher speeds, you need winglets to keep your craft on the ground,

... No? On mine I only have the control surfaces on the back to act as air brakes at high speeds and for control. I think on mine I have the wheels in such a way so that its pointed a bit down so the thrust is pushing it into the ground, but I dont think I even have that. It's so low drag that it doesn't seem super affected by body lift or anything.

To the point about wheel stress, I don't like having to deal with it, so I use the airplane gear which are more resistant to spontaneous breakage.

2 hours ago, Jacke said:

Cutting the mass and drag as well is another approach, but it's easy to makes the vehicle track worse and crash more often.

Wheel friction settings ftw! and also a fin at the back.

[Lisias]

1 hour ago, qzgy said:

... No? On mine I only have the control surfaces on the back to act as air brakes at high speeds and for control. I think on mine I have the wheels in such a way so that its pointed a bit down so the thrust is pushing it into the ground, but I dont think I even have that. It's so low drag that it doesn't seem super affected by body lift or anything.

It's not sustainable. Try to run more than 10Km with your vessel and see for yourself.

On mine, I lowered a small bit the front wheels so the fuel tank could do some negative body lift, but this is not sustainable as the speed increases too much as it would over-stress the wheels sooner or later.

Not an issue on a Dragster that would accelerate for only 1.000 meters, but anything more than that you will smash your belly on the ground for sure.

 

1 hour ago, qzgy said:

Wheel friction settings ftw! and also a fin at the back.

You managed to get away with small fins due the craft's low mass. [Not quite, see below] I had to shove 5 on mine to keep that thingy running straight - and just took the hit for the drag. As the front wheels gets more traction than the rear ones due the pressure caused by the speed, the friction starts to be an issue and the tail starts to overtake the rest of the vehicle - so I would never reach that extra speed anyway.

Wheel friction would help me a bit, I think. But I had run out of time for playing and published what I got.  I think I could eliminate the center fin too (and so, save a little bit of drag) - but didn't had the time to test it.

— — — — POST EDIT — — — — 

I tried the Mark IV of yours. My observations appears to apply to it, the thingy started to "bank" up to 10° from left to right and back over the wheels, half the track it was running on only two wheels (rear and alternating one of the front ones), and ended up off track before the end of the runway. 

Due the huge count of parts, this can be a glitch on the physics due my machine being not par to yours, so I  tried to use Time Control to see if I improve things, but apparently it got worse.  Krakens attacked your vessel, it always explode when I revert to launch (and so, I cannot activate the Time Control before the wheels start to kick as rabbits).

Edited March 29, 2019 by Lisias
Post edit

[NBDesigns]

5 hours ago, Jacke said:

As I found out when I tried to improve mine, you don't just need a few MOAR BOOSTERS to truly increase the speed, you need like at least double to triple or even MOAR BOOSTERS.  Increase in the mass and drag can easily overwhelm any increase in thrust, even when you control the amount of solid or liquid propellants.  Cutting the mass and drag as well is another approach, but it's easy to makes the vehicle track worse and crash more often.

Yes @Jacke I found that taking 100 sepertrons had tons of weight, I chose to see what the weight of the vehicle was after reductions to the solid fuel amount. I was able to do a 2.8-3 second burn at twr of just over 25:1. After that additional rockets started to summon the kraken for me and I reverted immediately. 

[Triop]

Hi all, sorry I didn't finish the finals yesterday, I fell asleep . . .

Next up is the last contestant @sturmhauke and @qzgy's re-run.

TBC

[Triop]

RACE #8

sturmhauke - Sunday Driver

 

It went flying after the race so it's legit for me, parachutes worked fine using the abort as suggested. 03:44 3th place, nice.

Some of you are very close with timing....

1: HB Stratos - 02.84

2: Lisias - 03.38

3: sturmhauke - 03.44

4: NBDesign - 03.48

5: Ultimate Steve - 03:58

6: Jacke - 03.70

7: Gapone - 05.44

Next up is @qzgy re-run.

TBC

 

Edited March 30, 2019 by Triop

[Triop]

Interesting....

Very fast, but very unstable:

https://www.youtube.com/watch?v=hPHnoAI4tOU

After 2 minutes waiting on my slow pc . . .

I did manage to get 1 stable run :

https://www.youtube.com/watch?v=Zo65iW_iM7Q

But the Races! mod didn't time it, nevermind the Sunday Driver crashed after that run, I was flabbergasted and forgot to activate the chutes.

As you can see in this next screenshot, it's a 02.04 car.

This was @qzgy's first run:

https://www.youtube.com/watch?v=8prm-xo-jU0

It's the fastest car, but very unstable and the braking system isn't realy up for the task . . . .

What should I do ?

Should I put his first run on the scoreboard or should I DSQZGY ?

Help !

Edited March 30, 2019 by Triop

[NBDesigns]

@Triop I say keep the time, it’s a pretty kerbal way to achieve that speed. 

[Lisias]

Well, the rules said:

Quote

Challenge:

-Build a super fast car that can race 1000 meters on the runway and stop without exploding

And such it did.

So I agree with @NBDesigns, the first place it's his. His craft ended the run with more parts than mine!

how about a second contest with more demanding rules? This is fun! 

 

 

 

 

Edited March 30, 2019 by Lisias
Hit "Save" too soon.

[HB Stratos]

@Triop I´d say the craft needs a working braking system. I know I would be leading then, but killing kerbals is not really the way to do it and every other craft has a woking braking system

[qzgy]

2 hours ago, HB Stratos said:

@Triop I´d say the craft needs a working braking system. I know I would be leading then, but killing kerbals is not really the way to do it and every other craft has a woking braking system

Just gonna go on the record and say in my testing the braking system has worked. If you want me to make a video and see why I say that, I can go do that. 

It is a janky one, and not as effective as others, but it has worked. 

EDIT: Hmm..... this might be a version thing why it explodes at the end. Since I built and tested stuff in 1.3.0, I never really did test it in 1.6, and in between the two it seems the way it behaves has changed. Not 100% sure why though, but yeah.

Edited March 30, 2019 by qzgy

[HB Stratos]

by the way could I submit an improved version of my speedster?

[Deddly]

I like @qzgy's craft, but it seems to be just about to explode at the moment the video stops. I understand that he has got it working, but I think it's supposed to work within those three official runs, in which case, that seems to be a DQ, in my mind. I didn't submit any crafts so I'm unbiased, just giving an opinion

[Lisias]

4 hours ago, qzgy said:

EDIT: Hmm..... this might be a version thing why it explodes at the end. Since I built and tested stuff in 1.3.0, I never really did test it in 1.6, and in between the two it seems the way it behaves has changed. Not 100% sure why though, but yeah.

This caught my attention. It's somewhat unrelated to the Contest, but yet it worths to be mentioned.

There's a thingy called "FixedUpdate" on the C# side of the Add'Ons. This thingy is called about 50 times per second (20ms intervals), if I remember it correctly. This is the heartbeat of the simulation, anything that happens in less that this heartbeat is ignored, and anything that happens between such heartbeats is "rounded" to one of the heartbeats. This is also one of the reasons powerful machines appears to perform bad on KSP - the FixedUpdate is the Critical Path of the simulation - it goes bad, everything else is irrelevant.

Mangling with this, I realized that if you mangle with it, the game can run faster but physics gets brittle, or physics can run smoother but the game runs cranky.  You can mangle with it using Settings on the Main Menu, General, and using the slider called "Max Physics Delta-Time per Frame". Mine is 0.04 at this time, and @qzgy's craft is essentially a 4th July show on reload.

I will mangle a bit with this and get back to this post soon.

— — — POST EDIT — — — 

So I come to this.

I used 0.03 on the Max-* thingy (the lowest value possible), and boy, this vessel are now the best 4th July fireworks I ever watched on KSP.

Then I tried 1.12 (the max value on the slider), but the keyboard stop answering on the game.  Don't now if I found another bug, or if this is just a Kraken Food. In a way or another, I didn't bored to get into it and gave up.

In all situations, "Revert to Launch" summons the Kraken's Holy Rage on the vessel. 

So…. I tested it on 1.3.1 . Guess what? It worked fine. It stayed on the airstrip without my intervention, the thing just works and by its own. I think he got bitten by the new wheels module from 1.6.1 , by the way. Yeah, blame Unity on this.  

But Reverting to Launch still summons the Kraken's Holy Rage on it.  

So I stand by my opinion. @qzgy 's entry is as valid as mine. They followed the rules by the letter (I kind of twist it a little… hehehe) as @Triop didn't specify the KSP to be used. It can be seen as a loophole on the rules, but mine is also, so…  

P.S.: I used the Mark IV version, didn't bored to download the newest version to try it. I was trying to understand the physics differences, not to second guess the run so I gone for the more "problematic" version.

Edited March 30, 2019 by Lisias
Post edit

[swjr-swis]

How about an under 2 second run that stays on the runway and keeps Kraken away, kerbals alive, and parts unexploded?

Spoiler

722 m/s top speed, 1.25km in under 2 seconds. At a somewhat potato-friendlier 249 parts.

Craft file: https://kerbalx.com/swjr-swis/The-Egg-5b

Full album: https://imgur.com/a/DpI1ack

[Lisias]

1 hour ago, swjr-swis said:

How about an under 2 second run that stays on the runway and keeps Kraken away, kerbals alive, and parts unexploded?

What did you used as "wheels"? (damn! I didn't though on that… a wheelless car!)

[Triop]

Ok, things are not going very smooth here, but I see some people are very dedicated to break some records.

My suggestion is download and install the Races! mod yourself:

Then download and install the track:

https://www.dropbox.com/s/4cmf7t7yz8vooo1/RatRodDrag.krt?dl=0

Take a run, make a screenshot of your results and post it here.

I'm opening this up for everybody, but I'm not going to do the races myself no more.

I'll keep up the scoreboard.

@qzgy , @HB Stratos has a point, since his run was smooth without problems setting the fastest time, I can't put you up there (yet).

I don't want to start wars or be involved in one, so I suggest download the mod, do the run and send in the results.

Goodluck people.

Scoreboard:

1: HB Stratos - 02.84

2: Lisias - 03.38

3: sturmhauke - 03.44

4: NBDesign - 03.48

5: Ultimate Steve - 03:58

6: Jacke - 03.70

7: Gapone - 05.44

8: qzgy - fastest time, but not official, hope to see you back Q

 

Edited March 31, 2019 by Triop

[Lisias]

1 hour ago, Triop said:

Ok, things are not going very smooth here, but I see some people are very dedicated to break some records.

Just some disagreements on how to interpret things. It's healthy, it's what drive us ahead and make us do better things in the future.  

I like this M.O. because it's similar as what NASA and the Pentagon does in real life: a call for applications, then they take every applicant and test themselves. It's how we, as "designers", see how the thing will be really used, and then have to adapt. It's an additional challenge: it's not enough to do the "best" craft, I need to do a craft than the client (you) can use himself to reach their goal.

There's a fabulous history about how the X-15 won the proposal, besides the Douglas D684 being a "better" applicant!

Spoiler

 

 

[Triop]

21 minutes ago, Lisias said:

Just some disagreements on how to interpret things.

That's easy for you to say, you are not the one who had to decide the fate of @qzgy, it's not fun being a judge.

21 minutes ago, Lisias said:

It's healthy, it's what drive us ahead and make us do better things in the future.

It sure is, that's why people hold competitions.

21 minutes ago, Lisias said:

I like this M.O. because it's similar as what NASA and the Pentagon does in real life

Indeed, see the YF-22 vs YF-23 contract (bye bye boeing ) edit: I voted for the YF-23

21 minutes ago, Lisias said:

it's not enough to do the "best" craft, I need to do a craft than the client can use himself to reach their goal.

Good point.

Thanks for your input Lis, you are 100% right.

Edited March 31, 2019 by Triop

[swjr-swis]

3 hours ago, Triop said:

I suggest download the mod, do the run and send in the results.

 

Fine... one mod, this one time.

Spoiler

1.94 seconds on Triop's 1km drag race track.

It runs out of fuel a good bit before reaching the 1km checkpoint. I tried a few runs adding another tick of fuel, but then it apparently goes too fast for the mod to register passing the second checkpoint (886 m/s at flame out), and it never gives me a finished race. I guess 1.94s is the best result the mod will let me record.

[Triop]

35 minutes ago, swjr-swis said:

1.94 seconds on Triop's 1km drag race track.

Wow, That's fast.

Looks legit, where were you the last few weeks ? 

You're on the score board.

Scoreboard:

1: swjr-swis - 01:94

2: HB Stratos - 02.84

3: Lisias - 03.38

4: sturmhauke - 03.44

5: NBDesign - 03.48

6: Ultimate Steve - 03:58

7: Jacke - 03.70

8: Gapone - 05.44

9: qzgy - fastest time, but not official, hope to see you back Q

 

37 minutes ago, swjr-swis said:

I guess 1.94s is the best result the mod will let me record.

I guess we can solve that by making the track longer, like 1500 meters or 2000 meters.

Pretty cool you outrun the mod though.

Edited March 31, 2019 by Triop

[Lisias]

7 hours ago, swjr-swis said:

I tried a few runs adding another tick of fuel, but then it apparently goes too fast for the mod to register passing the second checkpoint (886 m/s at flame out), and it never gives me a finished race. I guess 1.94s is the best result the mod will let me record.

Nops. It's a glitch on RACE!. Sometimes, the Physics Delta-Time makes it miss the line crossing. Just  a bit faster, or just a bit slower, ande then the line crossing happens inside the detection window.

You can try to mangle with the "Max Physics Delta Time" option on the Main Menu/Settings to see what you get.

 

— — — POST EDIT — — — 

In time…. MOAR BOOSTERS Edition : 2.86s !! :-)

http://kerbalx.com/Lisias/Triops-Dragster-Challenge-Mark-1

 

Boy, the worst part was to trim the escape system to land exactly on the end of the runway.  

Edited March 31, 2019 by Lisias
MOAR BOOSTERS! :)

[Triop]

2 hours ago, Lisias said:

In time…. MOAR BOOSTERS Edition : 2.86s !! :-)

Nice, I've updated the scoreboard. Cool to see you defend your 3th 2nd place.

2: Lisias - 03.38 - 02.86

Edited March 31, 2019 by Triop

[swjr-swis]

8 hours ago, Triop said:

where were you the last few weeks ? 

Lots of things going on that are messing with my gaming time, unfortunately. I've been testing and tweaking intermittently with a few experimental drag racers since you started this thread. But since I can't tell from one day to the next when I'll have time to finish any KSP project, I didn't speak up to get added to the racing schedule. I figured if I ever managed to get a semi-worthy run I'd just post it and get an honorary mention or something.

 

8 hours ago, Triop said:

You're on the score board.

Triop, do notice that I don't have any wheels on my 'car' - I fully accept I am bending the definition, as evidenced by using the word between quotes even on the craft page. I'm fine with being barred from the actual scoreboard, which is what I expected. Besides, it was more of an encouragement to @qzgy to make his design comply with safety regulations and take that first spot.

 

For the record: I have a version of the Egg with wheels that I still need to tweak to deal with the murderously wonky wheel physics, but no successful run recorded yet. So if that ever runs without scratching the runway, I may enter an actual car.

[Triop]

19 minutes ago, swjr-swis said:

Triop, do notice that I don't have any wheels on my 'car'

Wut ?

19 minutes ago, swjr-swis said:

I'm fine with being barred from the actual scoreboard, which is what I expected.

I have to...

19 minutes ago, swjr-swis said:

For the record: I have a version of the Egg with wheels that I still need to tweak to deal with the murderously wonky wheel physics, but no successful run recorded yet. So if that ever runs without scratching the runway, I may enter an actual car.

Goodluck.

Scoreboard:

1: HB Stratos - 02.84

2: Lisias - 03.38 - 02.86

3: sturmhauke - 03.44

4: NBDesign - 03.48

5: Ultimate Steve - 03:58

6: Jacke - 03.70

7: Gapone - 05.44

8: qzgy - fastest time, but not official, hope to see you back Q

Edited March 31, 2019 by Triop