KSP Challenge: "Target Practice"

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On 12.01.2018 at 3:40 AM, AngrybobH said:

I made about 50 attempts with a 5400 dV single stage missile without the assistance of any mods. It seems the precision required for a bullseye shot from the launch pad is not possible with the stock controls except for dumb luck. Well, I know it is technically possible especially considering exactly where the target is but, I cannot do it. I may use mechjeb and try again or I may just bow out of this one.

Here's my estimate. Hitting a 5m target from the distance of 12 Mm (radius of Mun orbit) requires angular precision 5m / (12×106m) = 4.17×10-7 rad = 2.4×10-5°. The slowest angular motion you have is the daily rotation of Kerbin which has the angular speed of 360°/6hrs = 0.0167°/s. So, the desired angular precision requires timing accuracy of 2.4×10-5° / (0.0167°/s) = 0.0014s or better. In-game physics tick is 0.02s, an order of magnitude larger. So, unless you're very lucky or know secret throttling techniques to make time of travel an exact multiple of physics tick duration, it's impossible to hit target precisely.

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What is the deadline for this challenge?

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It was my new year's resolution to at least attempt the KSP challenges this year! During my best attempt I forgot to hit record... This was my second best. I have Kerbal Engineer Installed, but it was not used in any meaningful way for this challenge.

100 - 4 + 2 = 96 total

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On 1/12/2018 at 11:42 AM, Adelaar said:

Nice challenge this. I've done this the old school way, without mods (so all manual flying and no usage of mods to intercept the target).

On 1/16/2018 at 7:47 PM, Jeb, The Lonely Kerbonaut said:

What is the deadline for this challenge?

Jan 23 is the last day

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On 1/10/2018 at 11:37 AM, linuxgurugamer said:

• @Red Shirt hit the planet, but didn't show the distance, also no craft file.  Score: 12

Broad side of the barn - Woo Hoo! I'll take it. Did no better on later attempts.

Mods: Squad/Porkjet stock parts, Mechjeb to establish 75k Ap. Transfer by free hand burn without circularizing

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1 hour ago, Red Shirt said:

Broad side of the barn - Woo Hoo! I'll take it. Did no better on later attempts.

Mods: Squad/Porkjet stock parts, Mechjeb to establish 75k Ap. Transfer by free hand burn without circularizing

I didn't see the impact image in your imgur album, were you more than 100km from the cabin?

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1 hour ago, linuxgurugamer said:

I didn't see the impact image in your imgur album, were you more than 100km from the cabin?

It was 55km but no proof shot. Thought I was doing it wrong at the time,

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13 minutes ago, Red Shirt said:

It was 55km but no proof shot. Thought I was doing it wrong at the time,

Ok, I'll accept that

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Used the Trajectories mod, was just 290m short of the Minmus shack. Used rcs to fine tune after the main burn.

Save file with the impactor on its final jorney: https://www.dropbox.com/s/g2n1nywuk36o5h3/quicksave.sfs?dl=0

It is possible to hit the shack directly with a small RCS correction in Minmus' SOI using the readings from KER.

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2 hours ago, Enceos said:

Used the Trajectories mod, was just 290m short of the Minmus shack. Used rcs to fine tune after the main burn.

At what point did you use the RCS?  immediatly after the main burn?  or some time after?

Was this a single burn to the injection or was there two burns plus the rcs?

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7 hours ago, linuxgurugamer said:

At what point did you use the RCS?  immediatly after the main burn?  or some time after?

Was this a single burn to the injection or was there two burns plus the rcs?

One burn plus RCS immediately after that. Forgot to save at that time, so my craft is a little past the munar orbit in the save file.

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4 hours ago, Enceos said:

One burn plus RCS immediately after that. Forgot to save at that time, so my craft is a little past the munar orbit in the save file.

Ok, since the RCS was immediate, I'll consider it to be part of the second burn.

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So, this time I left the "Targeting Computer" on  and used RCS  to fine-tune my course immediately after finishing the burn, using the same maneuver node that I set up in my last attempt. Then I decoupled, which threw the course off that tiny bit, so I again put it back on course with RCS, so the Trajectories window showed 0.0m. As far as I'm concerned, using Trajectories this way is against the spirit of the challenge if not the actual rules (especially at Munar range), so I don't expect this to count. Even so, I missed the cabin by a mere 28.5m. I had to turn the cabin light on (more lights would have been nice) to even see it, as well as slow the video right down.

I might take a crack at hitting the Minmus Cabin later, but I want to work on my career save too. Decisions, decisions, priorities (of which my wife would say KSP is not a priority, but what does she know...)

Edited by StrandedonEarth
Maybe I should proofread before posting
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On 1/10/2018 at 5:13 PM, FuzzyHead said:

Alrigh, I did it

Still haven't figured out how to properly link imgur now. It used to be possible to see the pics right here in the post. Cant do that anymore...

Was a little easier than I expected.

Album https://imgur.com/a/Oosxp will appear when post is submitted

click the square with the i on it and enter the album code.

alternatively, if you are mot using imgur,drag the image into the post you are writing.

On 1/10/2018 at 5:13 PM, FuzzyHead said:

Alrigh, I did it

Still haven't figured out how to properly link imgur now. It used to be possible to see the pics right here in the post. Cant do that anymore...

Was a little easier than I expected.

Album https://imgur.com/a/Oosxp will appear when post is submitted

click the square with the i on it and enter the album code.

alternatively, if you are mot using imgur,drag the image into the post you are writing.

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Challenge is over, badges have been distributed.

Thanks to all who submitted entries

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My gosh, too late... (and too far)
It was a very interesting challenge and I hope that "Target Practice 2" will be held.

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A for effort