The Great Kerbal Race

[Guest]

COMPETITION CLOSED

Welcome to the official 2017 G.K.R!

In this challenge, you have one goal: to drive a rover to the exact north pole and return back to the KSC as quickly as possible.

 

Rules:

There can be one kerbal on board.

The only non-stock parts that may be used are FAR, mechjeb, or KIS(or any other autopilot systems)

The only propulsion systems that may be used are rover wheels, jets, and mono prop engines.

It must not (intentionally) leave ground level.

You must post pictures showing MET at start and finish.

It ends on 3/25/17

Have fun!

Edited March 25, 2017 by Guest
Added Mod

[Triop]

I like the idea, but some pointers:

- There can be one kerbal on board.  Can or has to ?

- The only propulsion systems that may be used are rover wheels. That is gonna take 4ever.

...............................and return back to the KSC as quickly as possible.     nope nope nope. . .

Have you done it ? Don't believe it can be done...

Driving to the pole and planting a flag there is a great idea. make this work.

The last polar part would be long boring white flatlines going 50 m/s with only rover wheels.

 

We test dragsters there !    give us rocket power. 

Edited January 25, 2017 by Triop

[Guest]

On January 24, 2017 at 5:55 PM, Triop said:

I like the idea, but some pointers:

- There can be one kerbal on board.  Can or has to ?

- The only propulsion systems that may be used are rover wheels. That is gonna take 4ever.

...............................and return back to the KSC as quickly as possible.     nope nope nope. . .

Have you done it ? Don't believe it can be done...

Driving to the pole and planting a flag there is a great idea. make this work.

The last polar part would be long boring white flatlines going 50 m/s with only rover wheels.

 

We test dragsters there !    give us rocket power. 

It can be unmanned(although I wouldn't do it, due to breaking wheels)

and, I am allowing jets and mono prop.

[Cunjo Carl]

I'm on my way

Go, Scuttlebutt, go!

edit: Awh... KSP crashes before I did... . I found 80-100m/s was a pretty safe speed given the bumps despite the occasional mishap. This is my first real terrestrial rover so I don't have a lot of context. What's a typical speed for cruising on the turf?

Edited January 28, 2017 by Cunjo Carl

[Linventor]

On 1/28/2017 at 1:45 AM, Cunjo Carl said:

What's a typical speed for cruising on the turf?

When you're Jeb? Mach . Duh.

Edited January 28, 2017 by Linventor

[Cunjo Carl]

4 minutes ago, Linventor said:

When you're Jeb? Mach 8. Duh.

What? For Reals?? That's awesome! How do you contact the ground given the lumps and bumps?

[Linventor]

On 1/28/2017 at 11:38 AM, Cunjo Carl said:

What? For Reals?? That's awesome! How do you contact the ground given the lumps and bumps?

...

That was a joke... Mach is over orbital velocity for Kerbin.

[Cunjo Carl]

 

7 minutes ago, Linventor said:

That was a joke... Mach is over orbital velocity for Kerbin.

It's possible to keep low with negative lift from wings. People do some crazy things in this game

Escape Velocity: The Hypersonic Race

[Linventor]

On 1/28/2017 at 11:49 AM, Cunjo Carl said:

 

It's possible to keep low with negative lift from wings. People do some crazy things in this game

Escape Velocity: The Hypersonic Race

I've noticed. Also, you made me miss my maneuver node by a minute! Good thing it was around 25 m/s...

 

Another thing: ya like that font I've got for the ?

Edited January 28, 2017 by Linventor

[Cunjo Carl]

44 minutes ago, Linventor said:

Another thing: ya like that font I've got for the ?

It's quite burny!

 

The march of progress continues. I'm now stable at 160m/s cruising speeds for long distances thanks to an eliptical wheel base and more aero control surfaces for stabilization. The speed limiter really has been the little bumps!

Here's hoping I have an excuse to use the "VTOL" Junos at some point. I know flying is against the rules, but it's not really flying with those... It's falling with style.

[Linventor]

21 minutes ago, Cunjo Carl said:

It's quite burny!

 

The march of progress continues. I'm now stable at 160m/s cruising speeds for long distances thanks to an eliptical wheel base and more aero control surfaces for stabilization. The speed limiter really has been the little bumps!

Here's hoping I have an excuse to use the "VTOL" Junos at some point. I know flying is against the rules, but it's not really flying with those... It's falling with style.

I can't see the image. Also, when I try to look at it by right-clicking it and clicking "view image", it says there isn't a secure connection.

EDIT: For some reason, in my email inbox, I can view the image, even though I can't here.

EDIT 2: For some reason, 13 minutes after my first edit, the pics work again, for some reason. Also, I gtg eat lunch.

Edited January 28, 2017 by Linventor

[Guest]

48 minutes ago, Cunjo Carl said:

It's quite burny!

 

The march of progress continues. I'm now stable at 160m/s cruising speeds for long distances thanks to an eliptical wheel base and more aero control surfaces for stabilization. The speed limiter really has been the little bumps!

Here's hoping I have an excuse to use the "VTOL" Junos at some point. I know flying is against the rules, but it's not really flying with those... It's falling with style.

Please don't use engines if above ground.

[Guest]

11 hours ago, Cunjo Carl said:

-snip-

edit: Awh... KSP crashes before I did... . I found 80-100m/s was a pretty safe speed given the bumps despite the occasional mishap. This is my first real terrestrial rover so I don't have a lot of context. What's a typical speed for cruising on the turf?

You're using 1.1.x,(like me) right?

[Linventor]

I'm back from lunch

 

[OrbitalBuzzsaw]

Did you get the idea from my challenge? If so, thank you.

[Cunjo Carl]

I'm happy to get rid of them if you'd like, but you might be ok with them if you know their purpose. They're actually the 'stop flying' jets. When you hit a bump going downhill, it can bounce the front end of the car up. That causes a bunch of body lift (even with mk1), and if it overcomes the rear spoilers can cause flight. If you try to pitch down to stop flying you land way too hard and explode, so I installed a way to stop flying gracefully. By hitting an action command, the craft activates the airbrakes and turns on the vertical fans. This gives you just enough float to let you pitch down to match the ground and land. It necessarily cuts your speed a lot so I avoid it as much as possible, but on our 2,500km journey the ability to stop accidentally flying should be very handy.

Still totally cool if you'd like me to nix it. I'm sure I'll find a way, or just toodle on the downhills!

I don't normally update so much, but as long as I'm here
 

Spoiler

Made it a little further, but lost it while checking my map in the foothills.

 

Edited January 28, 2017 by Cunjo Carl
airbrakes are nice

[Guest]

4 hours ago, Cunjo Carl said:

I'm happy to get rid of them if you'd like, but you might be ok with them if you know their purpose. They're actually the 'stop flying' jets. When you hit a bump going downhill, it can bounce the front end of the car up. That causes a bunch of body lift (even with mk1), and if it overcomes the rear spoilers can cause flight. If you try to pitch down to stop flying you land way too hard and explode, so I installed a way to stop flying gracefully. By hitting an action command, the craft activates the airbrakes and turns on the vertical fans. This gives you just enough float to let you pitch down to match the ground and land. It necessarily cuts your speed a lot so I avoid it as much as possible, but on our 2,500km journey the ability to stop accidentally flying should be very handy.

Still totally cool if you'd like me to nix it. I'm sure I'll find a way, or just toodle on the downhills!

I don't normally update so much, but as long as I'm here
 

  Hide contents

Made it a little further, but lost it while checking my map in the foothills.

 

You can keep it.

5 hours ago, OrbitalBuzzsaw said:

Did you get the idea from my challenge? If so, thank you.

Actually, it wasn't. I thought of it after remembering the 2009(or 2007) DARPA Grand Challenge.

[OrbitalBuzzsaw]

9 hours ago, dundun92 said:

You can keep it.

Actually, it wasn't. I thought of it after remembering the 2009(or 2007) DARPA Grand Challenge.

hmm.

[DoctorDavinci]

20 hours ago, OrbitalBuzzsaw said:

Did you get the idea from my challenge? If so, thank you.

TBH I think you got your idea from all the discussions that started after the Kerbin Dakar Idea thread was posted back in December 

Why you gotta hate? ... It is obviously getting on the bandwagon with everyone else who has either tried hijacking or copying the original idea

If anyone should be 'complaining' that their idea was 'stolen' it should be @Triop ... however, do you see him complaining about someone else making a clone of his challenge?

It's a game ... remember that

Edited January 29, 2017 by DoctorDavinci

[OrbitalBuzzsaw]

1 hour ago, DoctorDavinci said:

TBH I think you got your idea from all the discussions that started after the Kerbin Dakar Idea thread was posted back in December 

Why you gotta hate? ... It is obviously getting on the bandwagon with everyone else who has either tried hijacking or copying the original idea

If anyone should be 'complaining' that their idea was 'stolen' it should be @Triop ... however, do you see him complaining about someone else making a clone of his challenge?

It's a game ... remember that

Not hating, just curious as to how much people are paying attention to my challenge because there's not seeming to be much interest.

[DoctorDavinci]

1 minute ago, OrbitalBuzzsaw said:

Not hating, just curious as to how much people are paying attention to my challenge because there's not seeming to be much interest.

Perhaps there isn't much interest due to the amount of clones of the original Dakar challenge that have popped up since the idea was first posted to the forum

Think about it, there was even a challenge posted that was almost a direct copy of the original within one day of it being posted with the additional faux-pas of the clone challenge creators trying to hijack the original thread to promote their own copy of the idea ... On top of that there must be 3 or 4 other rally racing challenges that have appeared in the past month of which only one was an original take on the idea (Munar Dakar)

[Guest]

How do you stop it from steering wildly at 100+ m/s?

[Cunjo Carl]

4 hours ago, dundun92 said:

How do you stop it from steering wildly at 100+ m/s?

There's a few tricks to it. I've finally got my craft stabilized well at 150-225m/s on anything but the mountains, though the occasional pothole still wrecks my day. Certainly, not all of these are necessary but I hope some of them help.

0. I'm assuming you're using the little wheels? They work nice.

00. If any of the wheels are facing backwards, you may need to set them on inverted steering.... maybe? I can't remember. Make sure to give it a check!

1. Use friction control (a button toggleable option when right-clicking the wheel) to make the front wheels slippy and the back wheels grippy. This is very similar to making a plane, where you want the "grippy" tail fin to be in the back. With the car, grippy wheels get pulled backwards, so you want the back of your car to be the grippiest. In practice, I find a friction of 0.5 for the front wheels and 2.5 for the rear wheels work nicely. Using jet engines (like wheesly) we'll have plenty of thrust to spare. Alternatively, you could put more wheels in the back, but for reason 3.5, that's not the best solution.

2. Put a tailfin on your car. It doesn't need to be big (even elevon 4s should do), but I found three AV-R8s in the standard left/right/up configuration worked very well. This is for exactly the same reasons as above. What's more, If your tailfin has active control surfaces like the AV-R8 or elevons, they can really help to dampen oscilations from bouncing, and can help you line up your car with the ground when landing a jump. Regardless of your intentions, at 200m/s you definitely jump.

3. Make the very front wheels springy and "soft" and the central/back wheels increasingly stiffer to help reduce bucking at high speeds (where the front jumps up and down like a trampoline). Those very front wheels often take the brunt of any misalignments you have with the ground when landing a jump, and making then soft will allow your car to spread out the force more evenly and thus rebound less erratically. Similarly, any wheels on the left/right centerline of your car can be made stiffer (and the left/right-most ones softer) to help with side to side bucking.

3.5. Have lots of those little wheels! I think my 7ton car has 25 of them. Having more helps to spread out the weight, especially when taking advantage of the softer front wheels. It also provides redundancy. Probably goes without saying, but all the wheels should be at the same height.

4. With so many wheels, an elliptical wheel base about 2-3x longer than wide helps a ton with stability issues from landing one corner first. Just the same as above, the elliptical shape allows the stress to spread out more evenly. I'd recommend 'filling in' the middle of the ellipse as well.

5. Use spoilers on the back. I chose to use a pair of basic fins on each side, tilted down 10 degrees from flat. These help tremendously to hold you to the ground, which will keep your traction much better and prevent explosions from jumping too high. My car stays on the ground 98% of the time, and that 2% in the air is always the scary part. Going with a shallower angle (optimal ~3 deg) provides less drag for a given downwards push but you'd need an increasingly large spoiler. That's not really a downside, I just didn't like the look. Anyway, choosing the right amount of spoiler is a very careful balance, and I'll feign no good heuristic for success. Go Kerbal. Try try again!

6. A couple reaction wheels somewhere in the mix helps a lot with damping little oscilations, I'd recommend them. Where you put them doesn't matter much on a small car.

7. Completely unrelated to stability: find some way to land unfortunate jumps! I'm using little jump jets (they're just barely effective enough), but my brief trial with airbrakes tilted to provide a jolt of body lift looked promising. At 200m/s you'll find yourself all too often going over a hill and suddenly 10m in the air without your consent. Given the spoilers pushing down so hard, you need something to give you a little shot of up before landing. All of my successful techniques have also involved radically slowing down, though I'm not sure if it's necessary.

I hope that wasn't too much text... Well good luck with your crazy car! I'm looking forward to seeing it if/when it takes shape.

[Guest]

15 minutes ago, Cunjo Carl said:

There's a few tricks to it. I've finally got my craft stabilized well at 150-225m/s on anything but the mountains, though the occasional pothole still wrecks my day. Certainly, not all of these are necessary but I hope some of them help.

0. I'm assuming you're using the little wheels? They work nice.

00. If any of the wheels are facing backwards, you may need to set them on inverted steering.... maybe? I can't remember. Make sure to give it a check!

1. Use friction control (a button toggleable option when right-clicking the wheel) to make the front wheels slippy and the back wheels grippy. This is very similar to making a plane, where you want the "grippy" tail fin to be in the back. With the car, grippy wheels get pulled backwards, so you want the back of your car to be the grippiest. In practice, I find a friction of 0.5 for the front wheels and 2.5 for the rear wheels work nicely. Using jet engines (like wheesly) we'll have plenty of thrust to spare. Alternatively, you could put more wheels in the back, but for reason 3.5, that's not the best solution.

2. Put a tailfin on your car. It doesn't need to be big (even elevon 4s should do), but I found three AV-R8s in the standard left/right/up configuration worked very well. This is for exactly the same reasons as above. What's more, If your tailfin has active control surfaces like the AV-R8 or elevons, they can really help to dampen oscilations from bouncing, and can help you line up your car with the ground when landing a jump. Regardless of your intentions, at 200m/s you definitely jump.

3. Make the very front wheels springy and "soft" and the central/back wheels increasingly stiffer to help reduce bucking at high speeds (where the front jumps up and down like a trampoline). Those very front wheels often take the brunt of any misalignments you have with the ground when landing a jump, and making then soft will allow your car to spread out the force more evenly and thus rebound less erratically. Similarly, any wheels on the left/right centerline of your car can be made stiffer (and the left/right-most ones softer) to help with side to side bucking.

3.5. Have lots of those little wheels! I think my 7ton car has 25 of them. Having more helps to spread out the weight, especially when taking advantage of the softer front wheels. It also provides redundancy. Probably goes without saying, but all the wheels should be at the same height.

4. With so many wheels, an elliptical wheel base about 2-3x longer than wide helps a ton with stability issues from landing one corner first. Just the same as above, the elliptical shape allows the stress to spread out more evenly. I'd recommend 'filling in' the middle of the ellipse as well.

5. Use spoilers on the back. I chose to use a pair of basic fins on each side, tilted down 10 degrees from flat. These help tremendously to hold you to the ground, which will keep your traction much better and prevent explosions from jumping too high. My car stays on the ground 98% of the time, and that 2% in the air is always the scary part. Going with a shallower angle (optimal ~3 deg) provides less drag for a given downwards push but you'd need an increasingly large spoiler. That's not really a downside, I just didn't like the look. Anyway, choosing the right amount of spoiler is a very careful balance, and I'll feign no good heuristic for success. Go Kerbal. Try try again!

6. A couple reaction wheels somewhere in the mix helps a lot with damping little oscilations, I'd recommend them. Where you put them doesn't matter much on a small car.

7. Completely unrelated to stability: find some way to land unfortunate jumps! I'm using little jump jets (they're just barely effective enough), but my brief trial with airbrakes tilted to provide a jolt of body lift looked promising. At 200m/s you'll find yourself all too often going over a hill and suddenly 10m in the air without your consent. Given the spoilers pushing down so hard, you need something to give you a little shot of up before landing. All of my successful techniques have also involved radically slowing down, though I'm not sure if it's necessary.

I hope that wasn't too much text... Well good luck with your crazy car! I'm looking forward to seeing it if/when it takes shape.

I tried two designs... None sucedded. Thanks for the tips!

[Guest]

Here are my failed cars: