tips for fast rovers?

[jaunco325]

Can anyone tell me how I could make a rover that is controllable at high speeds?

[bewing]

At what level of gravity, and atmosphere or no atmosphere? Those are the two biggest design issues.

[GDJ]

14 minutes ago, jaunco325 said:

Can anyone tell me how I could make a rover that is controllable at high speeds?

There are a lot of factors that are involved with high speed rovers, just like cars in real life. What issues are you having?

[Cavscout74]

It helps to have more info as atmosphere & gravity make a big difference, but as a general rule having the center of mass as low as possible will help keep them from flipping. Also, wider rovers are better at not flipping.

[jaunco325]

Now I am having problems in mun and minmus. I already tried to make it flat and wide, but it is not enough. I tried to put RCS thrusters at the ends but it only worked with small, small-wheel rovers.

Edited March 9, 2020 by jaunco325

[GDJ]

1 hour ago, jaunco325 said:

Now I am having problems in mun and minmus. I already tried to make it flat and wide, but it is not enough. I tried to put RCS thrusters at the ends but it only worked with small, small-wheel rovers.

You're dealing with almost nil for gravity. That's the problem. You just can't go that fast on the Mun, and Minmus you're doing good if you get 15 m/s without bouncing around like a beachball.

Try softer spring, dampener, and adjust friction settings on the wheels. You may have to open up the Advanced Tweakables for this.

Edited March 10, 2020 by GDJ

[jaunco325]

The problem is not the rebounds, they are the spins. if it bounces and rises in the air I don't care because it will land with the same ease with which it rises. The problem is that the creators never drove a car, and they don't understand that the wheels need a different angle of rotation according to the speed of the vehicle.
Friction, maybe it's useful, thanks.

[GDJ]

1 hour ago, jaunco325 said:

Can anyone tell me how I could make a rover that is controllable at high speeds?

 

1 hour ago, jaunco325 said:

Now I am having problems in mun and minmus. I already tried to make it flat and wide, but it is not enough. I tried to put RCS thrusters at the ends but it only worked with small, small-wheel rovers.

 

2 minutes ago, jaunco325 said:

The problem is not the rebounds, they are the spins. if it bounces and rises in the air I don't care because it will land with the same ease with which it rises. The problem is that the creators never drove a car, and they don't understand that the wheels need a different angle of rotation according to the speed of the vehicle.
Friction, maybe it's useful, thanks.

Look, I want to help you here, but you got to throw us a few more bones than what you're doing.

So the rovers are spinning out. What else?

[Agustin]

install kspWheel

Also kerbal Foundries; 
And download the stock wheels patches from the girhub web of kerbal foundries:

https://github.com/shadowmage45/KerbalFoundries2/tree/master/KerbalFoundries-Patches

Edited March 10, 2020 by Agustin

[jaunco325]

1 hour ago, GDJ said:

 

 

Mira, quiero ayudarte aquí, pero tienes que arrojarnos unos cuantos huesos más de lo que estás haciendo.

Entonces los rovers están girando. ¿Qué más?

Sorry, maybe I expressed myself wrong. My main problem is that when you turn the vehicle at high speeds, it flies out. and as I always deviate from the direction in which I drive, I have to be correcting it all the time, which is very dangerous. and I also don't want to have to brake the entire vehicle to rearrange it every 15 seconds.

1 hour ago, Agustin said:

instalar kspWheel

También fundiciones kerbal; 
Y descargue los parches de ruedas de stock de la web girhub de fundiciones de kerbal:

https://github.com/shadowmage45/KerbalFoundries2/tree/master/KerbalFoundries-Patches

interesting, I'll try it, thanks

[Kerbart]

6 minutes ago, jaunco325 said:

Sorry, maybe I expressed myself wrong. My main problem is that when you turn the vehicle at high speeds, it flies out. and as I always deviate from the direction in which I drive, I have to be correcting it all the time, which is very dangerous. and I also don't want to have to brake the entire vehicle to rearrange it every 15 seconds.

You're up against physics. Those are fights one usually doesn't win (read: Tin-tin and the Rocket Equation)

To make a turn with radius r at velocity v you will need a force of F = mv²/r  (1)
Now, the force your tires can deliver is dependent on a friction coefficient times the normal force, which under normal circumstances is in equilibrium with gravity; so that F = µF_g = µmg (2)
Combining (1) and (2) we get mv²/r = µmg which can be simplified to v² = µgr

Note that this means you cannot increase down force by increasing your mass (weight) - the two cancel each other out. If you want to turn at higher velocity, you simply have to increase your turn radius. Notice that small g factors really impact your ability to make small radius turns. Guess what the g-force on Minmus is?

 

On Earth there are a couple of tricks you can apply but I doubt those work on Minmus:

• You can use really soft, sticky rubber to increase your µ friction factor. Of course they wear out really fast, but you can mitigate that by reducing the load on the tire per square centimeter (or inch if you're into freedom units). That's why race cars have wide tires. Note that it's not the wide tires that give you the grip, so simply adding more wheels won't help; it's the extra soft rubber that you'd use that wide tires allow. You can't really change the rubber compound in KSP though; so that is not an option.
• You can use aerodynamics to create extra downforce, thus increasing the total amount of friction tires can produce. Sadly Minmus  has no atmosphere. But you can create extra downforce by having some downward pointing engines mounted that you fire up whenever making a turn...

 

 

[OHara]

I use both hands. 

In 'Settings' you can add I J K L keys as secondary controls for driving (on PC, on extra inputs if you have them on a console) then you control wheels with the right hand IJLK,  and rotation of the craft with the left hand WASD.

Usually, you can let SAS  control reaction wheels and/or RCS to hold prograde as you bounce over the bumps.  SAS does not try to steer the wheels.

For me, this changes the experience of driving a rover on the Mun from a frustrating challenge to a fun challenge.

[jaunco325]

1 hour ago, Kerbart said:

you simply have to increase your turn radius

It's what I would like to do, but the game doesn't let me. I can't limit the angle of rotation of the wheels.

1 hour ago, Kerbart said:

• You can use aerodynamics to create extra downforce, thus increasing the total amount of friction tires can produce. Sadly Minmus  has no atmosphere. But you can create extra downforce by having some downward pointing engines mounted that you fire up whenever making a turn...

I already tried to put RCS thrusters that pointed downwards, so that when the turns were turned on, the thrusters on the inner side of the turn were turned on, but this only worked on small rovers. What I do not try is that the propellers ignite all at the same time hitting the whole ship to the ground regardless of the direction of the turn, but I do not know if this would be could cancel itself.

43 minutes ago, OHara said:

I use both hands. 

In 'Settings' you can add I J K L keys as secondary controls for driving (on PC, on extra inputs if you have them on a console) then you control wheels with the right hand IJLK,  and rotation of the craft with the left hand WASD.

Usually, you can let SAS  control reaction wheels and/or RCS to hold prograde as you bounce over the bumps.  SAS does not try to steer the wheels.

For me, this changes the experience of driving a rover on the Mun from a frustrating challenge to a fun challenge.

very interesting solution, thanks

[OHara]

53 minutes ago, jaunco325 said:

I can't limit the angle of rotation of the wheels.

True.  The best we can do is use the fine-control mode ('caps lock' or 'bloq mayús' on PC) so that the keys turn the steering more slowly. 
Then we can tap the L key (or D in the default setup) to turn weakly to the right.

[TheFlyingKerman]

Here my solution differs from the others. I just accept the rover crashing, and design a small rover that survives the crash and then rights itself using reactions wheels (the low gravity and overpowered electric parts helps).

l routinely drive 50m/s + on the Mun and Minmus for hundreds of km. I would zoom out and look ahead for a straight and relatively flat path, reducing speed when I need to turn. I also use IJKL to drive and WSAD to control my position mid flight.

[Superfluous J]

Mine differs as well. If a world is too low gravity to support a rover (ie, not Eve, Tylo, or Kerbin. And maybe Duna) I instead use a hopper. The hopper may have wheels for the last few meters but any real distance is covered via rocket.

[George411]

9 hours ago, Agustin said:

install kspWheel

Also kerbal Foundries; 
And download the stock wheels patches from the girhub web of kerbal foundries:

https://github.com/shadowmage45/KerbalFoundries2/tree/master/KerbalFoundries-Patches

Is this toolkit available from Google Playstore?

[Guest]

2 hours ago, 5thHorseman said:

Mine differs as well. If a world is too low gravity to support a rover (ie, not Eve, Tylo, or Kerbin. And maybe Duna) I instead use a hopper. The hopper may have wheels for the last few meters but any real distance is covered via rocket.

Same, except that on Kerbin, Eve, and often Duna I use propeller-driven or rotorcraft instead. Tylo is made for rovers. I also use them on roughly Mun-sized bodies. 

I can make a rover that's reasonably safe to drive at up to 25 m/s or so on the lighter-gravity bodies, 35 m/s or so on Tylo. But Minmus-scale bodies are strictly hoppers only. 

[Hotel26]

11 hours ago, jaunco325 said:

The problem is not the rebounds, they are the spins

I use reaction wheel stability under the control of SAS.  40 m/s but a high duty cycle in 'space', low over the surface.  The trick is landing.  I generally use both a horizontal (prograde) reference and a vertical (Radial Out) for landing the jumps.

In detail, Prograde into the jump and then SAS Hold to lock the attitude when flat (or in the attitude I estimate will match the landing) and then Vert ref and Radial Out to nail a rough landing or to straighten out a botched launch.

You go high speed to get somewhere in a straight line, not make turns.  So, like a boat, if you want to turn (to navigate around an obstacle) you have to be prepared to slow down, sometimes almost to a stop, to make the turn and then accelerate onward.  Trains are the same.

Some patience is involved.

Edited March 10, 2020 by Hotel26

[mystifeid]

36 minutes ago, Brikoleur said:

Tylo is made for rovers

This. Also Val. On both, long-ish downhill slopes make it easy to keep purely wheel driven rovers at over 100m/s for nail biting lengths of time although risk increases exponentially at anything over 80-90m/s. With a little rocket assist the large craters on Moho and of course the polar icecaps on Kerbin are also excellent. But Tylo - the equator is like one big long race track with the odd minefield thrown in for good measure.

[Kerbart]

11 hours ago, jaunco325 said:

It's what I would like to do, but the game doesn't let me. I can't limit the angle of rotation of the wheels.

Shile risking pointing out things you probably already implemented:

• longer wheel base
• only front wheels steer

It’s more mitigation than anything else though...

[jaunco325]

11 hours ago, OHara said:

True.  The best we can do is use the fine-control mode ('caps lock' or 'bloq mayús' on PC) so that the keys turn the steering more slowly. 
Then we can tap the L key (or D in the default setup) to turn weakly to the right.

Could you give me more details of where that option is?

4 hours ago, Hotel26 said:

You go high speed to get somewhere in a straight line, not make turns.

It is impossible to keep the line straight, the smallest variation of the terrain will divert the direction of the rover.

1 hour ago, Kerbart said:

Shile risking pointing out things you probably already implemented:

• longer wheel base
• only front wheels steer

It’s more mitigation than anything else though...

I didn't think about the wheelbase, thanks

[Agustin]

8 hours ago, George411 said:

Is this toolkit available from Google Playstore?

what for? and I don´t think so, no.

[OHara]

2 hours ago, jaunco325 said:

Could you give me more details of where that option is?

When you are controlling the rover, the CapsLock key (on PC) turns the pitch/yaw/roll indicators blue.  When the indicators are blue, pressing W A S D (and I J K L if enabled) briefly moves the pitch/yaw/roll indicators from the center relatively slowly while the keys are pressed.  By tapping the keys, you can make small inputs.

Some things about 'precision mode' can be confusing.  The animations of some parts move just as fast whether precision-control mode is active, but the effect of W A S D is slowed.  It works when I J K L control wheels, even though the pitch/yaw/roll indicators do not move.  It does not work for some of the landing gear.

18 hours ago, jaunco325 said:

The problem is that the creators [ ...] don't understand that the wheels need a different angle of rotation according to the speed of the vehicle.

It looks like that was understood, and part of the plan, because KSP wheels have configuration settings for how much to reduce the steering angle as a function of speed, but this feature was dropped (the relevant bug report).  You probably have noticed that KSP shows signs of being started by people with some very good ideas, but not enough technical capacity to make all those ideas work in the complex and imperfect world of coding, who then released an inexpensive but unpolished game (and I'm very happy they did so). 

The KSPWheel mod linked above reworks the complex details of implementing wheels, including steering angle reduced at higher speed.

[jaunco325]

2 hours ago, OHara said:

When you are controlling the rover, the CapsLock key (on PC) turns the pitch/yaw/roll indicators blue.  When the indicators are blue, pressing W A S D (and I J K L if enabled) briefly moves the pitch/yaw/roll indicators from the center relatively slowly while the keys are pressed.  By tapping the keys, you can make small inputs.

Some things about 'precision mode' can be confusing.  The animations of some parts move just as fast whether precision-control mode is active, but the effect of W A S D is slowed.  It works when I J K L control wheels, even though the pitch/yaw/roll indicators do not move.  It does not work for some of the landing gear.

I get it. Thank You.

and thank you very much everyone for your help.