Heavy rovers and gravity?

[strider3]

How would you guys go about increasing the "power" of a heavy rover? I have a "fuel rover" landed on Duna but it is very weak and can't make it up mild inclines. I used this same model on Minmus but that is "apples to pineapples" (forget oranges) when compared to Duna. Maybe extra sets of rover wheels? Here's a picture of the original, Minmus, model. Only difference is added parachutes for landing on Duna and removal of the ventral engines in exchange for a buttload of Twitches on the girders:

Here is the Duna version landing:

 

[bewing]

Well, the giant wheels have a whole lot of power.

If you have ISRU on the CB of your choice, then adding some rocket boost for climbing hills is always fun.

 

[Gargamel]

3 hours ago, bewing said:

Well, the giant wheels have a whole lot of power.

That's an understatement.   Simple speed tests of 4-6 wheeled rovers can hit very very high speeds.   They work in a different fashion than the rest of the wheels.

You can add more wheels to your rover, and that will increase power, but there's a downside.   KSP doesn't have any stock hinges or bearings, so large sets of wheels have trouble making the transitions between different angles of slopes, as it won't conform to the terrain.   At the bottom of a hill, only your front and rear sets of wheels will actually be touching the ground, which can lead to an under-power scenario again.   So you sometimes need to have a bit of momentum when approaching hills.  But not too fast, cause you can break the wheels. 

[strider3]

By "giant wheels" I'm assuming your talking about the RoveMax XL3's?

I also wonder about steering a vehicle with many sets of wheels...will the turning radius be affected?

Will the mass of my fuel rover affect the power? IOW, will my empty rover go better than if it was full of fuel?

Edited January 26, 2019 by strider3

[Gargamel]

31 minutes ago, Victor3 said:

I also wonder about steering a vehicle with many sets of wheels...will the turning radius be affected?

When I mentioned they work in a different fashion, I mean they work more like tank treads than wheels that turn to steer.   So if you turn right, the wheels on the right spin backwards, while the ones on the left spin forward.   Zero turn radius with practice.    And you quickly learn that by pushing forwards, and quickly tapping left and right, you can achieve some insane speeds. 

[bewing]

58 minutes ago, Victor3 said:

By "giant wheels" I'm assuming your talking about the RoveMax XL3's?

Yup, I call them the "Mondo" wheels.

58 minutes ago, Victor3 said:

I also wonder about steering a vehicle with many sets of wheels...will the turning radius be affected?

Yes, with many wheels on a rover, they turn funny. You can minimize that by putting them in groups, or clipping them together. 4 wheels at the front, 4 wheels at the back. Spreading them out evenly causes the most issues.

58 minutes ago, Victor3 said:

Will the mass of my fuel rover affect the power? IOW, will my empty rover go better than if it was full of fuel?

Yes, the wheels have a strict limit on their power level, based on model. All those small wheels are really made for low mass rovers. Put them on a high mass rover, and it'll have trouble accelerating or climbing or stopping. But sometimes rovers don't need to be built to accelerate or climb or stop.

[strider3]

4 minutes ago, bewing said:

Yes, the wheels have a strict limit on their power level, based on model. All those small wheels are really made for low mass rovers. Put them on a high mass rover, and it'll have trouble accelerating or climbing or stopping. But sometimes rovers don't need to be built to accelerate or climb or stop.

I'll have to make sure my fuel hauler lands downhill from my fuel rover, LOL! That way I return to the mining colony uphill...and empty!

[Gargamel]

22 hours ago, Gargamel said:

When I mentioned they work in a different fashion, I mean they work more like tank treads than wheels that turn to steer.   So if you turn right, the wheels on the right spin backwards, while the ones on the left spin forward.   Zero turn radius with practice.    And you quickly learn that by pushing forwards, and quickly tapping left and right, you can achieve some insane speeds. 

Oops... when I posted that, I was referring to the XL3's.   What @bewing said. 

[Fearless Son]

I noticed that you had a bunch of RCS nozzles on the bottom of the rover.  Do you have similar nozzles on the top?  

This may be a marginal in Duna's gravity, but I have noticed that increasing the down force on the wheels helps translate more of their power to locomotion for the rover.  So if you have some upward-thrusting capacity on the rover, you can temporarily activate that to push the rover more firmly into the ground, which will result in more greater wheel traction and help it climb slopes a little easier.

[Rocket In My Pocket]

If hill climbing is the specific problem, try mucking with the wheel options in the right click menu.

Increasing friction and playing with traction control could help you crawl your way up the incline.

[KerikBalm]

On 1/26/2019 at 1:42 AM, Gargamel said:

Zero turn radius with practice.    And you quickly learn that by pushing forwards, and quickly tapping left and right, you can achieve some insane speeds. 

^This^ Those wheels often get dumped on so much because of their high mass and low displayed top speed... but they are soo good for rovers.... nearly unbreakable, you can be careening over the terrain at 100 m/s with a stable design, and the turning radius is great.

The only downside is that they are big, and I can't make a design that uses them that can be deployed and recovered from a mk3 cargobay.

Having skycranes pick them up and drop them off is pretty difficult to line up with docking ports, or even appropriate claws

[Gargamel]

13 hours ago, KerikBalm said:

Having skycranes pick them up and drop them off is pretty difficult to line up with docking ports, or even appropriate claws

They're great with KIS games though, just plug in a hose and you're connected.   And yeah, they're so big, and the rovers they support make them even bigger, They're a real pain to get into space sometimes.