Wheels

From left to right, the RoveMax Model XL3, the TR-2L Ruggedized Vehicular Wheel, the RoveMax Model M1, and the RoveMax Model S2. Kerbal and command pod for scale.

Wheels are used to make a ground vehicle move. Unlike landing gear, wheels have built-in electric motors; by using electric charge, they can drive themselves. They are frequently used in rovers.

List of Wheels

Image	Part	Radial size	Cost ()	Mass (t)	Max. Temp. (K)	Tolerance (m/s)	Tolerance (g)	Electricity (⚡/s)	Max. Motor Speed (m/s)	Brake Torque (kNm)
	RoveMax Model S2	Radial mounted	300	0.05	1 200	20	20	1.0	12	0.34
	RoveMax Model M1	Radial mounted	450	0.075	1 200	50	50	2.5	34	2
	TR-2L Ruggedized Vehicular Wheel	Radial mounted	760	0.105	1 200	100	80	3.5	58	3
	RoveMax Model XL3	Radial mounted	1 200	1.25	1 200	150	200	5.0	15.5	30

Usage

The four models of wheels differ in size, which affects their top speed, electricity consumption, and max load. Larger wheels tend to have a greater top speed, higher electricity consumption, and a greater max load.

If a wheel is subject to high enough stress, it can "break". This form of breakage is similar to solar panels, where the wheel will cease to function. Additionally, a broken wheel will display a "broken" texture and say "Broken: Repair from EVA" in the wheel's PAW. Among other causes, wheels can break when their max load is exceeded (often seen on Eve rovers), or when the vehicle lands hard on its wheels. The stress on a wheel can be monitored in the right-click menu, under "Wheel Stress". (Note that this stress-driven breakage is different from breaking on impact - if a wheel hits the ground hard enough to exceed the impact tolerance, it will explode and disappear.)

Broken wheels can be repaired by an Engineer, using EVA Repair Kits depending on the wheel's size: for example, a RoveMax Model S2 will require 1 kit to repair, while a RoveMax Model XL3 will require 4 kits. (Prior to 1.11, wheels could be fixed by Engineers for free, as long as said Engineer was level 3 or higher.)

Wheels also feature traction control and friction control. By default these options are set to Auto with a traction control value of 1.0. The traction control value can be tailored to individual vehicles to prevent wheelspin in different conditions. Traction control can be overridden and a manual limit to the motor output set. Friction control can be overridden and adjusted on a scale from 0.1-5.0. Friction control determines the responsiveness of the wheels with the ground. Low values will have a lot of slip, so the vehicle will slide or drift. High values will have better traction but may make the vehicle more susceptible to rolling over.

Wheel settings

By opening a wheel's right-click menu, the player can find many settings, such as:

• "Steering" - whether the wheels will rotate in order to steer the vehicle.

• The RoveMax Model XL3 does not rotate, and instead uses differential steering to change direction. Its menu will show a "Diff Steering" to reflect this.

• "Steering: Direction" - when switched from "Normal" to "Inverted", the wheel will attempt to steer in the opposite direction. This can be useful when the game attempts to turn a wheel the wrong way.
• "Motor" - whether the wheel's motor is enabled. Disabling a motor will reduce electricity consumption, at the cost of... less motors.
• "Motor: Direction - when switched from "Normal" to "Inverted", the wheel will rotate in the opposite direction.
• "Friction Control" - when switched from "Auto" to "Override", the player can adjust the wheel's friction.

• When set to manual, an additional bar (also labeled "Friction Control") appears, allowing friction to be adjusted from 0.1 to 5.0.

• "Spring/Damper" - when switched from "Auto" to "Override", the player can adjust the suspension on the wheel.

• When set to manual, two additional bars appear:

• "Spring Strength": higher values make the spring stronger, making it push the vehicle up harder.
• "Damper Strength": higher values result in greater dampening, making the vehicle less bouncy.

• "Traction Control - toggling this setting will switch between the two traction control modes.

• When set to "Auto", a "Traction Control" bar will appear.
• When set to "Override", a "Drive Limiter" bar will instead appear. This controls the motor's power cap - a drive limiter of 100% results in the motor using 100% of its power, while a limiter of 0% results in the motor staying at 0% of its power.

• "Brakes" - this bar lets the player adjust brake strength.

Additionally, two informational bars are available:

• "Motor" - shows the motor's current power output, on a scale from 0 to 100.
• "Wheel Stress" - shows the load on the wheels. If the load is too high, the wheels will break.

Tweaking wheel settings to improve Vehicle Stability

• Divide the wheels into steering-enabled (traditionally front) and steering-disabled (traditionally rear).
• Use low friction control on the steering wheels, this will allow them to slip instead of attempting to oversteer the vehicle.
• Use high friction control on non-steering wheels, this will cause the vehicle to want to go in a straight line and resist changing direction.

This scheme will improve stability when driving at high speed on flat ground. Beware that it will not help much on uneven terrain.