RCS¶
Some of the Parts returned by LIST PARTS will be of type RCS. It is also possible to get just the RCS parts by executing LIST RCS, for example:
LIST RCS IN myVariable.
FOR rcs IN myVariable {
print "An rcs thruster exists with ISP = " + rcs:ISP.
}.
- structure RCS¶
Suffix
Type (units)
Description
All suffixes of
PartIs this thruster enabled.
Is yaw control enabled for this thruster.
Is pitch control enabled for this thruster.
Is roll control enabled for this thruster.
Is fore/aft control enabled for this thruster.
Is port/starboard control enabled for this thruster.
Is dorsal/ventral control enabled for this thruster.
Does this thruster apply fore thrust when the ship throttled up.
Does this thruster always apply full thrust.
Scalar(%)Tweaked thrust limit.
The game’s built-in RCS input null zone for this RCS thruster.
Scalar(kN)Untweaked thrust limit.
Scalar(kN)Max thrust at the specified pressure (in standard Kerbin atmospheres).
Scalar(kN)Available thrust at full throttle accounting for thrust limiter.
Scalar(kN)Available thrust at the specified pressure (in standard Kerbin atmospheres).
Scalar(unit/s)Untweaked maximum volumetric flow rate of fuel at full throttle.
Scalar(Mg/s)Untweaked maximum mass flow rate of fuel at full throttle.
Specific impulse at the given pressure (in standard Kerbin atmospheres).
Vacuum specific impulse
Synonym for VACUUMISP
Specific impulse at Kerbin sealevel
Synonym for SEALEVELISP
Check if no more fuel.
List of thrust
Vectorsfor this RCS module.Lexicon of resources consumed by this thruster, keyed by resource name.
- RCS:STARBOARDENABLED¶
- Access
Get/Set
- Type
Is port/starboard control enabled for this rcs thruster.
- RCS:TOPENABLED¶
- Access
Get/Set
- Type
Is dorsal/ventral control enabled for this rcs thruster.
- RCS:FOREBYTHROTTLE¶
- Access
Get/Set
- Type
Does this thruster apply fore thrust when the ship throttled up.
- RCS:THRUSTLIMIT¶
- Access
Get/Set
- Type
Scalar(%)
If this is a thruster with a thrust limiter (tweakable) enabled, what percentage is it limited to? Note that this is expressed as a percentage, not a simple 0..1 coefficient. e.g. To set thrustlimit to half, you use a value of 50.0, not 0.5.
This value is not allowed to go outside the range [0..100]. If you attempt to do so, it will be clamped down into the allowed range.
Note that although a kerboscript is allowed to set the value to a very precise number (for example 10.5123), the stock in-game display widget that pops up when you right-click the rcs will automatically round it to the nearest 0.5 whenever you open the panel. So if you do something like
set ship:part[20]:thrustlimit to 10.5123.in your script, then look at the rightclick menu for the rcs, the very act of just looking at the menu will cause it to become 10.5 instead of 10.5123. There isn’t much that kOS can do to change this. It’s a user interface decision baked into the stock game.
- RCS:DEADBAND¶
- Access
Get/Set (but Note the Warning on SET below)
- Type
Default: 0.05.
Please note the warning below before you try to SET this.
The stock game imposes a large dead zone on RCS thrusters. By default they will not respond to any inputs less than this value. For example, at the default value of 0.05, the RCS thruster will ignore this statement:
set ship:control:yaw to 0.049.
but it will respond to this statement:
set ship:control:yaw to 0.051.
The reason this limit exists is apparently (this is speculation, warning) that it’s how the stock game prevents SAS from spending a lot of monopropellant when it wiggles the controls small amounts. When control inputs are smaller than this value, then the RCS thrusters ignore them and only the reaction wheels and engine gimbals respond. Despite the fact that this is really only a problem with SAS, the game appears to have solved the problem by imposing this null zone physically on the RCS parts themselves so the limit affects everything that uses them, including kOS autopiloting and user manual control.
The best way to deal with this, if you have a script that wants the RCS thrusters to operate at a value less than this, is to pulse the input intermittently on and off at 0.05 to achieve amounts smaller than 0.05, rather than trying to solve it by setting this value. (Remember that in the real world, thrusters have a minimum thrust they can’t go below so it’s not entirely unrealistic for this deadband to exist in the game.)
Warning
BEWARE if you want to Set this: Although this can be set and changing it works okay in the current version of KSP as of this writing (KSP 1.10.1), it is exactly the sort of thing that seems could break in future versions of KSP.
Be aware of that when deciding to change it. (If you are a programmer,
you might understand the next sentence and get a clear picture of
why this warning is here: The value in the KSP class that this
affects is marked private and kOS is using “Reflection” to bypass
that access rule.)
If you are tempted to change this value, please first consider coming up with a solution where your script pulses the input on and off between 0.05 and 0 to simulate inputs less than 0.05.
Warning
BEWARE if you want to Set this: Setting this value too small on your RCS thrusters will cause the stock SAS to wastefully spend RCS propellant wiggling the controls when it tries to hold position. (If you ever played KSP back in its alpha pre-release days you might remember SAS behaving like this in the old days.)
- RCS:MAXTHRUST¶
- Access
Get only
- Type
Scalar(kN)
How much thrust would this rcs thruster give at its current atmospheric pressure if one of the control axes that activates it (yaw, pitch, roll, fore, aft, or top) was maxxed, and the thrust limiter was max at 100%. Note this might not be the thruster’s actual max thrust it could have under other air pressure conditions. Some thrusters have a very different value for MAXTHRUST in vacuum as opposed to at sea level pressure.
- RCS:MAXTHRUSTAT(pressure)¶
- Parameters
pressure – atmospheric pressure (in standard Kerbin atmospheres)
- Return type
Scalar(kN)
How much thrust would this rcs thruster give if one of the control axes that activated it (yaw, pitch, roll, fore, aft, or top) was maxxed and thrust limiter was max at the given atmospheric pressure. Use a pressure of 0.0 for vacuum, and 1.0 for sea level (on Kerbin) (or more than 1 for thicker atmospheres like on Eve). (Pressure must be greater than or equal to zero. If you pass in a negative value, it will be treated as if you had given a zero instead.)
- RCS:THRUST¶
- Access
Get only
- Type
Scalar(kN)
How much thrust is this rcs thruster is giving at this very moment.
- RCS:AVAILABLETHRUST¶
- Access
Get only
- Type
Scalar(kN)
Taking into account the thrust limiter tweakable setting, how much thrust would this rcs thruster give at its current thrust limit setting and atmospheric pressure conditions, if one of the control axes that activated it (yaw, pitch, roll, fore, aft, or top) was maxxed .
- RCS:AVAILABLETHRUSTAT(pressure)¶
- Parameters
pressure – atmospheric pressure (in standard Kerbin atmospheres)
- Return type
Scalar(kN)
Taking into account the thrust limiter tweakable setting, how much thrust at the given atmospheric pressure would this rcs thruster give at its current thrust limit setting if one of the control axes that activated it (yaw, pitch, roll, fore, aft, or top) was maxxed. The pressure is measured in ATMs, meaning 0.0 is a vacuum, 1.0 is sea level at Kerbin. (Pressure must be greater than or equal to zero. If you pass in a negative value, it will be treated as if you had given a zero instead.)
- RCS:MAXFUELFLOW¶
- Access
Get only
- Type
Scalar(units/s)
How much fuel volume would this rcs thruster consume at standard pressure and velocity if one of the control axes that activated it (yaw, pitch, roll, fore, aft, or top) was maxxed, and the thrust limiter was max at 100%. Note this might not be the engine’s actual max fuel flow it could have under other air pressure conditions.
- RCS:MAXMASSFLOW¶
- Access
Get only
- Type
Scalar(Mg/s)
How much fuel mass would this rcs thruster consume at standard pressure and velocity if one of the control axes that activated it (yaw, pitch, roll, fore, aft, or top) was maxxed, and the thrust limiter was max at 100%. Note this might not be the engine’s actual max fuel flow it could have under other air pressure conditions.
- RCS:ISP¶
- Access
Get only
- Type
- RCS:ISPAT(pressure)¶
- Parameters
pressure – atmospheric pressure (in standard Kerbin atmospheres)
- Return type
Specific impulse at the given atmospheric pressure. Use a pressure of 0 for vacuum, and 1 for sea level (on Kerbin). (Pressure must be greater than or equal to zero. If you pass in a negative value, it will be treated as if you had given a zero instead.)
- RCS:VACUUMISP¶
- Access
Get only
- Type
Vacuum specific impulse
- RCS:SEALEVELISP¶
- Access
Get only
- Type
Specific impulse at Kerbin sealevel.
- RCS:FLAMEOUT¶
- Access
Get only
- Type
Is this rcs thruster failed because it is starved of a resource (monopropellant)?
- RCS:THRUSTVECTORS¶
-
This gives a list of all the vectors that this RCS module can thrust along. Vectors returned are of unit length. The vectors are returned in Ship-Raw coordinates, rather than relative to the ship. (i.e. if it thrusts along the ship’s fore axis, and the ship’s current
ship:facing:forevectorisV(0.7071, 0.7071, 0), then the value this returns would beV(0.7071, 0.7071, 0), notV(0,0,1)).
- RCS:CONSUMEDRESOURCES¶
- Access
Get only
- Type
This gives a lexicon of all the resources this rcs thruster consumes, keyed by resource name.