How to make an electric thruster?

[eberkain]

I am trying to make an rcs thruster to use underwater for docking. 

This is what I'm doing, but it doesn't work.  I'm thinking that maybe the module requires  a propellent that has mass?  

Spoiler

+PART[vernierEngine]:FOR[SimpleBallast]
{
    @name = aquaThruster
    @author = EberKain
    @TechRequired = start
    @category = Utility
    @title = EK-2 "Squirter" Aquatic Thruster 
    @description = 
    @tags = 

    @MODULE
    {
        @name = ModuleRCSFX
        @thrusterPower = 20
        @resourceName = ElectricCharge
        
        !PROPELLANT:HAS[#name[LiquidFuel]]{}
        !PROPELLANT:HAS[#name[Oxidizer]]{}
        PROPELLANT
        {
            name = ElectricCharge
            ratio = 1.0
            DrawGauge = True
        }
    
        !atmosphereCurve {}
        atmosphereCurve
        {
            key = 0 0.001
            key = 0.9 210
            key = 1 260
            key = 5 210
        }
    }    
}

 

This is what I see in the config cache, which looks ok to me.  

Spoiler

UrlConfig
{
    parentUrl = Squad/Parts/Engine/vernorEngine/vernorEngine.cfg
    PART
    {
        name = aquaThruster
        module = Part
        author = EberKain
        mesh = Vernier_Engine.mu
        scale = 1
        rescaleFactor = 2
        node_attach = 0.0, 0.0, 0.0, 1, 0, 0.0, 1
        TechRequired = start
        entryCost = 4200
        cost = 1400
        category = Utility
        subcategory = 0
        title = EK-2 "Squirter" Aquatic Thruster
        manufacturer = Reaction Systems Ltd
        description = 
        attachRules = 0,1,0,1,1
        mass = 0.08
        heatConductivity = 0.06
        skinInternalConductionMult = 4.0
        emissiveConstant = 0.8
        dragModelType = default
        maximum_drag = 0.01
        minimum_drag = 0.01
        angularDrag = 0.1
        crashTolerance = 50
        breakingForce = 50
        breakingTorque = 50
        maxTemp = 2000
        fuelCrossFeed = True
        PhysicsSignificance = 1
        bulkheadProfiles = srf
        tags = 
        EFFECTS
        {
            running
            {
                AUDIO
                {
                    channel = Ship
                    clip = sound_rocket_mini
                    volume = 0.0 0.0
                    volume = 0.1 0.0
                    volume = 0.5 0.05
                    volume = 1.0 0.5
                    pitch = 0.0 0.5
                    pitch = 1.0 1.0
                    loop = true
                }
                MODEL_MULTI_PARTICLE
                {
                    modelName = Squad/FX/Monoprop_medium
                    transformName = RCSthruster
                    emission = 0.0 0.0
                    emission = 0.1 0.0
                    emission = 1.0 1.0
                    speed = 0.0 0.8
                    speed = 1.0 1.0
                    localRotation = -90, 0, 0
                }
            }
        }
        MODULE
        {
            name = ModuleRCSFX
            stagingEnabled = False
            thrusterTransformName = RCSthruster
            thrusterPower = 20
            resourceName = ElectricCharge
            resourceFlowMode = STAGE_PRIORITY_FLOW
            runningEffectName = running
            plumeToKeep = running
            PROPELLANT
            {
                name = ElectricCharge
                ratio = 1.0
                DrawGauge = True
            }
            atmosphereCurve
            {
                key = 0 0.001
                key = 0.9 210
                key = 1 260
                key = 5 210
            }
        }
        MODULE
        {
            name = HotSpotModule
        }
    }
}

It is duplicated in the config cache, but so is vernierEngine.  It looks like Squad has two stock configs that both use the same part name. 

 \GameData\Squad\Parts\Engine\vernorEngine

\GameData\Squad\Parts\Utility\linearVernorRCS

 

[TythosEternal]

On 12/20/2020 at 10:17 AM, eberkain said:

This is what I'm doing, but it doesn't work

1. What happens when you attempt to activate the component?
2. Would you be willing to upload your part mod to something like GitHub where we could test it out and give you feedback?

[wasml]

You might consider using water as an alternate propellant and adding an intake that collects water - the ModuleResourceIntake even has a "underwaterOnly" field. Downside would be the need to either add the resource yourself or have a dependency on Community Resource Pack.

Edited December 25, 2020 by wasml
spelling

[JadeOfMaar]

You'll want to use a propellant that has mass, yes. Anything that produces thrust in KSP needs some amount of mass to use in its calculations. And it would be best to use the IntakeLqd resource that's provided by CRP. It's not guaranteed that every ocean has water and a thruster in this situation won't care what it's pushing out to move the ship.