I cant for the life of me tune this PID controller, Please Help!

Help and Feedback Scripting Support
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#1

I’ve been trying for the past 2 days to figure out a way to make this PID controller stabilize a hovering vehicle using a vectorForce. I just simply cant figure out the correct PID gains, its either oscillating intensely or not moving at all. But no matter what gains I put, it NEVER stabilizes at the height I’m trying to get it to hover at.

–Notes:

  • Everything is done in a local script while using RenderStepped.
  • I have workspace gravity set to 0, as I am applying gravity directly in the script on the vehicle.
  • I am using @BRicey763 RoPID Module: RoPID: PID Control in Roblox!
  • The vehicle is only one part with its “Massless” property turned on

Here is the script responsible for calculating all the forces.
–Variables:

  • GlobalVehicleSettings.HoverHeight = 15
  • GlobalVehicleSettings.RayLength = 50
  • GlobalVehicleSettings.HoverForce = 300
  • GlobalVehicleSettings.HoverGravity = 200
  • GlobalVehicleSettings.FallGravity = 800
--Function to calculate the vehicles Hover
local function CalculateHover(dt)
	--Shoot a ray to check if the vehicle is on the ground
	local HoverRay = workspace:Raycast(MainVehicleInfo.CenterVectorAtt.WorldPosition,(MainVehicleInfo.CenterVectorAtt.WorldCFrame.UpVector*-1)*GlobalVehicleSettings.RayLength)
	
	--Local Vars
	local GroundNormal
	
	--If the raycast hits and the ship is on the ground
	if HoverRay then
		--Save the rayinfo in local vars for better readability
		local Height = HoverRay.Distance
		GroundNormal = HoverRay.Normal
		
		--Calculate the hover force using Briceys RoPID module
		local ForcePercent = MainVehicleInfo.PIDController:Calculate(GlobalVehicleSettings.HoverHeight,Height,dt)
Base.Position+MainVehicle.VehicleBase.CFrame.UpVector*ForcePercent)
		--print(ForcePercent)
		
		--Calulate the total hover force vector required based on the normal of the raycast
		local Force = GroundNormal * ForcePercent * GlobalVehicleSettings.HoverForce 
		
		--Calculate the gravity relative to the ships CFrame
		local Gravity = -GroundNormal * GlobalVehicleSettings.HoverGravity * Height
		
		--Apply the force to the VectorForce of the vehicle
		MainVehicleInfo.CenterVectorAtt.VectorForce.Force += Force
		MainVehicleInfo.CenterVectorAtt.VectorForce.Force += Gravity
		
	else --If the vehicle is not on the ground
		--The normal used is the global up vector
		GroundNormal = Vector3.new(0,1,0)
		
		--Calculating and applying gravity
		local Gravity = -GroundNormal*GlobalVehicleSettings.FallGravity
		MainVehicleInfo.CenterVectorAtt.VectorForce.Force += Gravity
	end
end

Here is what the current PID gains are and what it looks like
image


(“LineA” and the moving red line on the part are just representations of the ForcePercent Value from the script above)

Any help on how to stabilize the vectorForce is greatly appreciated, Thanks!