2 Joint 2 Limb Inverse Kinematics

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#27

So I am very unfamiliar with IK, however, I am getting a grasp. How would I go about adding another limb?

This is the only code I changed and it works fine except the goal part is at the joint I do not want it to be at. How do I fix this?

Code:

local workspace		= game:GetService("Workspace")
local storage		= game:GetService("ReplicatedStorage")
local runService	= game:GetService("RunService")

local goalPart		= workspace:WaitForChild("GoalPosition")
local shoulderPart	= workspace:WaitForChild("ShoulderPosition")
local upperArm		= workspace:WaitForChild("UpperArm")
local lowerArm		= workspace:WaitForChild("LowerArm")
local grapple = workspace:WaitForChild("Grapple")

local solveModule	= storage:WaitForChild("SolveIK")
local solveIK		= require(solveModule)

----

local SHOULDER_OFFSET		= CFrame.new(1.5, 0.5, 0)
local VECTOR3_UP			= Vector3.new(0, 1, 0)

----

runService.Heartbeat:Connect(function()
	local shoulderCFrame = shoulderPart.CFrame * SHOULDER_OFFSET
	local goalPosition = goalPart.Position	
	
	local upperV3 = VECTOR3_UP * upperArm.Size
	local lowerV3 = VECTOR3_UP * lowerArm.Size
	local grappleV3 = VECTOR3_UP * grapple.Size

	local planeCF, shoulderAngle, elbowAngle, otherelbow = solveIK(shoulderCFrame, goalPosition, upperV3.Y, lowerV3.Y, grappleV3.Y)
	local shoulderAngleCFrame = CFrame.Angles(shoulderAngle, 0, 0)
	local elbowAngleAngleCFrame = CFrame.Angles(elbowAngle, 0, 0)

	upperArm.CFrame = planeCF * shoulderAngleCFrame * CFrame.new(-upperV3 * 0.5)
	lowerArm.CFrame = upperArm.CFrame * CFrame.new(-upperV3 * 0.5) * elbowAngleAngleCFrame * CFrame.new(-lowerV3 * 0.5)
	grapple.CFrame = lowerArm.CFrame * CFrame.new(-upperV3 * 0.5) * elbowAngleAngleCFrame * CFrame.new(-lowerV3 * 0.5)

end)

Thanks!

#28

How would I make this R6 Because I Donā€™t Really See Many Posts?

#30

It isnā€™t bad, itā€™s just older.

#31

What am I supposed to do in this situation?

What do i do in this situation
What do i do in this situation736Ɨ785 272 KB

#32

What is the issue, you gotta give context instead of just showing an image and saying ā€œWhat am I supposed to do in this situation?ā€

#33

Sorry, Iā€™ve fixed the issue. I had a scripted animation playing.

#35

Sorry for the bump!

Has anyone applied this to the module? I canā€™t seem to figure out where/how to apply this, testing this on a 2.0 rig is accurate enough as it is but when I test this using the woman package the arms are way off target (potentially also due to the elbow offset?)

#36

This looks useful, and I was actually looking for inverse kinematic tutorials. But Iā€™m still unsure about how to use it for walking in where you put the script wise or if this is even for walking. This kinda went over my head so I canā€™t really figure out how to use it with walking.

I might just change names or something, iā€™m also not sure if this is only for animations instead of actual walking (For an fps game a couple friends and i are working on).

How do I use this for walking? (Or if its already for walking just tell me I donā€™t really know how this works)

#37

The function provided cannot be run as it errors at :pointToObjectSpace(), the error it provides is
image
For the originCF im passing through a cframe, for the targetPos im passing through a position.

Iā€™m incredibly confused any help is appreciated.

Edit: my bad i was doing something wrong

#38

Is there anyway I could apply this to 3 joints (upper arm, lower arm, hand)?

#39

Youtube has got ya covered :wink:

#40

Sadly it doesnā€™t Iā€™ve tried said method multiple times to no luck. Iā€™ve covered the internet trying to find a solution yet cannot.

#41

might be a little off topic but, why do make a variable for VECTOR3_UP instead of Vector.yAxis? Same goes for any other use youā€™ve given it

#42

The release of vector.yAxis is on 2021 and the tutorial is on 2019.

Also localizing your variables is always preferred for minor optimization rather than indexing it from a table using the dot notation

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