local velocityToAdd = platformVelocity

local humanoid = character:FindFirstChildOfClass("Humanoid")
local isGrounded = humanoid and humanoid.FloorMaterial ~= Enum.Material.Air

if not isGrounded then
    -- Remove Y component while jumping/falling
    velocityToAdd = Vector3.new(platformVelocity.X, 0, platformVelocity.Z)
end

hrp.AssemblyLinearVelocity += velocityToAdd