Gravity Field

gravityField = NoGravityField()

Generate an instance of type NoGravityField that defines no gravity.

UniformGravityField(; g = 9.81,
                      n = [0,-1,0])

Generate an instance of type UniformGravityField that defines a uniform gravity field with gravitational acceleration g in direction n. The default value is a gravity of 9.81 m/s^2 in negative direction of the y-axis of the root (world) Object3D.

Arguments

• g::Float64: Gravitational acceleration in m/s^2.
• n::AbstractVector: Direction of gravitational acceleration

Example

using Modia3D

grav = UniformGravityField()
   r = Modia3D.EarthRadius
   g = gravityAcceleration(grav,r)  # g is independent of r

PointGravityField([mass|; mue = G*EarthMass])

Generate an instance of type PointGravityField that defines a point gravity field of mass or gravity field constant mue. The gravity center is located at the world origin, i.e. the gravitational acceleration decreases quadratically with distance from world.

Example

using Modia3D

grav = PointGravityField()   # Gravity field of earth
   r = Modia3D.EarthRadius
   g = gravityAcceleration(grav,r)  # g is a function of r.