Loads & drive laws

Gravity is a force that's always on, at a fixed value. A Force or Torque load lets you place a push (or twist) anywhere, aim it, and decide exactly how its size changes over time. Every load in BriskFyr is built the same way:

load(t) = magnitude × drive(t)

The drive law is the time-shape — a dropdown on any Force, Torque, or joint drive:

• Constant — always the same value.
• Step — off, then instantly on at a chosen time.
• Ramp — grows steadily from a start time.
• Sine / Cosine — oscillates at a chosen frequency.
• Linear — changes at a steady rate from a starting value.
• Piecewise linear — a hand-specified sequence of (time, value) points.

For a free body — no joint soaking anything up — Newton's second law applies directly to whatever you dial in:

linear: a = F / m · rotational: α = τ / I

Everything you apply shows up as acceleration; nothing is being absorbed by a constraint.

Try Constant, Step and Ramp in Tutorial 5 — Forces, Torques & Drive Laws