Hardware-in-the-Loop (HIL) applications are used by design and test engineers to evaluate and validate vehicle components during development of new systems, assemblies and vehicles. Rather than testing these components in complete system setups, HIL allows the testing of new components and prototypes while communicating with software models that simulate the rest of the vehicle and system

1 : a screen of wood or leather placed on the forepart of a horse-drawn carriage, sleigh, or other vehicle to intercept water, mud, or snow thrown up by the heels of the horses

1 : a screen of wood or leather placed on the forepart of a horse-drawn carriage, sleigh, or other vehicle to intercept water, mud, or snow thrown up by the heels of the horses