This paper describes an easily-installed, programmable, battery-powered, “series servo second steering wheel”. The steering machine is designed to execute any 16384-step steering program with force and velocity capabilities significantly greater than those of the human driver. Its EPROM memory contains sixteen separate programs, which can be programmed to duplicate any steering input with fidelity and repeatability. During the execution of a program, the handwheel is mechanically “grounded” to eliminate driver interference with measurement of steering angles and torques. The program also outputs auxiliary signals that can be used to control vehicle throttle and brakes, data recorders, or other devices.The paper describes the steering machine's design and operation, its measured capabilities, and some of the SAE, ISO, and rollover test protocols for which it is designed.