A steering robot for attachment to a vehicle's steering wheel has its own steering wheel attached to a rotor of an annular motor. The latter has a stator. Fitted to the forward (in use) side of rotor is an annular mounting plate, having three tabs extending slightly inwards for receiving mounting bolts. A clamp formed of a ring having equally spaced around it three slotted radial lugs. The lugs provide attachments for three clamping fixtures, by means of which the clamp can be attached temporarily to the vehicle's steering wheel. The stator has a pair of torque reaction lugs via which steering torque exerted by the motor to effect a steering maneuver under test or investigation can be reacted. The steering robot is open-centered, whereby steering wheel mounted controls can be operated normally.