Steering control system for use in a track-laying vehicle

A steering control system for use in a track-laying vehicle comprising:

• (a) a rotary power source;
• (b) a steering motor driven by the rotation of the power source for driving crawler belts provided at both sides of the vehicle such that a relative travel difference results between the crawler belts, thereby turning the vehicle rightwards or leftwards;
• (c) steering instructing means which can be displaced from a neutral position by operation and which instructs, according to the direction and distance of the displacement of the steering instructing means, a turning direction and a turning radius for the vehicle, the turning radius decreasing as the displacement distance increases;
• (d) displacement detector means for detecting the displacement of the steering instructing means;
• and
• (e) steering motor revolution speed control means for obtaining a target steering motor revolution speed which is made proportional to the revolution speed of the power source based on the displacement of the steering instructing means detected by the displacement detector means and controlling the revolution speed of the steering motor with the target steering motor revolution speed.