Electric power steering system

An electric power steering system comprising:

• a motor which is combined with a steering mechanism including a steering wheel, for producing a steering assist force when a vehicle is steered by means of the steering wheel;
• sensor means for detecting a moving state of the vehicle;
• drive means for driving said motor using a target control value based on a detection output from said sensor means;
• danger forecast means for forecasting danger which may be caused by the approach of an obstacle;
• and
• warning control means which cyclically fluctuates the target control value to cause vibration in said steering wheel when danger is forecasted by the danger forecast means.

A safety precaution device applicable to a steering system including a steering wheel for changing a travelling course of a vehicle comprising:

• obstacle detecting means for detecting the presence of an obstacle in the periphery of a vehicle;
• and
• means for causing vibration in said steering wheel if, when an obstacle has been detected by said obstacle detecting means, said steering wheel is turned to change the travelling course of the vehicle toward the obstacle thus detected;
• wherein said steering system includes a motor for producing a steering assist force when the steering wheel is turned;
• and
• wherein said means for causing vibration causes the motor to produce an intermittent counteractive force against turning of the steering wheel, thereby vibrating the steering wheel.