Abstract: To maintain a suitable vehicle separation between a driven vehicle and a preceding vehicle, a controller predicts a closest approach distance between the driven vehicle and the preceding vehicle on the assumption that the preceding vehicle decelerates at a deceleration detected by a sensor and that the driven vehicle decelerates at a prescribed assumed deceleration after running at a speed detected by the vehicle speed sensor for an idle running time. The controller predicts the speed at the time of closest approach when the separation between the preceding vehicle and the driven vehicle is the closest approach distance. A suitable vehicle separation is determined based on the predicted speed at the time of closest approach and a previously set length of time, and when the predicted closest approach distance is smaller than the suitable vehicle separation, a warning or braking force is generated.

Abstract: In order to maintain a suitable vehicle separation between a driven vehicle with respect to a preceding vehicle, an electric controller 10 predicts a closest approach distance between the driven vehicle and the preceding vehicle on the assumption that the preceding vehicle decelerates at a deceleration detected by a vehicle separation sensor 12 and the like and that the driven vehicle decelerates at a prescribed assumed deceleration after running at a speed detected by the vehicle speed sensor 11 for an idle running time. The electric controller predicts the speed at the time of closest approach when the separation between the preceding vehicle and the driven vehicle is the closest approach distance.

Abstract: Warning apparatus for an automotive vehicle, operable to generate a warning signal when a distance between the vehicle and an object in front of the vehicle is shorter than a predetermined threshold value, the apparatus including a characteristic-value storage portion which stores at least one characteristic-value relationship between at least two of a plurality of brake operating characteristic values relating to a braking operation by an operator of the vehicle to brake the vehicle, and a threshold-value determining portion operable to determine the threshold value of the distance, on the basis of at least one of an estimated braking state of the vehicle estimated on the basis of the characteristic-value relationship stored in the characteristic-value storage portion, a running-state quantity indicative of a running state of the vehicle, and a moving-state quantity indicative of a moving state of the object.

Abstract: Warning apparatus for an automotive vehicle, operable to generate a warning signal when a distance between the vehicle and an object in front of the vehicle is shorter than a predetermined threshold value, the apparatus including a characteristic-value storage portion which stores at least one characteristic-value relationship between at least two of a plurality of brake operating characteristic values relating to a braking operation by an operator of the vehicle to brake the vehicle, and a threshold-value determining portion operable to determine the threshold value of the distance, on the basis of at least one of an estimated braking state of the vehicle estimated on the basis of the characteristic-value relationship stored in the characteristic-value storage portion, a running-state quantity indicative of a running state of the vehicle, and a moving-state quantity indicative of a moving state of the object.

Abstract: An ultrasonic measuring system detecting state informations of a vehicle other than a vehicle speed. An ultrasonic transducer TR1 directly detects the vehicle speed. A second ultrasonic transducer and a third ultrasonic transducer are disposed respectively in front of and at a back of a rotational center of the vehicle and separated from each other at a predetermined distance. They respectively transmit ultrasonic waves at right angles to the running direction of the vehicle and respectively at second and third predefined down-angles relative to the road. A two-dimensional speed of the vehicle can be measured on the basis of the speeds obtained by the transducers TR2 and TR3.

Abstract: An ultrasonic measuring system for a vehicle is composed of first and second ultrasonic transducing assemblies TR1 and TR2. Each transducing assembly TR1, TR2 has three ultrasonic transducers TR11, TR12, TR13, TR21, TR22, TR23 which are separated from each other at an angle of 120 degrees in a horizontal plane about axis disposed at a front and a rear of the vehicle, respectively. Each transducer transmits ultrasonic waves to a road surface at a predefined down-angle relative to the road surface and receives reflected waves from the road surface. Each of the transducers TR21, TR22, TR23 transmits ultrasonic waves to the road surface and receiving reflected waves from the road surface in an opposite direction to a corresponding one of the transducers TR11, TR12, TR13.

Abstract: There are disclosed an apparatus and a method for searching for the optimum route to be followed by a vehicle. The apparatus comprises a memory storing road maps, a keyboard having keys, and a microcomputer. The driver of the vehicle specifies a starting point and a destination in a network of roads displayed on a color CRT. Then, the microcomputer searches the network for a route which connects the starting point to the destination at the shortest distance.