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This paper describes an autonomously controlled vehicles which is equipped with two sensing modes, one employing cameras and the other ultrasonic detectors. In either mode the vehicle can move smoothly, along a white line on the road(camera mode) or along a guard rail(ultrasonic mode), avoiding obstacles on straightaways and turning corners at intersections. In the camera mode, the vehicle can travel at 60km/h along a straight road.

An electronic engine control system that uses a microcomputer has been developed. It combines four control systems - fuel injection, ignition timing, EGR and idle speed control - utilizing the engine speed and intake air quantity for its main parameters. The control circuit is composed of an 8-bit microcomputer combining an 8k byte ROM, RAM, a custom designed input/output LSI, and two hybrid integrated circuits, one has voltage regulators and another has input/output interface circuits. The control program consists of a main program, a fail-safe program for noise protection and a check program for diagnostic functions. The main program uses interrupt techniques to control effectively the four items by one microcomputer. The interrupt requests occur from crankshaft position signal and interval timer signals.

A microcomputer control system for managing the automotive engine’s air-fuel ratio, spark ignition timing, exhaust gas recirculation and idle speed has been developed and is marketed in Japan under the name of ECCS. By installing this system in a 1,500 kg vehicle’s 6 cylinder 2.8 liter engine, the four factors listed above have been controlled so precisely that their optimum relative calibration has been realized. As a result, fuel economy has been improved by 10% while good drivability has been maintained. This paper outlines ECCS and describes how control factors in a “steady state” are determined. It also discusses the control sequence in transient conditions, such as “cold” starts, “hot” restarts, clutch engagement, acceleration, deceleration, gearshifts and the “warm-up” process.

An electronically controlled closed-loop carburetor system has been developed for production application in Datsun car models. Providing a means of complying with Japanese Emission Standards, this design features the electronic control of carburetor supplied fuel with significantly improved emission performance and fuel economy. Technological advances include the noteworthy compensation of oxygen sensor output variations and improved transient emission.