Engine testing apparatus and map preparing method for an engine testing apparatus/vehicle testing apparatus

Abstract

The present invention provides a map preparing method for an engine testing apparatus or a vehicle testing apparatus capable of preventing a peculiar driving state from being generated. The method includes varying a throttle valve from its fully closed position to its fully opened position while maintaining a constant engine rotation number, carrying out operation for storing an output torque N at that time using at least three kinds of different engine rotation numbers, determining each obtained torque curves A˜E as actual machine data, and preparing a map based on the actual machine date. The map is prepared by describing each of the torque curves A˜E on the same X-Y plane based on the actual machine data, converting actual machine data function for describing torque approximation curves a˜e with respect to throttle opening degrees (X axis) on the same X-Y plane while making approximations to the torque curves determining the existence of intersecting torque approximation curves a˜e and automatically correcting one of the torque approximation curves c which can be determined peculiar such that a value Y of y-component of the torque approximation curve c which appears peculiar among the intersecting torque approximation curves b and c in the determining step assumes a median value Y , Y of values of y-components of the vertically adjacent torque approximation curves b and d.