Vehicle testing device and vehicle speed deviation calculation method for vehicle testing device

Patent metadata

Field	Value
Publication number	US-10379004-B2
Application number	US-201615771482-A
Country	US
Kind code	B2
Filing date	Aug 10, 2016
Priority date	Oct 30, 2015
Publication date	Aug 13, 2019
Grant date	Aug 13, 2019

Abstract

To obtain vehicle speed deviation data for changeover between accelerator and brake properly with inclination of a standard mode. In technique of calculating a changeover vehicle speed deviation from accelerator to brake in driving vehicle along standard mode (target vehicle speed) of vehicle drive pattern defined by time and vehicle speed within range of predetermined vehicle speed and time deviations from standard mode, an inclination AB of the standard mode is calculated by approximate differentiation of vehicle speed at a judgment standard point A of a current time instant on standard mode, first inclination AB is multiplied by an accelerator-to-brake changeover time deviation preset value Δt −1 , and the accelerator-to-brake changeover vehicle speed deviation from the judgment standard point A to a changeover judgment point E for changeover at the current time instant is calculated by addition of the product and an accelerator-to-brake changeover vehicle speed deviation preset value ΔV −1 .

First claim

The invention claimed is:

1. A vehicle testing apparatus for performing vehicle tests by operating a vehicle on a chassis dynamometer, the vehicle testing apparatus comprising:
the chassis dynamometer; and
a controller configured to:
control a speed of the vehicle on the chassis dynamometer by performing changeovers between an accelerator operation to accelerate the vehicle and a brake operation to decelerate the vehicle;
calculate at least one of a first changeover vehicle speed deviation for changeover from the accelerator operation to the brake operation or a second changeover vehicle speed deviation for changeover from the brake operation to the accelerator operation in a vehicle speed following control to drive the vehicle along a standard mode of a vehicle drive pattern defined by time and a vehicle speed within a range of a deviation of a predetermined speed and a deviation of a predetermined time from the standard mode;

wherein the controller is further configured to perform at least one of
a first calculating process of calculating a first inclination of the standard mode by approximate differentiation of the vehicle speed at a judgment standard point of a current time instant on the standard mode of the vehicle drive pattern, multiplying the first inclination of the standard mode by a first changeover time deviation preset value which is a preset value of a time deviation for changeover from the accelerator operation to the brake operation, and calculating the first changeover vehicle speed deviation from the judgment standard point to an accelerator-to-brake changeover judgment point for changeover from the accelerator operation to the brake operation at the current time instant by addition of a product determined by multiplication of the first inclination and the first changeover time deviation preset value and a first changeover vehicle speed deviation preset value which is a preset value of the vehicle speed deviation for the changeover from the accelerator operation to the brake operation; or
a second calculating process of calculating a second inclination of the standard mode by approximate differentiation of the vehicle speed at a judgment standard point of the current time instant on the standard mode of the vehicle drive pattern, multiplying the second inclination of the standard mode by a second changeover time deviation preset value which is a preset value of the time deviation for changeover from the brake operation to the accelerator operation, and calculating the second changeover vehicle speed deviation from the judgment standard point to a brake-to-accelerator changeover judgment point for changeover from the brake operation to the accelerator operation at the current time instant by addition of a product determined by multiplication of the second inclination and the second changeover time deviation preset value and a second changeover vehicle speed deviation preset value which is a preset value of the vehicle speed deviation for the changeover from the brake operation to the accelerator operation.

2. The vehicle testing apparatus as claimed in claim 1 , wherein
an upper limit allowance line is defined as a line connecting upper limit points each of which is an upper limit point at a given time instant deviated from the standard point of the standard mode at the given time instant by the predetermined speed and the predetermined time,
a lower limit allowance line is defined as a line connecting lower limit points each of which is a lower limit point at a given time instant deviated from the standard point of the standard mode at the given time instant by the predetermined speed and the predetermined time,
an accelerator-to-brake changeover line is defined as a line connecting the accelerator-to-brake changeover judgment points each of which is the changeover judgment point for changeover from the accelerator operation to the brake operation at a given time instant in a standard mode running operation,
a brake-to-accelerator changeover line is defined as a line connecting the brake-to-accelerator judgment points each of which is the changeover judgment point for changeover from the brake operation to the accelerator operation at a given time instant in the standard mode running operation, and
at least one of the first or second changeover time deviation preset value and the first or second changeover vehicle speed deviation preset value is set at a third preset value within a range demarcated by the upper limit allowance line or the lower limit allowance line.

3. The vehicle testing apparatus as claimed in claim 1 , wherein the controller is configured to perform a changeover from the accelerator operation to the brake operation when a vehicle speed sensed at a time instant of a judgment standard point becomes higher than a first changeover line and to perform a changeover from the brake operation to the accelerator operation when the vehicle speed sensed at a time instant of a judgment standard point becomes lower than a second changeover line, the first changeover line being defined as an accelerator to brake changeover line connecting a plurality of accelerator to brake changeover judgment points of a sequence of time instants in a running operation of the standard mode, and the second changeover line being defined as a brake to accelerator changeover line connecting a plurality of brake to accelerator changeover judgment points of a sequence of time instants in a running operation of the standard mode.

4. A vehicle testing method for performing vehicle tests by operating a vehicle on a chassis dynamometer, the vehicle speed testing method comprising:
controlling a speed of the vehicle on the chassis dynamometer by performing changeovers between an accelerator operation to accelerate the vehicle and a brake operation to decelerate the vehicle; and
calculating at least one of a first changeover vehicle speed deviation for changeover from the accelerator operation to the brake operation and a second changeover vehicle speed deviation for changeover from the brake operation to the accelerator operation in a vehicle speed following control to drive the vehicle along a standard mode of a vehicle drive pattern defined by time and a vehicle speed within a range of a deviation of a predetermined speed and a deviation of a predetermined time from the standard mode, in a vehicle testing apparatus for performing vehicle tests by operating a vehicle on the chassis dynamometer, wherein
the first changeover vehicle speed deviation is calculated by calculating a first inclination of the standard mode by approximate differentiation of the vehicle speed at a judgment standard point of a current time instant on the standard mode of the vehicle drive pattern, multiplying the first inclination of the standard mode by a first changeover time deviation preset value which is a preset value of a time deviation for changeover from the accelerator operation to the brake operation, and calculating the first changeover vehicle speed deviation from the judgment standard point to an accelerator-to-brake changeover judgment point for changeover from the accelerator operation to the brake operation at the current time instant by addition of a product determined by multiplication of the first inclination and the first changeover time deviation preset value and a first changeover vehicle speed deviation preset value which is a preset value of the vehicle speed deviation for the changeover from the accelerator operation to the brake operation, and
the second changeover vehicle speed deviation is calculated by calculating a second inclination of the standard mode by approximate differentiation of the vehicle speed at a judgment standard point of the current time instant on the standard mode of the vehicle drive pattern, multiplying the second incl

Assignees

• Meidensha Electric Mfg Co Ltd

Inventors

• Kanke Masayasu

Classifications

• G01M17/007

  Wheeled or endless-tracked vehicles (G01M17/08 takes precedence) · CPC title

• G01L5/284

  Measuring braking-time or braking distance · CPC title

• G01L5/282

  the vehicle wheels cooperating with rotatable rolls · CPC title

• G01M17/0074 Primary

  Details, e.g. roller construction, vehicle restraining devices · CPC title