Double Axle Roller - Projects Automotive Industry

Power Train, Research & Development · Vehicle test rigs

Double axle roller test rig for acoustic tests

A double axle roller test rig at the FORD development center
in Cologne-Merkenich

A double axle roller test rig was installed at the FORD development center in Cologne-Merkenich for determining vehicle interior noise and vibration measurements on the vehicle structure. The test rig is used to test small private vehicles through to light commercial vehicles. Particular attention was paid to the low-noise design of the test rig components because of the acoustic requirements.

Test rig design

The test rig basically comprises two sets of rollers with a fixed front and a movable rear axle. The rollers are designed as double rollers (diameter 500 mm) with Cr-steel flame-proof coated surface (0.5 mm thick).

The axle base is adjustable by lifting spindles. The lifting ramps for easier vehicle drive-off are also used as a lift for maintenance work. The two sets of rollers are driven by a common DC generator via a belt drive and switchable clutches. A torque computer is used for measuring the tractive force which also takes into account the different losses in single axle and double axle operation. A holding and guiding system prevents the vehicle from veering off to the side.

Technical Data

Maximum braking performance (continuous operation)	326 kW
Rated tractive force	12600 N
Maximum speed	200 km/h
Roller diameter	500 mm
Adjustable gauge range	2100 - 3200 mm
Maximum axle load	2600 kg
Simulation range of the vehicle mass	600 - 2100 kg

Control types

Speed control
Tractive force control
Drive simulation (road resistance including gradient, vehicle mass)
Calibration
Coast down
Accelerator position control

Operation

The test rig has a setup mode (lifting ramps, wheel base setting, accelerator adaptation) and can be used in either manual or automatic mode. In the case of manual mode, selection and setpoints are preset on an operator panel (with graphic display). In automatic mode, a PC is used with a WINDOWS user interface that also supports mouse-free operation.

The plug and play card PC with CATSNT is integrated in a common SIMATIC frame with the digital control and the process I/O. Information is exchanged via an internal bus system by short, interference-free routes in the internal format.

Division of the user interface

operation of the test data
test preparations
test execution
system setting
password protection

The setpoints can be set optionally:

via PC keyboard or mouse
from the drive profile stored on the PC
externally via sockets by a master system

As well as in the online mask, all analog variables can be parameterized in an additional measured value display (display with limit value monitoring).

In the control type "Drive simulation" a driver terminal can be used to preset the drive profile so that it displays a speed curve on a monitor for the driver in the vehicle to follow. Drive profile processing can be started, stopped, continued or ended with a manual control unit in the vehicle. The mask below shows the whole drive profile at the left of the screen. To the right of it the current drive profile window is shown enlarged.