Maturo DYN 4WD_I Dynamometer Into Turntable

The Dynamometer DYN 4WD is constructed as a chassis dynamometer, which can be integrated into a turntable. Two active elements are used for vehicles with rear/front or four- wheel drive. The four roller pairs are independently operational. Each vehicle wheel is driven by a separate motor/generator system. It can be used for acceleration/retardation and in an endurance mode.

EMI/EMC
The Dynamometer DYN 4WD is prepared to be used in an anechoic chamber for EMI and EMC measurements. All electronic components are located in a separate box, which is shielded, and radio interference suppressed. The RF- Emission is more than 15 dB under limit “B” on CISPR 12 and CISPR 25. The immunity against continuous field strength up to 200 V/m is guaranteed.

Control Unit
Each active element has two micro controller to control the frequency inverters and for the speed measurement system. The element is connected to the system controller via fibre optic links. The system controller PC is equipped with an IEEE or LAN interface for remote control with a measurement software.

Safety and Emergency Function
The maximum speed is limited by inverter function controller and by the internal micro controller. The temperature on the motors and inside the electronic box is being watched. Two emergency switches are located close to the stand and in the control room. In case of an emergency, the motor power will be switched off and the motors come to a standstill.

Signal Lamp

The signal lamp in control room shows the state of the dynamometer: Green continuous -> Emergency is ok Green flashing -> Emergency pressed Orange continuous -> Dc voltage link off Red continuous -> Dc voltage link on Red flashing -> Dynamometer is started

Rollers
The rollers are static heaved up to 2000 rpm and flame-coated.
The surface of the rollers is comparable with road surface.
Balance quality: Q 2.5 according to VDI 2060

Fig.: Double roller system

ABS and ESP tests
The dynamometer DYN 4WD allows ABS and ESP testing of vehicles up to an acceleration or deceleration of 1.0 g (10 m/s²).

Structure:
The 4 independent roller pairs of the dynamometer are integrated into a “self-contained” frame, which minimizes the dynamic energy output to the turntable. The frame itself is placed into the turntable as pre-assembled assembly group for an easy installation of the system.

Wheel Base
Independent adjustment of the front and rear axle allows to adjust the position of the vehicle in respect to the centre of the turntable. Adjusting speed: approx. 20 mm/s Positioning accuracy: +/- 2 mm Operation of the wheel base adjustment is only possible at a standstill of the dynamometer.

Shutter system in track area
An overlapping “roller-type shutter” connection between the axles avoid gaps at the surface in every position of the wheelbase. Each element is connected with conductive material to the turntable surface and the next element. The max. permissible axle load in the track area is 2000 kg.

Fig.: Shutter System F

Fixing Elements
The system is equipped with four lashing straps to fixing of the vehicle while running. Spring hooks allow an easy connection to the four fastening bolts. The fixing elements are integrated into the structure of the system and are adjustable to the specific vehicle sizes. The straps are made of electrically neutral material. Length adjustment: from 1.0 to 6.0 m Tensile strength: 5000 N

Fig.: Fixing system

Single-wheel drive for motorcycles testing
The Dynamometer DYN 4WD is equipped with a function for testing motorcycles or any other motorised two-wheeler. The system and the software allow the selection of the operation of only one single roller.

Fig.: Testing of motorcycles

Cooling fan system
Shielded fans provide a sufficient cooling for the tyres and the motor of the vehicle under test.
A removable plastic air scoop on top of the turntable is used to detour the airflow.
The fan speed can be set either stepwise to the roller speed (up to 60 km/h) or to a constant speed by the dyno software.
Installation of the cooling fans is below the cover
Wind speed: 60 km/h
Air flow: 10.000 m³/h

Fig.: Cooling fan system

Software and functions of the Dynamometer

The included software contains the following functions:
- Emergency stop
- Start cycle / stop cycle
- Speed control of the rollers
- Speed control of the ventilator
- Force at the rim (in Nm)
- Distance gone from the start of the cycle (in km)
- Cycle recording (profile)

To allow the following test cycles:
- Constant velocity
- Velocity gradient
- Street (road) simulation
- Simulation of uphill and downhill driving
- ABS, ESP testing with acceleration/deceleration of up to 1.0g
- Single-wheel drive fort wo-wheelers

The software includes:
- PC-Controller with keyboard, mouse and monitor
- The DYN-Software is pre-installed at the PC

Software Description (Example)

 Operation modes:  

The following modes are available:
- Constant Velocity - "ConVelo" driving with constant speed
- Gradient Mode - "GarVelo" performing a driving profile; e.g. for ABS testing
- Road Simulation - "RoadSim" for road simulation with counter torque
- Measurements
- Block Rolls - “Block Rolls” to drive in and out with car

Constant Velocity: 

At the operating mode “ConVelo” it is possible to set a certain speed, acceleration and deceleration. These values are limited by the limits of the dynamometer or the limits of the used vehicle.

This mode can be activated with the “Start” key and stopped with the “Stop” key.
The current values of speed and torque are displayed for each motor.
The speed curve is displayed as a graph.