Hardware In the Loop Test
Powertrain testing is undergoing radical change, driven by the challenges
that global society face today. The need for reduced dependence on fossilfuels
and improved carbon-footprints are driving changes in the technologies
used in all vehicles. This in turn has a direct impact on approaches to
testing of Powertrain components and systems.
We have extensive experience and capability in the technologies that are
required to test the new generation of powertrains that are emerging around
the globe, ensuring we are able to provide the very best solutions for your
Powertrain and transmission testing requirements.
Hardware-in-the-loop cells test components and sub-systems of the
powertrain and often include simulation of other components that are
absent from the test.
Froude Hofmann has developed a range of Powertrain test systems that
provide the right solution for the above testing requirements, evolved from
many cutting edge technologies it deploys in its other product lines.
Conventional embedded component testing, although ideal, is not a practical approach in today's fast moving development programmes. Hareware-in-the-Loop test systems are therefore required to test selected Powertrain units at an early stage of development, whilst simulating the presence of other elements and subsystems. This provides a more time and cot efficient development process, allowing individual components to be tested and critical decisions to be made, without delay.
Today’s demands have introduced new technologies which require additional testing.
This includes the need for the cell to test hybrid motors, battery simulators, bespoke
inverters and expanded instrumentation.
High levels of flexibility are required from today’s Hardware-in-the-Loop test cells to
accommodate the wide range of technologies that are being developed. This requires
individual testing of the prime movers, a fully synchronised test with power sources
operational and simulation of multiple configurations.
Component test systems demand ‘Real World’ simulation techniques to be applied to
established control strategies developed on the actual hardware. These assemblies are
then subjected to ‘life cycles’ that will be experienced in the full vehicle.
Often innovative transmission and powertrain systems are used in hybrid engine
configurations, such as epicyclic gearings and continuously variable transmissions.
The full front-wheel drive powertrain test bed consists of an IC engine/electric motor
connected to inline differential. This feeds the final drive half-shafts which are each
coupled to an AC dynamometer. The powertrain assembly is supported by an adjustable
pallet system which allows quick change-over of different powertrain systems.
Embedded components, such as the prime-mover in the vehicles’ Powertrain (typically
an electric motor and conventional internal combustion engine in a parallel hybrid system)
can be tested individually on their respective AC dynamometers, or the two systems can
be synchronised to provide full simulated road load conditions.
This provides a unique test environment where the components can be physically present
or alternatively simulated using sophisticated software modelling to establish a fully flexible
HIL test facility. This is fully integrated using our ‘genysis’ control system.
Simulations that may be incorporated in test-cell solutions include:
- Component simulation
- Hybrid Strategy evaluation
- Energy storage simulation
- Battery cycling
- State of Charge evaluation
- Vehicle dynamics
- Driver ‘styles’, real-world route and traffic simulation
Our innovative ‘dual test bed’ concept provides great flexibility for testing prime movers whilst
the control system provides the sophisticated simulation for numerous Powertrain configurations.
The dual test facility provides simultaneous control over different prime movers within a
hybrid system.
Vehicle Motor Inverters:
Typically a manufacturer will need to test a range of hybrid and electric-vehicle powertrains.
Predominantely, this requires a range of electric motors to be tested within the same testcell.
We have developed sophisticated control software integrated with the world’s leading
invertor technology to perform these demanding applications.
Battery Simulators:
Battery simulators can be provided in configurations to suit the range of vehicles to be
tested in the cell.
Robot Driver:
Our ‘Robot Driver’ system, capable of rapid set-up, self-learns the range of manual and automatic
gearboxes it will be presented with. It provides a test cell with repeatable cycles, class-leading
response times, and real-world simulated conditions when used in conjunction with the vDriver
product. We have been designing robots for over 25 years and they are seamlessly integrated
with our cell control-systems.
Ancillary Equipment:
We have designed modular supporting ancillary equipment, to suit a wide range of engines,
drive-couplings and transmissions. These include:
- Drive shaft systems
- Isolated base plates for test bed components
- Engine mounting systems
- Pallet systems
- Universal Engine & Transmission mounting options
- Oil and water conditioning systems
- Fuel conditioning and flow measurement
- Full data aquisition and data analysis packages
vDriver:
‘Real World’ is becoming an essential part of Powertrain testing, to ensure that the product
will perform as expected in demanding conditions globally. This is particularly important
where the complex strategies of the latest powertrain systems have to accommodate varying
and interactive circumstances and still perform and control effectively. Our vDriver platform
can simulate the variability associated with particular driving styles and routes taken from
around the world. This solution reproduces them repeatably in the test-cell, and includes full
traffic and road-hazard simulation.
