An obsolete test bench often requires a renewal that takes it to the highest level of modernity with the least possible investment, optimizing resources without unnecessary waste.
Through the "AdaMo" system based on the highly scalable Real-Time / FPGA NI CompactRIO platform, it is possible to meet the specific requirements of each renewal, considering the previous settings and performances and integrating the necessary evolutions.
There are many types of test benches and in general each component or system can be tested. Consider the engine test bench as a very complete and articulated example of a bench where to perform extremely different tests between them, keeping all the following arguments valid for other types of bench.
The test benches have been used for many years to test engines both in research and development and in production, both with static and dynamic tests, both in performance and in duration. There are therefore hundreds of test benches now obsolete and often only partially usable due to their progressive deterioration. Sooner or later everyone thinks about the need for renewal but often we stop at the apparent enormity of the operation, especially when the inevitable replacement of the whole system is envisaged, without being able to recover anything.
It is clear that if once the test bench was managed by systems at the edge of the 'sartorial' and their operation required experience and art, today it is possible to design benches completely based on commercial hardware components, ie available on the market without being a monopoly of a supplier with extraordinary advantages in terms of costs, performance and speed of supply.
With the same technologies it becomes possible to intervene surgically in the existing test benches for:
■ increase system resources
■ add features not yet available - evolve the entire bank to perform new tasks.
We analyze these three levels of intervention considering that what is described is part of the functionality of the "AdaMo" system based on the CompactRIO platform. PC software supervises a CompactRIO network where, combining Real-Time and FPGA programming with a powerful scalability and configurability of hardware architectures, there is distributed, deterministic and reliable management of measurements, control and automation, managing to concentrate the resources in the features of the desk based on the needs and activity in progress.
This is the first level of intervention in a still functioning bank to add measurement channels as well as control nodes. Typically in this case a new primary graphical environment is not indispensable while the solution consists in identifying which interface lines are available on the desk and through these to let the new measures enter its software as well as to link the new controls. In practice, if you can use serial communications (AK protocol, Modbus, Profibus, custom protocols) or network (AK protocol, Modbus TCP, Profinet, custom protocols) or via CAN (with DBC database, CANopen, etc.), installing in the bank one or more subsystems based on "AdaMo in CompactRIO" all new measures and new controls are managed by these nodes that become intelligent and active peripherals of the old system.
Alternatively, the new subsystems can be connected via analog lines, for example by exchanging signals "± 10 V" or "4-20 mA" with existing hardware as handshake of new measures and new controls distributed and not feasible with previous resources.
Adding features not yet available In a desk created to do some activities it may become necessary to integrate special features that are impossible with the available resources, for example communication with anelectronic control unit (ECU), both acquiring and modifying (compatibly with the necessary requirements) its parameters. We need specialized hardware and software components to be integrated with the existing system.
Another example is the expansion of the user interface by adding windows and graphics; or another example is the management of measuring instruments such as smoke, consumption, pollutant analysis, etc. When the existing desk can not connect due to hardware or software limits, it makes sense to think about integrating new, intelligent, active distributed subsystems, integrating, not replacing or scrapping. Evolving the entire bank to perform new tasks even when it is decided that the bank must be substantially evolved becoming capable of new activities, it is efficient to design this revolution through the AdaMo system based on the National Instruments CompactRIO platform.
All power supplies already present for eddy current brakes and mechanical actuators are used, or more modern components are used, limiting the replacement to the power part only, since all the controls (PID, predictors, etc.) are fast (revolutions, torque) , control unit parameters) that lenses (temperatures, pressures, flow rates, etc.) are managed in the CompactRIO software.
It is possible to replace a eddy current brake with an inverter-driven electric motor, in turn connected via Profinet to the CompactRIOs, as well as connecting by wire with the ECU in the accelerator control, to make the bench dynamic. We interface via ASAP 3 with INCA (or similar) to perform DOE cycles at various levels of automation.
To renew a test bench without waste, you need:
■ the highly configurable AdaMo system using internal editors (logic, graphics, mathematics, etc.)
■ the scalable and reliable CompactRIO platform
■ the experience
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