Developing a deterministic, easy-to-use, automatable, and easily maintained platform for open- and closed-loop testing on multiple linked electronic control modules (ECMs) and electronic control units (ECUs), that can also be configured to support a number of different product lines.
Creating a generic hardware platform for the customer to perform ECM/ECU integration testing and a software solution that allows a highly configurable setup and automated configuration to suit multiple product lines and variants.
David Catto - Austin Consultants
Chris Thoroughgood - Austin Consultants
Austin Consultants is a team of highly certified engineers that have created software, electronic, and mechanical solutions for a variety of industries, including automotive and aerospace, for over a decade. We deliver full turnkey solutions or can work with our clients to take on any section of a project by sharing the experience and expertise of our qualified and passionate team. We build long-term relationships with our clients and provide full maintenance, training, and ongoing support for projects. We are also the highest certified NI Alliance Partner in the United Kingdom with specialist expertise in VeriStand software.
The Caterpillar Advanced Components and Systems Division handle full system integration testing for many of Caterpillar’s popular product lines. This system integration activity involves linking up multiple ECUs and ECMs, alongside real displays, technician tools, and other connected systems that form part of the internal infrastructure of a vehicle.
As the vehicles themselves get more and more complex, the full system tests become more time consuming and a manual approach becomes less viable due to reliance on human resources and differences in how these tests are performed (timing and interpretation). The previous testing process was very manual as many of the tests involved setting an indicator and looking for a result either on a separate CAN tool or perhaps on a display.
Austin Consultants took a Windows-based system with custom conditioning electronics (developed by Caterpillar) and migrated it to a custom full-featured, hardware-in-the-loop (HIL) platform. The platform runs a real-time OS and real-time testing engine. It features simulated instrumentation, custom FPGA signals, deterministic I/O, and is driven by a highly configurable system setup and user-definable interface.
We worked alongside the Caterpillar team to create a real-time hardware platform based on a PXI real-time controller. In addition, Caterpillar designed conditioning electronics (to bring signal levels to a suitable format) to directly interface with the ECUs/ECMs and a custom-built hardware platform.
Our hardware design involved a review of the existing Caterpillar hardware and understanding the day-to-day challenges that the operators faced, such as maintenance and servicing. The result was a double 24u floor standing rack. On one side was all the NI hardware and the signal conditioning PCBs/modules developed by the customer, including all power supplies and safety circuits. We focused on making these aspects easily maintainable with the following features:
We dedicated the second rack to FIUs. In this rack, we supplied and fitted an FIU controller and the rest of the rack allowed for the customer to fit in product-specific FIUs and load trays. This makes the system very versatile and means that one asset can be used to test a wide range of products.
From a hardware point of view, this project was largely a refresh and repackage of existing Caterpillar systems. We added value with the software aspects of the rig. By fitting a PXI real-time controller and using our extensive knowledge of VeriStand, we could offer a real-time test (HIL) engine to give the customer a very flexible solution. We provided the hardware and software expertise to integrate this into a solution for the customer.
By exploiting the power of VeriStand and embedded real-time hardware, we delivered a system with many benefits. The system has deterministic communications and simulated behaviour. It also has the flexibility of using deterministic targetable FPGAs for customisable measurements synchronised with the primary control-loop rate. This gives the customer great flexibility and the capability to meet more complex design requirements in the future, such as missing tooth cam/crank signals.
We took advantage of the VeriStand framework to concentrate on customer-specific components, such as the integration of hardware and other interfaces not supported off the shelf, as well as custom devices to talk to the ECM/ECUs via CAN bus.
The benefits of using VeriStand and some of the reasons behind its utilisation in this project include:
We have also provided custom functionality to translate Excel-based configuration files to specific system configurations, allowing easy selection of multiple types of products, which then configures the system to test on the same hardware platform. This configuration-based approach helps the customer to easily extend the capability of the equipment on their own.
Caterpillar can run automated testing in a much more controlled manner and with much less operator input because of the built-in stimulus profile and real-time sequence editors, along with custom additions and training.
The hardware platform worked with Caterpillar to realise (on top of NI equipment): FIU/FIU with load/frequency generation/PWM generation (optical isolation) CAN. Use different harnesses rather than complete matrix channel switching.
We have a vast knowledge of HIL test applications. Caterpillar extensively uses HIL testing throughout its business. The company approached us to help migrate an existing HIL test bench into a standardised platform that can be expanded to support current and future ECU products.
Caterpillar’s Advanced Technologies and Solutions team are responsible for the electronic systems on a wide range of the Caterpillar products. Integration verification involves testing the entire electronic control system for a particular product as a system. We designed this bench specifically for the material handler product, but we want the hardware to be generic enough to be replicated and used for other product lines with simple reconfiguration.