Control systems in future off-highway and commercial vehicles
Today we all see an increased amount of regulation and rising energy prices influencing our daily business, especially considering end users of off-highway and commercial vehicles. Electrification is widely seen as a solution to improve TCO (Total Cost of Ownership) but it is not an easy task to develop next generation machines with improved energy efficiency at a reasonable cost level.
The most expensive components and sub-systems in future electrified and highly automated vehicle powertrains are typically the battery, inverters and electric motors and thermal management systems. There are also various other components and systems in the vehicles, for example, hydraulics, on-board chargers, DC/DC converters, lights and working lights, telematics, assistance systems, traction control, ABS, HVAC, locks, etc. All of these components and systems shall work together in a way that the vehicle is safe and has the best possible performance and user value.
Complexity increases a lot when an OEM starts to look at the cost optimization of an electrified vehicle. In many cases optimization leads to a situation where there are several different suppliers for all components in a vehicle. It is not an easy task to integrate components together while simultaneously considering functional safety, performance and user experience. The software of a vehicle should also be developed in a way that allows for continuous development and maintenance.
The importance of vehicle drive cycle should also be pointed out. To be able to successfully develop next generation electrified and highly automated vehicles, understanding the drive cycle needs to be at the centre of the development. Utilizing simulations and model-based design, the selection of vehicle topology and component dimensioning is possible. Simulations are also important for software development. Without understanding how the vehicle is used and without knowing vehicle work tools and drive train efficiencies, optimization of the fuel economy is not possible to optimize energy consumption and productivity. These are both important factors of the TCO.
Control systems in vehicles are also developing. We are moving from single vehicle control units towards zonal architectures with built-in functional safety and non-safety vehicle software. The best option is to use the same software in different vehicle models from the same platform. Control system hardware has to be really durable, functional safety compliant and also include all the necessary features.
Main steps in simulation driven development of systems and software:
- System modelling based on measurement data, laws of physics and other knowledge, including system component physics, which play a major role in the system
- Defining realistic functional requirements based on the system analysis and simulations
- Designing optimal control and supervisory algorithms based on the requirements system models and simulations
- Generating code for ECU deployment and a real-time test bench for system verification without physical prototype
- Control system hardware in the loop simulations for system level testing and integration
- à Gaining strategic advantage by reducing time to market, increasing system and software quality, reducing product development risk, minimizing rework during system life cycle
Epec is a Finnish technology company and a system supplier of electronics and software for off-highway and commercial vehicle industry. “We have a long history delivering control systems for various OEM’s. We believe in the future the software and electronics and systems engineering are the core know-how all OEM’s need. Off-highway and commercial vehicles are already software products”.
Jyri Kylä-Kaila, CEO, Epec Oy