What is an "Integrated ECU"?
Description of the core technology that enables highly advanced functions in vehicles
ECUs control devices and systems installed in vehicles. In recent years, the rapidly evolving automation and electrification of automobiles have made functions more complex, leading to the demand for more advanced systems. This article explains what an ECU is, the role of ECUs in vehicle functions according to their purpose and application, and the "integrated ECU", which is expected to hold the key to enabling highly advanced functions in ADAS (Advanced Driver Assistance Systems) and connected cars.
Basic knowledge about ECUs (Electronic Control Units)
ECU is an abbreviation for "Electronic Control Unit", which means a device (unit) that controls a system with electronic circuits.
A conventional ECU referred to the "Engine Control Unit", an in-vehicle microcomputer that electronically controls the engine. However, in recent years, the Society of Automotive Engineers (SAE) and the International Organization for Standardization (ISO) have defined the computer that controls the equipment and systems installed in automobiles as ECU. The engine control unit is called ECM (Engine Control Module) in SAE and ISO.
Role of ECUs
The role of the ECU is to control all devices and systems installed in a vehicle, such as automobile engines, brakes, power steering, airbags, power windows, car air conditioning, car navigation systems, key locks, sliding doors, wipers, etc.
For example, in the case of a power window, it controls the motor to open or close the window when a button is pressed, and to calculate and quantify the load to determine whether to stop or return if something gets caught in the window during operation.
In the case of an airbag, the sensor sends values about the degree of impact, to activate the airbag and determine how to control the seat belt.
This is made possible by software embedded in the ECU, and each ECU is linked via an in-vehicle network.
Increasingly complex automotive functions
Information from sensors outside the vehicle (cameras, high-frequency radar, etc.) is sent to ECUs involved in ADAS (Advanced Driver Assistance Systems), processed by algorithms, and connected to driving assistance for the driver.
Driver assistance functions include ACC (Adaptive Cruise Control), LKS (Lane Keeping Support), LCA (Lane Change Assist), AEB (Automatic Emergency Braking), and TJA (Traffic Jam Assist), which require more complex and faster processing to recognize targets and make situational judgments tailored to each purpose. As the functions required for automobiles have become more complex in recent years, the systems have also become more and more complex.
"Integrated ECUs" are expected to be the key in increasingly complex in-vehicle systems
Today's automobiles may have more than 100 ECUs. In recent years, there have been growing expectations for "integrated ECUs" that integrate these technologies. Integrated ECUs that control the entire vehicle enable complex functions as well as reduced component count and total weight.
Integrated ECUs are also expected to play an important role in Advanced Driver Assistance Systems (ADAS), which are expected to increase further in the future as a technology that assists drivers in safe and comfortable driving.
Software engineers play a key role in achieving highly advanced functions in vehicles
Software is key in integrated ECUs. Compared to 10 million lines of software in a single vehicle 10 years ago, automated-driving vehicles contain 300-500 million lines of code. To put that in perspective, it would take approximately 18,000 pages to print even one million lines of software code.
In addition, the development style is changing as more software is added to the development process. In the past, waterfall development was common, but now agile development (in which the system's requirements definition, design, development, testing, and release are repeated in small increments) and DevOps are being adopted.
*Agile development: A development method in which "planning → design → development → testing → release" are repeated in short cycles.
*DevOps: A flexible and speedy development method in which developers and operations staff work together
It can be said that the role of software engineers has become increasingly important in order to achieve highly advanced functions in automobiles and protect the safety and comfort of drivers.
*Information contained in this article is current at the time of data collection. (Published on November 17, 2022)