Racing technologies: Electronic Control Unit

    Hello colleagues! image
    Today, I will deviate a little from the traditional topics of information security for me and talk about the electronics with which I work in my spare time: engine control systems for racing cars.
    But let's start with a description of the situation as a whole. In motorsport, as well as in many other technical sports, quite often the result depends not only on the athlete, but also on the “projectile” that he uses. Therefore, a professional approach to the preparation and tuning of the car is required. Of course, there are a lot of nuances. But if roughly divided into parts, it will be tuning the chassis and tuning the engine. Today I would like to tell you what kind of electronics are used when working with the "heart" of racing cars.

    A modern racing engine (like the engines in your cars) is controlled by a specific computer: Electronic Control Unit. He is responsible for all the processes taking place with him and manages all the on-board electronics. The most popular solutions are made by companies such as Motec and Pectel . I use the Motec M800 in my car , on the example of which I will tell you how it works.

    imageIn fact, the ECU is a computer that contains engine control algorithms, tools for collecting information and the ability to control external devices. In terms of operation algorithms, a 4-stroke gasoline enginea very simple device, and not so much is required to manage it. We will need knowledge about the position of the crankshaft (speed and reference mark sensor), the position of the throttle valve and / or throttle position sensor. We also need to know the amount of air entering the engine. To do this, use MAF (Air Flow) or MAP (Air Pressure) sensors. As control elements, we will use injectors for fuel supply and ignition coils. In general, the list I have listed is already enough to start the engine. The data collected allows the ECU to understand when it is necessary to supply fuel and ignite it. But the question remains, how much fuel to supply and when exactly to make the ignition? But this data already represents what is called “firmware” in jargon.

    For external control, Motec computers use a CAN bus. To connect the laptop to it, special CAN-to-USB adapters are used . As an editing program, ECU Manager is used , available for download and “training” for free on the manufacturer’s website. If you want to see what the management of a running engine looks like, then run WinEMP.exe with the “demo” parameter.



    This software allows you to make adjustments to almost all aspects of the motor. One of the main parameter control algorithms is PID control.. With its help, all dynamic processes are described. The rest is implemented by the functions described by the tables. The main feature is the ability to create a tabular dependency between any available elements. Thus, the programmer is practically unlimited in the possibilities of setting behavior algorithms. Using input parameters and controlling external devices, you can describe the behavior of the engine in almost any environment.

    But to monitor the operation of all engine components on the fly is quite difficult. Therefore, an accompanying process is the collection and analysis of the ECU system log. Logging settings are quite rich and allow you to control all the necessary parameters. The i2 Manager program is used for this.from the same manufacturer. With its help, already in a "calm" environment, the readings of the sensors are analyzed. This invaluable information allows you to fine-tune all the parameters.

    To communicate with the outside world, the ECU has a set of incoming ports and "control" outputs. As input, it can both receive digital signals via CAN, and analog information in the range 0-12V through built-in programmable ADCs. A rich palette of settings allows using the GUI to configure the ECU for almost any external sensor. Output ports mean “logical” control of external devices. But their choice is not so wide and pre-allocated to the “injectors”, “ignition” and “periphery” depending on the output characteristics. But in the end, this set of features allows you to connect the ECU to any car.

    In general, it is precisely this process of calibrating and tuning the engine that is the trade secret of tuning studios and racing teams. Around him, an areola of "mystery" and "complexity" is deliberately created. But do not assume that this process is so problematic: any more or less literate programmer will cope with it, having figured out how the engine works. Just do not rush into the quarry and change the ignition angles, not understanding what it is.

    Hope I told you something new. Thanks for attention.
    If this topic is interesting, I can describe in more detail the process of tuning the engine in a new article.

    Also popular now: