Electromechanical electronic control units and actuators

### Electromechanical electronic control unit and actuator

In the field of modern engineering technology, the level of intelligence and automation of electromechanical systems is increasing day by day. Among them, electronic control units (ECU) and actuators, as core components, play an indispensable role. They work together to realize the whole process automation control from signal acquisition, processing to action execution, and are widely used in many fields such as automobiles, industrial automation, aerospace and smart homes. This paper aims to deeply explore the basic principles, interactions and importance of electronic control units and actuators in electromechanical systems in practical applications.

#### 1. Overview of electronic control unit (ECU)

As the "brain" of electromechanical systems, electronic control units are intelligent control devices that integrate microprocessors, memory, input and output interfaces and special circuits. It can receive various signals from external devices such as sensors, and after internal algorithm processing, it sends control instructions to actuators, thereby realizing precise control of electromechanical systems. The design of ECU is highly integrated and modular, which not only improves the reliability of the system, but also facilitates maintenance and upgrades.

**1.1 Core functions**

- **Data processing**: Filter, amplify, A/D convert and process the input signal of the sensor to extract effective information.

- **Logical judgment**: Based on the preset program algorithm, perform logical judgment on the processed data to determine the next operation.

- **Control instruction output**: According to the judgment result, send a control signal to the actuator to adjust the system state.

**1.2 Key technologies**

- **Embedded system**: ECUs are mostly designed with embedded systems, which have efficient real-time processing capabilities and low power consumption characteristics.

- **Communication protocol**: Bus protocols such as CAN and LIN ensure effective communication between ECU and other controllers or sensors.

- **Software programming**: Use high-level languages ​​such as C/C++ for programming to implement complex control logic.

#### 2. Functions and classification of actuators

Actuators are devices in electromechanical systems that convert electrical energy, hydraulic energy, air pressure energy, etc. into mechanical energy, and directly drive the load to complete the predetermined action. It is the final executor of ECU control instructions, and its performance directly affects the control accuracy and response speed of the entire system.

**2.1 Main functions**

- **Energy conversion**: Convert different forms of energy into mechanical energy to drive the load to move.

- **Position control**: Accurately control the position, speed, acceleration and other motion parameters of the load.

- **Force/torque output**: Output the corresponding force or torque according to the control instruction to meet the working requirements.

**2.2 Common types**

- **Motor actuator**: Such as DC motor, stepper motor, servo motor, etc., widely used in automated production lines, robots and automotive power systems.

- **Hydraulic/pneumatic actuator**: Use the pressure energy of liquid or gas to achieve high torque and high thrust motion control, which is common in heavy machinery, engineering machinery and other fields.

- **Electromagnetic actuator**: Such as solenoid valve, electromagnet, etc., driven by electromagnetic force to achieve fast and precise switch control.

#### 3. Collaborative work of ECU and actuator

In electromechanical systems, the collaborative work of ECU and actuator is the key to achieving efficient and precise control. ECU collects system status information in real time, processes and makes decisions quickly, and sends control instructions to the actuator; the actuator responds quickly and drives the load to change according to the predetermined trajectory or state. This closed-loop control process not only improves the automation level of the system, but also enhances the stability and adaptability of the system.

**3.1 Closed-loop control system**

The closed-loop control system introduces a feedback mechanism to feed back the actual output state of the actuator to the ECU, compare it with the expected state, and form a deviation signal. The ECU adjusts the control strategy according to the deviation signal and continuously corrects the output of the actuator until it reaches or approaches the expected state. This control method effectively reduces the impact of external interference on system performance.

**3.2 Fault diagnosis and protection**

ECU also has fault diagnosis and protection functions. When the system is abnormal, the ECU can quickly identify the source of the fault and send a fault code to the ECU.