Automotive CAN bus simulation development tool Chengdu Panfeng Technology

.3 With the development of automotive decoder electronic technology, the degree of automotive electronic interference engineering continues to increase. The usual mechanical system has been unable to solve certain decoding problems related to automotive functional requirements and has been replaced by electronic control systems. Automotive electronic electronic control teaching system
The editor of Chengdu Panfeng Technology, a developer and manufacturer, has sorted out several major categories of automotive sensors for everyone, hoping to help everyone better understand and learn automotive electronic sensors. The function of the sensor is to quantitatively provide useful electrical output signals based on the specified measured size, that is, the sensor converts physical and chemical quantities such as light, time, electricity, temperature, pressure, and gas into signals. As a key component of the automobile's electronic control system, sensors directly affect the technical performance of the automobile. There are about 10 sensors installed on ordinary cars, and more on high-end luxury cars. These sensors are mainly distributed in the body control system, engine control system, and chassis control system.
1. Sensors for body control
.3 The main purpose of using this type of sensors is to improve the safety, reliability, comfort, etc. of the car. They mainly include a variety of temperature sensors used in automatic air conditioning systems, Air volume sensors, sunlight sensors, acceleration sensors in airbag systems, automatic brightness control, mid-light sensors, ultrasonic sensors, image sensors in blind spot alarm systems, etc.
2. Sensors for engine control
.3 There are many types of sensors for engine control, including temperature sensors, pressure sensors, speed and angle sensors, flow sensors, position sensors, gas concentration sensors, and knock sensors. wait. This type of sensor is the core of the entire engine. They can be used to improve engine power, reduce fuel consumption, reduce exhaust gas, reflect faults, etc. Since they work in harsh environments such as engine vibration, gasoline vapor, sludge, and muddy water, they are resistant to harsh conditions. Environmental technical indicators are higher than ordinary sensors. There are many requirements for their performance indicators, the most critical of which are measurement accuracy and reliability. Otherwise, errors caused by sensor detection will eventually lead to engine control system failure or malfunction.
.3. Temperature sensor: mainly detects engine temperature, intake gas temperature, cooling water temperature, fuel temperature, engine oil temperature, catalytic temperature, etc. The temperature sensors used in practical applications mainly include wire-wound resistors, thermistors and thermocouples. The wire-wound resistance temperature sensor has higher accuracy, but has poor response characteristics. The thermistor type sensor has high sensitivity, good response characteristics, but has poor linearity and is suitable for lower temperatures. The thermocouple type has high accuracy and a wide temperature measurement range, but needs to consider an amplifier. and cold-end handling issues.
.3. Pressure sensor: mainly detects the absolute pressure of the intake manifold, vacuum degree, atmospheric pressure, engine oil pressure, brake oil pressure, tire pressure, etc. There are currently several types of automotive pressure sensors. The most widely used ones include capacitive type, varistor type, diaphragm driven variable inductance type (), and surface elastic wave type. The capacitive sensor has the characteristics of high input energy, good dynamic response, and good environmental adaptability. The varistor type is greatly affected by temperature and requires a separate temperature compensation circuit. However, it is suitable for mass production and has a large output and is easy to output digitally. However, The type with poor vibration resistance has the characteristics of small size, light weight, low power consumption, strong reliability, high sensitivity, high resolution, digital output, etc., and is an ideal sensor.
.33. Rotation speed, angle and vehicle speed sensors: mainly used to detect crankshaft angle, engine speed, vehicle speed, etc. There are mainly generator type, magnetoresistive type, Hall effect type, optical type, vibration type, etc.
.3. Oxygen sensor: The oxygen sensor is installed in the exhaust pipe. It measures the oxygen content in the exhaust pipe and determines the deviation between the actual air-fuel ratio of the engine and the theoretical value. The control system adjusts the combustible mixture based on the feedback signal. The concentration makes the air-fuel ratio close to the theoretical value, thereby improving economy and reducing exhaust pollution. Practical applications are zirconia and titanium oxide sensors.
.3. Flow sensor: measures the intake air volume and fuel flow to control the air-fuel ratio. It mainly includes air flow sensor and fuel flow sensor. The air flow sensor detects the amount of air entering the engine to control the amount of fuel injection from the injector to obtain a more accurate air-fuel ratio. Practical applications include Karman vortex type, vane type, and hot wire type. The Karman type has no moving parts, is sensitive in response, and has high accuracy. The hot-wire type is easily affected by the pulsation of inhaled gas and is easily broken. The fuel flow sensor is used to determine fuel consumption. There are mainly water wheel type and ball circulation type.
.3. Knock sensor: It can transmit the knock signal to the control system to suppress the occurrence of knock. There are mainly magnetostrictive and non-resonant piezoelectric types.
.33. Chassis control sensors
.3 Chassis control sensors refer to sensors distributed in transmission control systems, suspension control systems, power steering systems, and anti-lock braking systems. They are used in different The functions in the system are different, but the working principle is the same as the sensor in the engine. There are mainly the following types of sensors
. Transmission control sensor: mostly used for the control of electronically controlled automatic transmissions. It is based on the information obtained from the vehicle speed sensor, acceleration sensor, engine load sensor, engine speed sensor, water temperature sensor, and oil temperature sensor. After processing, the electronic control device controls the shift point and the torque converter lock to achieve maximum power. and maximum fuel economy.
.Suspension system control sensors: mainly include vehicle speed sensor, throttle opening sensor, acceleration sensor, vehicle height sensor, steering wheel angle sensor, etc. Automatically adjust the vehicle height based on the detected information, suppress changes in vehicle posture, etc., to control vehicle comfort, handling stability and driving stability.
3. Power steering system sensor: It is based on the vehicle speed sensor, engine speed sensor, torque sensor, etc. to enable the power steering electronic control system to achieve easy steering control, improve response characteristics, reduce engine loss, increase output power, and save money. Fuel, etc.
.3. Anti-lock brake sensor: It detects the wheel speed based on the wheel angular velocity sensor. When the slip rate of each wheel is determined, it controls the brake oil pressure, improves the braking performance, and ensures the maneuverability of the vehicle. and stability.
Four vehicle sensor research and development trends
.3 Due to the important role of sensors in electronic control systems, countries around the world attach great importance to their theoretical research, new material applications, and product development. Diamond has good heat resistance and high thermal stability. Carbonization does not begin until the temperature is above ℃ in a vacuum, and carbonization does not begin until the temperature is above ℃ in the atmosphere. Using this characteristic, we can make thermal sensors suitable for high temperatures. It can monitor and control the temperature from normal temperature to ℃, and is suitable for use in harsh environments with high temperatures and corrosive gases. It has stable performance and long service life, and can be used for high-temperature measurements in engines. In addition, diamond has a high deformation rate at high temperatures. This characteristic can be used to make vibration sensors and acceleration sensors used in high temperature environments. Combined with the diaphragm of other materials, it can be used as a high-temperature, corrosion-resistant, and highly sensitive pressure sensor for vibration detection and engine cylinder pressure measurement.
Optical fiber sensors are receiving widespread attention due to their strong anti-interference, high sensitivity, light weight, small size, and suitability for remote measurement. Many mature products have been launched, such as fiber optic torque sensors, temperature, vibration, pressure, flow and other sensors.
.3 While developing and utilizing new materials, due to the development of microelectronics technology and micromachining technology, sensors are developing in the direction of miniaturization, multi-function, and intelligence. Miniaturized sensors use micromachining processing technology to integrate micron-level sensitive components, signal conditioners, and data processing devices on a chip. Due to its small size, low price, and ease of integration, system testing accuracy can be improved. For example, by integrating a micro pressure sensor and a micro temperature sensor to measure pressure and temperature at the same time, the temperature in the pressure measurement can be eliminated through on-chip calculations. Influence. Many micro sensors have been released, such as pressure sensors, acceleration sensors, silicon acceleration sensors for collision avoidance, etc. Embedding tiny pressure sensors in car tires can help save fuel by maintaining proper inflation and avoiding over- or under-inflation. Multifunctionality enables the sensor to detect one or more characteristic parameters at the same time. The smart sensor has intelligent characteristics because it has a special computer.
In addition, issues such as sensor response time and the interface between output and computer are also important research topics. With the development of electronic technology, the technology of automotive sensors will inevitably become more perfect.