No matter how careful you are while driving, in the complex traffic conditions of Guangzhou, you may face minor vehicle collisions every day. As someone joked, "Even if you don't hit others, it's hard to ensure that others won't hit you." Therefore, as car owners, besides good driving habits and skills, it is also necessary to understand how to handle minor vehicle collision accidents.
● Pull over and turn off the engine: If your car accidentally scrapes another vehicle, immediately choose a suitable location to park. Engage the handbrake, cut off the power, and turn off the engine. At night, turn on the width indicator lights and taillights. On highways, place a hazard warning sign behind the car.
● Confirm safety status: Check the safety status of all parties involved. If there are casualties or injuries, call the police immediately. For situations not covered by the eight mandatory reporting scenarios outlined in the new Road Traffic Accident Handling Procedure Regulations, parties can opt to reach an agreement themselves for quick handling.
● Record damage details: Carefully inspect the vehicle's condition. It's best to carry a camera or phone with photography capabilities to document the scrape marks and overall vehicle condition. When taking photos, make sure both parties are present in the picture and take multiple angles including the front, rear, and collision points.
● Record basic information: Note down both vehicles' information and owner details, such as license plate numbers, driver's licenses, registration certificates, and insurance policies.
● Determine responsibility: Pay special attention to the responsibilities determined by the traffic police. Common scenarios include: failing to maintain safe distance leading to rear-ending, where the rear car is responsible; changing lanes without allowing normal passage for other vehicles, where the lane-changing car is responsible; at intersections with traffic lights, turning cars not yielding to straight-moving cars, where the turning car is responsible; at intersections without traffic lights, not yielding to vehicles from the right, where the non-yielding car is responsible.
● Vehicle appraisal and claims: First go to the insurance claims center for vehicle appraisal. During subsequent repairs, keep repair invoices.
With the development of electronic technology, the level of automotive electronics continues to increase. Traditional mechanical systems have difficulty addressing certain issues related to automobile functionality, thus they will gradually be replaced by electronic control systems. Sensors, as key components of automotive electronic control systems, directly impact system performance. Currently, a regular car has around dozens to nearly a hundred sensors, while luxury cars have even more. These sensors are mainly distributed in the engine control system, chassis control system, and body control system.
Engine Control Sensors:
There are many types of engine sensors, including temperature sensors, pressure sensors, rotational sensors, flow sensors, position sensors, concentration sensors, and knock sensors. These sensors are the core of all vehicle sensors. Using them improves engine power, reduces fuel consumption, minimizes exhaust emissions, and detects faults. Since they work in harsh environments like engine vibration, gasoline vapor, mud, and water splashes, their environmental resistance technical specifications must exceed those of ordinary sensors. The most critical performance indicators are measurement accuracy and reliability; otherwise, deviations caused by sensor detection could lead to the malfunctioning or failure of the engine control system.
Knock Sensor:
The knock sensor detects engine knocking or combustion noise under various operating conditions to prevent abnormal engine operation.
1) Temperature Sensors: Mainly detect engine temperature, intake air temperature, coolant temperature, fuel temperature, catalytic temperature, etc., converting them into electrical signals to control the timing and duration of the fuel injector needle valve opening, ensuring the supply of optimal air-fuel mixture to the engine and achieving exhaust purification effects. Practical temperature sensors mainly include wire-wound resistor type, thermistor type, and thermocouple type. Wire-wound resistor type temperature sensors offer high precision but poor response characteristics; thermistor sensors have high sensitivity and good response characteristics but poor linearity and low applicable temperatures; thermocouple sensors have high precision and wide temperature measurement ranges but require consideration of amplifiers and cold end processing.
2) Pressure Sensors: Mainly detect cylinder vacuum to control ignition and fuel injection; atmospheric pressure to control the air-fuel ratio during uphill climbs; cylinder pressure to control ignition advance angle; exhaust gas recirculation flow, engine oil pressure, brake fluid pressure, tire air pressure, etc., responding to relevant quantities. Currently, several types of vehicle pressure sensors exist, with capacitive, piezoresistive, differential transformer (LVDT), and surface acoustic wave (SAW) being widely used. Capacitive sensors have high output energy, good dynamic response, and excellent environmental adaptability; piezoresistive sensors are greatly affected by temperature and require additional temperature compensation circuits but are suitable for mass production; LVDTs have large outputs and are easy for digital output but have poor vibration resistance; SAW sensors have small size, light weight, low power consumption, strong reliability, high sensitivity, high resolution, and digital output characteristics, making them ideal sensors.
3) Rotational Sensors: Mainly used to detect crankshaft angle, engine speed, throttle opening, vehicle speed, etc., controlling ignition timing, fuel quantity, and injection time. Major products include generator type, magneto-resistive type, Hall effect type, optical type, and vibration type.
4) Oxygen Sensors: Detect oxygen content in exhaust gases, sending negative feedback signals to the fuel supply system to adjust the fuel pulse and bring the air-fuel ratio to theoretical values for ideal exhaust purification. Commonly used are zirconium oxide and titanium oxide sensors.
5) Flow Sensors: Measure air intake and fuel flow to control the air-fuel ratio. Main types include air flow sensors and fuel flow sensors. Air flow sensors detect incoming airflow to control electronic fuel injector spray volume, obtaining precise air-fuel ratios. Practical products mainly include Karman vortex type, vane type, and hot wire type. Karman vortex type has no moving parts, reacts quickly, and has high precision; hot wire type is easily affected by intake gas pulsation and can break easily; fuel flow sensors detect fuel velocity to calculate vehicle fuel consumption, with main products being paddle wheel type and ball circulation type.
6) Knock Sensors: Detect engine vibration and adjust ignition timing based on detected knock signals appropriately. Main products include magnetostrictive and piezoelectric types.
Chassis Control Sensors:
Chassis control sensors refer to sensors distributed in transmission control systems, suspension control systems, power steering systems, and anti-lock braking systems. Their roles differ in different systems, but their working principles are similar to those of engine sensors, mainly including:
(1) Transmission Control Sensors: Mainly include vehicle speed sensors, acceleration sensors, engine load sensors, engine speed sensors, clutch sensors, water temperature sensors, oil temperature sensors, etc. Information obtained from these sensors enables the electronic control unit to control shift points and torque converter lock-up, achieving maximum power and fuel economy.
(2) Suspension System Control Sensors: Mainly include vehicle speed sensors, throttle valve opening sensors, acceleration sensors, body height sensors, steering wheel angle sensors, etc. Based on information detected by these sensors, the system automatically adjusts vehicle height, suppresses changes in vehicle attitude, and controls vehicle comfort, maneuverability, and stability.
(3) Power Steering System Sensors: Mainly include vehicle speed sensors, engine speed sensors, torque sensors, etc. Using these sensors, the power steering electronic control system achieves lightweight steering operations, improved response characteristics, reduced engine consumption, increased output power, and fuel savings.
(4) Anti-Lock Braking Sensors mainly use wheel angular velocity sensors to detect wheel speeds, controlling brake fluid pressure when the slip rate of each wheel is 20%, improving braking performance and ensuring vehicle controllability and stability.
Body Control Sensors:
The primary goal of using these sensors is to enhance vehicle safety, reliability, and comfort. Environmental requirements are less stringent than those for engine and chassis sensors, and industrial sensors can be slightly modified for use. They mainly include various temperature sensors, airflow sensors, solar radiation sensors in automatic air conditioning systems, vehicle speed sensors in brake door lock systems, acceleration sensors in airbag systems, light sensors in brightness auto-control, ultrasonic sensors in blind spot alarm systems, image sensors, etc.
Trends in Research and Development of Vehicle Sensors:
Since sensors are crucial in electronic control systems, improving competitiveness in automobiles essentially equates to competing in sensors. Countries worldwide highly value theoretical research, application of new materials, and product development. Diamonds have good heat resistance and thermal stability; their surfaces start to carbonize only above 1200°C in a vacuum and above 600°C in the atmosphere. Using this characteristic, high-temperature thermosensitive sensors can be manufactured for temperature monitoring and control from room temperature to 600°C, suitable for use in harsh environments with high temperatures and corrosive gases, offering stable performance and long service life, usable for high-temperature measurements in engines. Additionally, diamonds exhibit high deformation rates at high temperatures, which can be used to create vibration sensors and acceleration sensors for high-temperature environments. Combined with other material membranes, they can serve as high-temperature, corrosion-resistant, and highly sensitive pressure sensors for vibration detection and measurement of engine and cylinder pressures.
Optical fiber-type sensors are receiving widespread attention due to their strong interference resistance, high sensitivity, light weight, small size, and suitability for remote measurements. Many mature products already exist, such as fiber optic torque sensors, temperature, vibration, pressure, and flow sensors.
While developing new materials, advancements in microelectronics and micro-machining technologies have led sensors towards miniaturization, multifunctionality, and intelligence. Miniaturized sensors use micro-machining technology to integrate micron-level sensitive elements, signal regulators, and data processing devices onto a single chip. Due to their small size, low cost, and ease of integration, they can improve system testing accuracy. For example, integrating miniature pressure sensors and miniature temperature sensors allows simultaneous measurement of pressure and temperature, eliminating temperature effects on pressure measurements through internal chip calculations. Many miniature sensors have already been developed, such as pressure sensors, accelerometers, and silicon accelerometers for collision prevention. It's rumored that embedding miniature pressure sensors in car tires can maintain appropriate inflation, preventing over-inflation or under-inflation, potentially saving 10% of fuel. Multifunctional sensors can simultaneously detect two or more characteristic parameters. Intelligent sensors, equipped with dedicated computers, possess intelligent features.
Additionally, sensor response times, output interfaces with computers, and other issues are important research topics. With the development of electronic technology, automotive sensor technology will inevitably become increasingly sophisticated. The above content is jointly released by the official website of Sanitation Garbage Trucks (http://www.clwlu.com/)|www_clwlu_com and professional garbage truck manufacturers (http://www.clwwcw.com/)|www_clwwcw_com. For more exciting content: