如何将传感器连接到汽车网络

　　如何将传感器连接到汽车网络

　　有一个广泛的传感器通过车辆使用，从温度和触觉传感器加速度计和陀螺仪。本文着眼于传感器网络与有线网络（如LIN、以太网和以太网）的接口，在扩展温度范围和更高电压保护的汽车设计中。

　　现代汽车网络使用不同应用程序的协议组合。车辆周围的传感器越来越多地被广泛应用——从照相机的图像传感器到加热和乘客识别的温度传感器——意味着不同的传感器必须连接到不同的网络。

　　本地互连网络（LIN）是用于低成本的应用主要是在车身电子数据率通常是10到20 kbit/s，而控制器区域网络（CAN）是用于主流的动力总成和车身通信高达10 Mbit / s的FlexRay总线是高速同步数据通信等先进的主动悬架系统。大多数车辆设计者使用大多数总线来传输更高性能的网络，甚至50到100兆位/秒的视频，尽管在车上也有100兆位/ s的以太网网络来承载这些数据。

　　A key parameter for sensors to measure is temperature， as this can be used in many different ways to provide important information. The way the data is used， even for the same type of sensor， will require different bus interfaces. For example， an infrared temperature sensor such as the Melexis MLX90620 can be used as a ‘Thermal Comfort’ sensor in an automotive air-conditioning control system， but it can also be used for passenger classification and even for blind-angle detection. All of these applications would interface to different wired networks in the vehicle with different design requirements.

　　When the humidity in the car cabin is high and the temperature of the front windscreen is low， water vapor will condense on the glass， leading to an obscured view for the driver. The HVAC system can avoid this condensation by blowing dry hot air over the windscreen. For this， the system has to be able to detect condensation or even better， predict it. This can be done using IR thermometers， humidity sensors and external thermometers.