基于CAN总线的高精度称重传感器节点设计

Design of high-precision weighting sensor node based on CAN bus

传统二次仪表式称重传感器是将Wheatstone电桥输出的模拟信号送到二次仪表,经放大、模数转换后显示输出,具有传输距离短,组网能力有限,二次放大会引入误差等缺点。这里将车载称重系统中的称重传感器信号直接数字化,并引入CAN总线,利用现场总线容错性强、通信速率高等特点,提高了车载称重系统的精度和数据通信的可靠性和实时性。设计了一个主控器节点和多个高精度称重传感器节点,并将节点直接连接到CAN总线网络中,实现了基于CAN总线的车载高精度称重系统的设计。

The traditional weighing sensor with secondary meter mode sends the analog signal output by Wheatstone bridge to the secondary meter,which will displayed and output after amplification and A/D conversion. It has the defects of short transmission distance and limited networking performance,and may bring in the error due to the secondary amplification. The weighing sensor signal in the vehicle-mounted weighing system is digitized directly. The CAN bus is introduced into the system. By means of the characteristics of strong fault tolerance and high communication rate,the precision of the vehicle-mounted weighing system,reliability and real-time performance of the data communication are improved. A node of the master controller and multiple nodes of high-precision weighing sensor were designed,and connected to the CAN bus network directly. The design of the vehicle-mounted high-precision weighing system based on CAN bus was realized.