CAN Newsletter magazine
The trend to more complex devices is ongoing. This is also true for sensors as reported in the latest CAN Newsletter magazine. Thus they require more sophisticated communication interfaces.
Any electronic control system comprises three parts: input, processing, and output units. Even very complex control systems with one or several embedded networks consist of these three unit categories. Inputs include measuring devices also known as sensors. These sensors are going to become more complex. Even a simple inclinometer is not more that simple. It needs to compensate not just temperature changes but also it should also consider accelerations and decelerations in some applications. This is sensor fusion. Of course, the sensor fusion applications for automated and autonomous driving are more complex combing cameras, radars, and lidars.
CAN technology, in particular the CAN FD protocol featuring a higher bandwidth and payloads up to 64 byte, is a good candidate for those more complex sensor systems. Besides, the carmakers and manufacturers of commercial vehicles including machines on wheels are driving sensor fusion. Another application field is service robots and collaborating mobile robots, which requires similar complex sensor systems. In battery-powered systems they need to consume as less as possible power. This means they should be light weighted.
The transmission of sensor data is essential for all control applications. End-users should not underestimate the robustness and reliability, which CAN communication provides. Additionally, the CAN hardware is available for very reasonable costs. The higher-layer protocols are well standardized (e.g. CANopen and J1939) and field-proven. CANopen specifies several sensor types by means of device profiles.
Sensors are the base of that what is called the Internet-of-Things (IoT). They provide the base for big data processing. CiA is developing standardized solutions to connect CANopen sensors to the clouds: The CiA 309-5 gateway specification is one, another one is the OPC UA compendium specification specifying the mapping of CANopen networks. Recently, CiA started discussion on this topic with the nonprofit SGET association and CiA is also involved in VDA’s IoT approach for body electronics in commercial vehicles.
In the September issue 2017 of the CAN Newsletter magazine the focus lays on sensors. The magazine contains the following articles regarding this topic: