, the user cantrigger the RaspberryPI to record video based on an external trigger. If it's an internet-connected PI, you can query another streamgage or other sensor and trigger that way. In the process of testing some other methods.
currently trigger the camera in 3 ways:
1. By a schedule (this is the standard approach—capture videos on some set interval)
2. Using an internet connection, by checking a NWIS web streamgage parameter against a user-defined threshold
3. Using a relay kit we distribute with a typical Raspberry Pi setup
4. We are working on using MQTT to do control and command so that the Raspberry Pi may be triggered from the cloud, or from other IoT sensors in the network.