How to install and use sensor plugin in cesium 1.9?
The Readme file for sensors explains how to install https://github.com/AnalyticalGraphicsInc/cesium-sensors.
Please refer to this thread regarding support https://groups.google.com/d/msg/cesium-dev/2FpDSXwDvVA/0Xt1Do3ymRkJ
Be aware that the official cesium-sensors plugin will not work with Cesium 1.9 (at least, not with rectangular sensors). If you look at the github page, there are some user forks that have fixed the issue that would allow it to work in 1.9+.