This project is developing a device that can be installed on a walking path or trail, which will allow researchers to automatically collect information about trail users. The device uses a complementary metal oxide semiconductor (CMOS) sensor that detects shapes and colors as people pass underneath a unit suspended 12 feet above a trail. The device is designed to automatically distinguish between individual users so it can potentially do more than record total trail use. For example, the study will test if it can record whether trail users are dog-walkers or bicyclists, the number of individuals using the trail, and even how often an individual user passes by. The device is being designed with off-the-shelf technology so others can easily replicate it. Sharpe’s team is testing the accuracy of the system’s trail counts by mounting a video camera alongside the device and having researchers use the video to make trail counts.