## **Lab Setup** ## **Components** - microUSV - Computer - Wireless router - USB Webcam - USB 3.0 Extension Cable - Camera Mounting Rig - Camera Calibration Target To configure a body of water, such as a laboratory tank, for use with microUSVs, there are three required components: a host PC with the CVSensorSimulator application setup, an overhead camera, and a wireless router.  The overhead camera is connected to the host PC and records images of the operating area. These images are processed by the host PC to extract pose and sensor data for each microUSV who's AprilTag is visible in a given video frame. This data is then sent over wifi to the microUSVs which execute their control logic based on the simulated sensor data.  *The above figure shows the Memorial University deep tank configured for use with microUSVs as described. The overhead camera is clamped to the I-beam above the tank using a flexible mounting arm and may be difficult to see due to its size. The host PC is not shown here.* To setup the lab environment: - Build the CVSensorSimulator application on the host PC (see [Software Setup](https://osf.io/k7a8p/wiki/12.%20Software%20Setup/) for details). - Connect the PC to a wireless network; the same wireless network as the microUSVs. - Connect the PC to the overhead camera. - Calibrate the camera. Follow the instructions for [Camera calibration With OpenCV](https://docs.opencv.org/2.4/doc/tutorials/calib3d/camera_calibration/camera_calibration.html) and copy the fx, fy, cx, and cy values into the config.json file. - Mount the camera above the tank and orient it normal to the water's surface. For best results, the distance from the camera to the water's surface should be less than two meters. The camera used for testing was a Logitech C920 webcam. This camera's default settings were not ideal: showing lots of motion blur and re-focusing frequently. To adjust these settings for a similar USB webcam install the **v4l-utils** package. ``` $ sudo apt-get install v4l-utils ``` List all connected video devices using the following command and note which port name is associated with the overhead camera. In the case of the test setup, this was **/dev/video1**. ``` $ v4l2-ctl --list-devices ``` Edit the provided [webcam_settings.sh](https://osf.io/nt86x/) script to match the video device ID shown by the **--list-devices** command. Note that these settings will likely need to be tuned for each individual setup due to the unique properties of each camera and different lighting conditions before running the script. ``` $ ./webcam_settings.sh ```