Dive Operations
After all of the pre-dive checks and tests have been completed successfully, you are almost ready to commence the dive. But, there is one more issue to address that could affect the performance of the ROV. The ROV is designed to be operated in a near neutrally buoyant configuration, so the last step before launching your VideoRay is to check the buoyancy. For most operations, the buoyancy is optimal when the top of the float block is even with the water surface and the ROV is level. If the ROV is to buoyant or heavy, the vertical position may be hard to maintain or control.
Buoyancy Check and Adjustment
To determine if the buoyancy is correct, lower the ROV and at least 3 meters (10 feet) of tether into the water. You can lower the ROV by the tether - it will not hurt the tether because there is Kevlar in it. Observe the ROV in the water - it should not be floating too high or sink. It should also be floating level and not tipped to one side or pitched up or down. If the ROV floats too high, you will need to add some ballast weights. If the ROV sinks, you will need to remove some ballast weights. If the ROV is not floating level, you can change the locations of the weights.
The buoyancy can be adjusted by opening the skid pods and adding or removing the supplied ballast weights. To open the skid pods, turn the ROV upside down. Unhook the retaining o-ring on the end of the pod, and lift up on the pod. The weights can be added to or removed from the slots by hand. For most operations, the weights should be evenly distributed.
Buoyancy will need to be adjusted for use in fresh water versus salt water and depending upon whether accessories are used with the ROV.
Commence the Dive
Once the buoyancy has been adjusted the ROV is ready to launch. Lower it into the water and operate the controls to maneuver it.
- Start with the ROV on the surface and push the joystick forward slightly to make the ROV move forward. Move the joystick to the left or right to make it turn left or right. Get a feel for how agile the ROV is.
- Observe the video display as well as the ROV to become acquainted with the camera's wide angle lens and its affect on depth perception underwater.
- Once you feel comfortable with the horizontal maneuverability of the ROV, rotate the depth control knob to dive the ROV. Tilt the camera down as you dive so you can see towards the bottom. Rotate the depth control knob to bring the ROV back to the surface. Tilt the camera up as you surface so you can see towards the surface.
- Change the lights settings, and adjust the camera focus. If you have a manipulator, tilt the camera down so you can see it and open and close the jaws.
- As you get familiar with maneuvering the ROV, you can start to observe some of the on-screen displays including the depth, heading, camera settings and other data.
For your first dives, practice until you are comfortable operating the controls without looking at them and you are able to control the ROV with some precision.
See the Hand Controller section of the Equipment Guide for complete information about using the hand controller and see the Piloting section of the Operations Guide for more advanced tips on piloting the Pro 4.