Tips for Use

The following tips may help you operate the USBL system with better performance, or diagnose problems if they arise.

1. For tracking, the X150 Topside Beacon and the X010 ROV Beacon must be submerged underwater. During operations, the X010 ROV Beacon will be deeper than the X150 Topside Beacon. Tracking performance may decrease the farther the ROV is from the X150 Topside Beacon, especially if the ROV is shallow.

2. Underwater Acoustic systems require line of sight be maintained between beacons to operate. Moving the X010 ROV Beacon around a corner of a pier wall or behind an acoustic "shadow" will result in performance decline or loss of tracking. Tracking will resume when the line of site between beacons is restored.

3. Units of measure can be independently specified in several locations in the PinPoint software. Make sure the units are selected correctly where applicable.

4. There are many settings that affect the fundamental operation and tracking precision. Make sure to use and follow the checklists to avoid missing a step or setting.

5. Geolocation of the ROV is computed by combining several measurements, including the calculated relative offset of the ROV from the topside station and the relative offset of the topside station from the GPS reference point. The GPS reference point may additionally be offset from a "logical" reference point, such as the operator station. An error in any one of these measurements can result in an inaccurate final geolocation of the ROV.

6. The system uses sensors that can be subject to permanent or transient local influences including GPS, acoustic and magnetic interference. An error caused by any one of these influences can result in inaccurate final geolocation of the ROV.

7. USBL beacons have IDs. Typically, they will be set to appropriate default values when the system is received. If for any reason the Beacon IDs need to be changed, note that these IDs are implemented at the hardware and software levels. The hardware level governs and the PinPoint software must be configured to match the hardware assigned beacon IDs. To change the hardware IDs the SeaTrac Tools program must be used. See the Initial Configuration section in the Appendices for more information.