Positioning and telemetry from ROV survey PS122/1_8-125 on 2019-11-19, survey 1@en

The horizontal position of the remotely operated vehicle (ROV) during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition between November 2019 and September 2020 was measured using an acoustic Long Base Line (LBL) positioning system (LinkQuest Pinpoint). The position was recorded in the SPOT.ON survey systems software (OceanModulesTM). The track was smoothed from initial acoustic fixes and cleaned for most obvious outliers. The position is in a floe-fixed, relative coordinate system (X, Y) with the origin (X=0 m, Y=0 m) at the ROV hole. A quality flag for the position is introduced based on the time to the closest fix with “1” indicating good positon (fix reached <= 3s), “2” medium position (fix reached > 3s & <= 5s), and “3” bad position (fix reached > 5s). Depending on the scientific aim, a position with quality flag “3” can still be useful. Vehicle depth was measured by the integrated pressure sensor and calibrated to 0 during pre-survey procedures, when the top side of the vehicle was at the same level as the water surface. Vehicle attitude (roll, pitch, heading) was measured with an onboard inertial measuring unit (IMU, Microstrain) with three axis accelerometer, magnetometer and gyroscope. Depth was measured by a pressure sensor (Keller A-21Y, Keller AG) included in the main electronics housing of the ROV.

2019年11月至2020年9月期间，北极气候研究多学科漂流观测站（Multidisciplinary drifting Observatory for the Study of Arctic Climate，MOSAiC）考察中，遥控水下机器人（Remotely Operated Vehicle，ROV）的水平位置采用声学长基线（Long Base Line，LBL）定位系统（LinkQuest Pinpoint）进行测量。该位置数据通过SPOT.ON测量系统软件（OceanModules™）记录。原始声学定位解算结果经过轨迹平滑处理，并剔除了绝大多数明显的异常值。位置数据采用以ROV投放孔为原点（X=0 m，Y=0 m）的浮冰固定相对坐标系（X, Y）。针对该位置数据引入了质量标记规则，依据距离最近一次有效定位解算的耗时判定：标记"1"代表位置精度良好（定位解算耗时≤3s），标记"2"代表位置精度中等（3s < 定位解算耗时≤5s），标记"3"代表位置精度较差（定位解算耗时>5s）。根据具体科学研究目标，标记为"3"的位置数据仍可能具备使用价值。ROV的深度由集成压力传感器测量，并在预调查阶段完成校准——此时ROV顶部与水面处于同一水平面，深度值校准为0。ROV的姿态（横滚、俯仰、航向）通过机载惯性测量单元（Inertial Measuring Unit，IMU，Microstrain）获取，该单元集成了三轴加速度计、磁强计与陀螺仪。深度数据由集成于ROV主电子舱的压力传感器（Keller A-21Y, Keller AG）测得。