Positioning and telemetry from ROV survey PS122/5_60-165 on 2020-09-04, survey 1

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，北极气候多学科漂流观测站（Multidisciplinary drifting Observatory for the Study of Arctic Climate，MOSAiC）考察中，遥控潜水器（remotely operated vehicle，ROV）的水平位置通过声学长基线（Long Base Line，LBL）定位系统（LinkQuest Pinpoint）测量。位置数据记录于SPOT.ON调查系统软件（OceanModulesTM）。轨迹经初始声学定位点平滑处理后，剔除了大部分明显异常值。位置采用浮冰固定的相对坐标系（X,Y），原点（X=0 m，Y=0 m）位于ROV作业孔处。基于至最近定位点的时间，引入位置质量标记："1"表示良好位置（定位时间≤3秒），"2"表示中等位置（定位时间>3秒且≤5秒），"3"表示较差位置（定位时间>5秒）。根据科学目标差异，质量标记为"3"的位置仍可能具有使用价值。ROV深度由集成压力传感器测量，并在预调查流程中校准为0（此时ROV顶部与水面齐平）。ROV姿态（横滚、俯仰、航向）通过搭载的惯性测量单元（inertial measuring unit，IMU，Microstrain）获取，该单元包含三轴加速度计、磁力计及陀螺仪。深度同时由ROV主电子舱内的压力传感器（Keller A-21Y，Keller AG）测量。