ROV grade in situ mass spectrometer (ISMS)

Project goal: in situ concentration analysis for e.g. H₂, CH₄, CO₂, O₂at seeps and vents as immediate guidance for sampling during ROV dives

Overview

The development of the new in-situ mass spec (ISMS) is a cooperation between MARUM and MPI-MM Bremen (Department of Symbiosis - Prof. N. Dubilier). The system is based on one designed to operate at hydrothermal vents (GirguisLab, Harvard University, US) and is suitable for deep-sea ROV deployments (up to 4000m), mainly from both MARUM ROVs QUEST & SQUID. Future deployments might also include CTD casts and/or an integration into mid- to long-term observatories.

Within this project, the initial setup (hardware components and software architecture) was considerably modified and by this, turning the instrument into a new prototype. The ISMS provides real-time information and guidance for water and sediment sampling during ROV dives. The in-situ MS quantifies dissolved volatiles of masses up to 100. It is suitable for water depths of up to 4000 m and for the analysis of fluids with temperatures up to 350°C. The in-situ MS was initially tested and deployed with MARUM ROV QUEST 4000 during cruises MSM109 and M190 on deep-sea hydrothermal vents. Although the deployments were successful, they highlighted the need for further improvements to make the instrument a powerful analytical tool. The necessary technical improvements were developed in the laboratories of MARUM and MPI-MM and were successfully tested under in-situ conditions during the equipment test cruise MSM125. The data and knowledge acquired during these cruises will be utilised to establish this payload as a standard tool for the MARUM ROVs SQUID and the new QUEST 5000. Additionally, the possibility of using such payloads on a smaller ROV system with a smaller deck footprint, crew, and logistical requirements compared to full-size work-class ROVs, will be highly beneficial to the scientific community.

Technical Specifications

Physical Properties

Weight in Air (kg): 103 kg
Weight in SeaWater (kg): 53 kg
Overall Dimensions (B x H x T mm): 1200 x 290 x 358
Device is pressure isolated (450 bar pressure housing) and needsno hydraulic interfacing

Power Requirements

Operating Voltage: 24V
Min Voltage: 18V
Max Voltage: 36V
Operating Current: 3.5A
Maximum Current (including startup): 5.5A
Power Return(V-) is isolated from Chassis (GND)

Data Requirements

Port Required: Ethernet
Data Bits: 8
Update rate: Continuous
Comments: 2x serial via ethernet (using MOXA ethernet converter within ISMS pressure housing)