Autonomous robotic deep sea lander


TURTLE is an autonomous robotic deep sea lander, which has been developed by INESC TEC, the Autonomous Systems Laboratory (LSA) of the School of Engineering of the Polytechnic Institute of Porto (ISEP), the Portuguese Navy Research Centre (CINAV), and the companies ply and A. Silva Matos Metalomecânica (the latter was the leader of the consortium). It is operating since 2015.

TURTLE is a hybrid lander, being capable of staying at the bottom of the sea for long periods of time, but also of autonomously relocating itself and surfacing for maintenance operations. It is also able to dive and ascend with high-energy efficiency, and its autonomous capabilities allow for reduced operational costs and flexibility.

TURTLE is the first deep sea robotic system fully developed at Portugal.



  • Vehicle type: autonomous robotic deep sea lander
  • Body materials: metal sandwich panels, syntatic foam, stainless steel
  • Deployment: four hooks for craning, and capability to be towed
  • Length: 1.9 m
  • Width: 1.6 m
  • Height: 2 m
  • Weight in air: 1350 kg
  • Power: rechargeable batteries (LiFePO4, 8 kWh, extensible)
  • Battery charge time: 6 h
  • Payload capacity: 200 kg
  • Payload interfaces/ports: ethernet, serial RS232/485, with underwater connectors


  • Maximum depth: 1000 m
  • Autonomy: 1 month
  • Relocation range: 500 m (without resurfacing)
  • Propulsion: variable buoyancy system (VBS), four horizontal and four vertical thrusters (all independent)
  • Degrees of freedom: 6DOF
  • Communications: underwater acoustic communications; Wi-Fi/RF/GSM and satellite communications at the surface
  • Navigation systems: DVL, IMU, USBL, mapping sonars, UW vision, GPS (pop-up and surface nav)
  • Modes of operation: transportation to or from the ocean floor, multiple ascend/descend movements and seafloor re-positioning


  • USBL
  • DVL
  • Multibeam
  • Pressure sensors
  • Altimeter
  • Video camera + lasers
  • SLS system
  • Seismometer
  • Acoustic pinger
  • Hydrophone to gather ocean sound data or launch alerts
  • Additional payload capability


  • Hybrid lander combining mobility with long-term presence in the deep sea
  • Autonomous positioning
  • Hovering capability without disturbing sea floor and water turbidity
  • Energy efficient technologies for ascent-descent operations
  • Untethered system (no cables sent to the surface)
  • Modular, light and pressure resistant mechanical structures
  • On-board processing and sensor data logging
  • Robotic technologies, enabling reduced maintenance and operational requirements
  • Increases human presence and observation capabilities in the deep sea



  • Transportation and deployment of materials and tools to the seabed
  • Communications and navigation support for underwater systems


  • Ocean observatories
  • Marine biology monitoring
  • Oceanography
  • Seismic and acoustic activity monitoring


  • Harbour protection
  • Border monitoring
  • Intruder detection and monitoring


Download file

Photos and videos are available at the Gallery.