Latis II Underwater Remotely Operated Vehicle Technical Report

ABSTRACT
For the first time, a University of Maine
Mechanical Engineering Senior Capstone Design
group designed and built an underwater
remotely operated vehicle (ROV) and will
participate in the 2010 MATE International ROV
Competition. Four senior Mechanical
Engineering design students have worked on
preparing a prototype underwater ROV (Latis I)
and their final underwater ROV (Latis II) for the
competition. Missions included such tasks as
sensing and measuring sound waves, accurately
measuring fluid temperature, navigating
through an underwater cave and collecting
crustaceans and other materials from
underwater and returning them to the surface.
While Latis I provided much needed practice
and valuable insight into designing an
underwater ROV, Latis II was designed to
complete the missions outlined by MATE for the
competition. The UMaine ROV Team built two
identical four-degree-of-freedom (DOF) arms
with open-and-close grippers. To manipulate
the arms on the ROV the team also built two
control arms which provide feed-forward
control. Latis II has a custom-made upper body
structure machined from High Molecular
Weight Polyethylene (HMWPE) and a stainless
steel lower frame. There are six static thrusters
providing six DOF control, three cameras and a
holding net. Onboard control is achieved using a
Compact Rio (C-Rio) which receives signals from
a space navigator joystick and an Arduino
2
LATIS II
TECHNICAL REPORT
micro-controller that translates information
from the control arms.
TABLE OF CONTENTS
Abstract ....................................................... 2
Budget/ Expense ......................................... 3
ROV Electronics ........................................... 4
Main Controller ....................................... 4
Thrusters ................................................. 4
Servos ...................................................... 4
Sensors .................................................... 4
Custom Circuit Boards ............................. 4
Surface Controls .......................................... 6
Main Controls .......................................... 6
Arm Controls ........................................... 6
Power Supply Box ................................ 6
Software ...................................................... 7
Design Rationale ....................................... 11
Missions ................................................. 11
TASK #1 – Resurrect HUGO................ 11
TASK #2 – Collecting Crustaceans ...... 11
TASK #3 –Sample New Vent Site ....... 12
TASK #4 – AGAR Sample .................... 12
ROV Design ........................................... 12
Frame..................................................... 12
Arms ...................................................... 13
Tether .................................................... 14
Thrusters ............................................... 14
Cameras ................................................. 14
Challenges ................................................. 15
Troubleshooting Techniques .................... 15
Lesson Learn/ Skills Gained ....................... 16
Future Improvements ............................... 17
Loihi Seamount ......................................... 18
Reflections................................................. 19
References ................................................ 20
Acknowledgements ................................... 20