Tuesday, February 24, 2009

Circuit Board Design Complete


The circuit board has been designed, completed and sent out for printing. The design has been greatly improved from last year's AUV. The new design has a smaller footprint and is more efficient on it's use of pins. With the new design we have also created an effective way of managing the wires to make the overall appearance much more professional and organized.

Camera box mk1mod2


The previously designed camera box foam enclosure was using 4lb/ft^3 weight foam. This presented the possibility of it breaking in some way. The new foam enclosure uses 10lb/ft^3 weight foam and has characteristics similar to a wood block.

Saturday, February 21, 2009

Camera box design

Many different solutions as to the creation of a structure for the inside of the camera box were devised. However, since it is hard to effectively glue anything to the plastic of which the camera box is made, a foam structure was carved. This stops movement by simply filling all of the free space within the box, and will help prevent reflected light within the box.

Tuesday, February 17, 2009

DVL

The new DVL is up and running. There are significant changes from last year's DVL but it will still provide the necessary, though less, data. However, this data comes in a different format than last year's DVL so the code will have to be significantly changed. Also, the DVL does not operate normally in air, going into a search mode that causes a very slow ping rate. On a side note, LinkQuest provides little documentation on their product and customer support can be frustrating, but entertaining, to deal with.

New Compass



Due to poor performance and a decaying lifespan we have sought a new compass to replace the old Honeywell that we have been using for years.

The new compass has improved versatility with a greater pitch and roll range as well as hard and soft iron calibration. The new TCM 5 compass was graciously given to us by PNI and we are looking forward to installing it on the vehicle.

Sunday, February 8, 2009

Through box switch

A test rig was constructed using an old Pelican case and an electromagnet from last year's team. First a hall effect switch was tested; in theory this switch will stop current flow when a certain density of magnetic flux is near it. Testing outside the box worked extremely well from all directions, but failed when connected to the test rig. The reed switch could be triggered through the test rig only using a stack of at least 4 rare earth magnets. If a stronger electromagnet could be found, I beleive that both could easily be triggered through the box. However, the hall effect sensor would be the way to go since the direction of the magnetic force does not effect its trigger.

Thursday, February 5, 2009

The Frame has been Fabricated

This week we finished the fabrication of the frame and it turned out practically identically to what we designed on the computer. There are still a few washers that need to be added and holes to drill which allow free flooding of the frame but the entire team is very pleased with the results.

Monday, February 2, 2009

Compass Calibration

Calibrating the compass has proved to be more of a challenge then expected because due to a saturation of magnetic fields in our lab building we cannot calibrate it in our lab.

I have another location but with the same results. I'm sending it to one last location for calibration and if we are still encountering magnetic saturation then the problem may be with the compass. The good news is that the roll and pitch measurements are accurate and reliable to +/- 80 degrees.