Team Vision for Detailed Design PhaseThe main items to be completed during this phase were:
- Creating electrical schematics in Eagle
- Fixing the crack on the hull
- Designing and mounting structure & steering system
- Finishing the assembly of small-scale boat
- Performing model boat tests
Electrical schematics for the Sensor/CPU board and Power Distribution board have been created. A commercially-available triple-channel DC motor controller (Roboteq FDC3260) was selected in place of designing a custom motor controller board, significantly reducing development and testing time. In regards to the boat, the crack in the hull was successfully repaired allowing for the float test to proceed.
The preliminary concept for the vessel equipment mounting framework has been laid out, however the design will change slightly once we obtain our solar panels. The design and for the steering system has been finalized, including CAD models and drawings.
Assembly of the small-scale boat has been stalled because the current design for the motor/pulley system the water would cause the pulley to slip and the spinning action would splash water back up which would harm the electrical components near by. Instead, we have a bevel gear system that will be located inside a PVC pipe to mitigate slippage. This resulted in the model boat tests being delayed.
Boat Status Updates
Hairline CrackUpon initial visual inspection of the boat, a hairline crack in the port pontoon was discovered. This did not appear to go through the thickness of the hull, but it was still a significant risk as the crack could extend in the future, allowing for water ingress into the hull. 3M Marine Adhesive Sealant Fast Cure 5200 (datasheet) was used to repair the crack, as it "forms a watertight, weather-resistant seal on joints and boat hardware, above and below the waterline."
No additional problems were found during the float test.
Prototyping, Engineering Analysis, Simulation
Payload Specification Updated
Above is the updated projected power consumption of the boat based on the maximum draw of all known components. The motors consume the most amount of power, therefore this system's power consumption was calculated at 100% (top left), 75% (top right), 50% (bottom left) and 25%(bottom right) of maximum draw while all others systems were kept at 100% power.
Above is the battery capacity needed to obtain 1-10 hours of Autonomy based on the Updated Payload Specifications.
Solar Analysis Update
An analysis PDF can be found here: Solar Analysis.pdf
Drawings, Schematics, Flow Charts, Simulations
Updated Top-Level Electrical Systems Architecture
Sensor Board Schematic
A searchable PDF version of the Sensor Board Schematic can be found here: SensorBoard_Rev1.pdf
Power Board Schematic
A PDF version of the Power Board Schematic is: PowerBoard.pdf
We will use a 1.5" x 1.5" T-slot frame to mount the electronic enclosures, solar panels, and steering sub-assembly.
- Still parallel linkage
- Revised tie rod design to increase robustness and decrease complexity
Risk AssessmentOur risk assessment hasn't changed from the previous phase. The risk assessment can be found here.
Bill of Material - Mounting
The Excel version of the Mounting BOM can be found here
Detailed Design ReviewDetailed Design Review Presentation
Plans for next phase
- Test plans for engineering requirements
- Adding detail to MSD II project schedule
- Finalize drawings for mounting and steering
- Near finalized BOM