Page 1

DECEMBER 2016/JANUARY 2017

TÉCNICO SOLAR BOAT

NEWSLETTER TÉCNICO SOLAR BOAT

THE END OF A GREAT YEAR Looking back on this year we find ourselves enriched with knowledge and hands on learning that this project offered us. 2016 was the year of conceptualising, 2017 is the year of construction and competition. 2017, we’re ready!

HULL For the hull section of the project, 2016 was a very productive year. The team spent the year learning about all the design methods and applying them to our current hull. However, its not all about the design as the

construction itself imposes a lot of difficulties which must be dealt with at the design stage. The final product, our hull, is a combination of theoretical results with practical knowledge which sometimes comes from long meetings with some of our sponsors. Starting by the hull itself, the first challenge was to decide what type of hull to choose: a monohull, a catamaran or a trimaran. Initially we were

set to design a catamaran; however, after a long deliberation, we decided that a trimaran in which the side floaters only touch the water in tight manoeuvres was a better solution. This way allows us to have a lighter boat than the initial catamaran and with a superior performance in terms of resistance. The floaters will help cornering and with the stability rules set by the competition. Accordingly, this design !1


DECEMBER 2016/JANUARY 2017

permits better and more efficient hydrofoils configurations. We faced a tough challenge to decide on the hull form as there is no method that guarantees the best shape. Our trimaran resulted from an iterative process. It started by seeking external opinions followed by a full parametric study that enabled us to understand which dimensions and form coefficients were important for our case. Finally, the fine adjustments were produced using CFD (Computational Fluid Dynamics) analysis which, with the computers we had available, took several days to obtain viable results. The team also dedicated a lot of their effort and time in the design of the production molds. Bare in mind that since the boat will be built in pre-impregnated carbon fibers, that must be cured at high temperatures, great caution must be taken with all the material selection for the construction. Due to the complicated chemistry of the resins used and the materials reaction to heat, the materials were carefully chosen regarding their properties and availability on the market. One of the major keypoints of our design is based on the optimization of all the structure in composite material in order to reduce weight. This is one of the

TÉCNICO SOLAR BOAT

most important factors that allows the solar boat to have a better performance. The weight also plays a very important role on the hydrofoil design which is currently being developed by the Transmission team. Finally, with de hull design concluded, we’re now focusing our efforts in the display of all electrical components, the development of the battery box, the drag/velocities curves (using CFD), the manufacturing of the watertight junctions and lastly minor structural parts.

At the beginning of 2016 we started conceptualising a trailer to carry our prototype and future vessels. The development of the trailer was a tough process that took about 4 months. Unfortunately, as time went by we realized that we were going to have legal issues if we built it ourselves. Therefore, the solution was to find a company that was willing to develop a trailer with the requirements needed. As announced in our last Newsletter, we managed a partnership with the company TONIAUTO who will build our trailer!

TRANSMISSION Throughout 2016 the Transmission team worked hard in order to conclude the design phase of the boat’s systems so that we can start fabricating these as soon as possible this year. The project of some systems such as the propulsion column and the direction system have already been finished and are currently being manufactured.

Probably the most challenging part of this area was the design of the hydrofoils, this system required much more knowledge than any other we’ve developed so far. Not only the dimensioning of the foils is difficult but also their construction. We’ll have good news about this soon! Although our year turned out quite alright, it’s important to mention that all the systems developed have some dependencies on other areas. As so, any minor alteration in a area may influence the remaining areas. Unluckily, this !2


DECEMBER 2016/JANUARY 2017

happened with our cooling system for the batteries. The project was progressing well until early November, when the electrical propulsion area discovered new batteries with distinctive properties: they didn’t waste nearly as much power per cell. We doubted whether if the cooling system was even necessary after this change, a proposition we’re still evaluating.

ELECTRICAL PROPULSION The start of the Electrical Propulsion area was a rocky one. We had little knowledge on how to implement such a system (an energy autonomous system) and the various existing restrictions of developing an electrical powertrain. Starting with the generation of electrical energy, we sought solutions ranging from rigid panels to flexible poly-crystalline panels without knowing what the trade-offs were. There were also many doubts on whether MPPTs were a must

TÉCNICO SOLAR BOAT

for our system or if a basic solar charger was enough. We now find ourselves confident of our solution. We are planning to connect a solar panel with 42 cells in series with a solar panel with 36 cells (total of 237,5W) in order to connect to one GENASUN MPPT, repeating this configuration 4 times and connecting all the MPPTs in parallel. The battery and BMS module was another hard choice for us. From the start we were focused on a certain cell topology, LiFePO4, only to find out that Li-ion would benefit us - lower cost and lower weight. There was uneasiness in changing our topology because Li-ion cells are more dangerous but since we grew as a team we could make this decision confidently. As for the BMS, we had our eyes on the Orion BMS for its small size and cost. Seeing as this is a simple electronic device, we took our chances at developing our own. Nevertheless, it must be a reliable system to insure the safety of our skipper and our project. Thus great attention

is being put in the various components we can choose and design of the circuit board. We are happy to announce that 2016 ended with a finished prototype of our BMS and we welcome this new year to test it!

The motor was the first piece of the puzzle. We knew what distances and autonomy were demanded by the competition. As so, we made an informed decision on the possible power our vessel should use to travel at our desired speed. Multiple simulations were run, from varying the sun radiance to hull specifications (wet area and drag coefficient) to the global system efficiency (various propellers). Our next challenge was then to ensure the safety of our electrical system and the powertrain. A global kill switch was projected but seeing as this is a feature of paramount importance there still is some research to be made in order to insure our system is fully protected. Finally, our data transmission sub area is to be congratulated. Besides helping with the development of the BMS, they completed the skipper's

!3


DECEMBER 2016/JANUARY 2017

display and advanced a lot of features that were set to be implemented in our boat, such as setting up a database in which all the boat's parameters are displayed (battery temperature, PV panels power output, battery current, …). Overall, we close this year with a very positive balance and we came from very little to a solid electric project!

MARKETING & LOGISTICS Let’s start off 2017 the best way possible announcing our most recent sponsor, NAUTIBER. A company that’ll provide us fiberglass, required for the construction of the molds!

TÉCNICO SOLAR BOAT

The Marketing & Logistics team summed up a total of 29 partnerships in 2016! Partnerships with great companies all over Europe. We were able to win two financial prizes of 2000€ from Caixa Geral de Depositos, at CA2ECTécnico. This year was also marked by our Crowdfunding campaign, which raised a total of 1518€ thanks to 43 supporters.

We were also part in events like Entrepreneurship and Tecnology Week, MecanIST, Naval Conferences, JobShop, Sample of Universidade de Lisboa and Nauticampo. A great thank you to these organizations. We would like to take this opportunity to thank all the companies and supporters for allowing us to be one step closer to our final goal.

Our project was mentioned in a few magazines and newspapers such as Valores Próprios Magazine, Jornal Notícias do Mar, Marinha Magazine, Jornal da Economia do Mar and UM Magazine! Thank you for giving more people the chance to get to know our project!

!4


DECEMBER 2016/JANUARY 2017

TÉCNICO SOLAR BOAT

This project is sponsored by:

www.facebook.com/tecnico.solarboat
 tecnico.solarboat@gmail.com !5

Newsletter December 2016 / January 2017  
Read more
Read more
Similar to
Popular now
Just for you