Engineering Experience 4: Design a Small Solar Vehicle/Team PM8

Feb. 18, 2011
Cooperation Contract

Plan of Approach

Work Breakdown Structure

Gantt Chart

Mar. 25, 2011
Simulink

Design/Process Report

Calculations

Sankey Diagram

Engineering / Case SSV, Part II
Final Calculations

Sankey Diagram

Technical drawings: Chassis and Wheel Holder

Enterprising
Enterprising

External webpage: http://solarinternational.xavierziemba.com

Educating
Final Process Report

Final Design Description

The remaining components of this process report can be found on this page. The story of our design is summarized by the meeting notes below.

Meeting 1: February 15, 2011
At first all teams are formed by our teachers, this being done, every student verifies what team he’s in and sticks together with his other teammates.

Every member was present, except for Miengma, this is due to the fact that he’s been added to our team 2 days later.

After getting to know the other teammates we exchange our emails and phone numbers, we make agreements about how to keep in touch and exchange our files. We assign different responsibilities like team leadership or conference president and try to find a name for our team. Then we discuss our first assignment, which consists of making a Work Breakdown Structure, a Gantt Chart, a Plan of Approach and a Cooperation Agreement. We decide to work on little groups of 2 people on every document and share it with a software called Dropbox.

Meeting 2: February 22, 2011
Every member was present.

Our material, a motor and a solar panel, is handed over after a couple of seminars about the solar panel and how to do the calculations and similar stuff. Then we have a short meeting as a team where we discuss how to start and take the first steps to the building process of the SSV. We mainly discuss how to save weight and to minimize the drag of the chassis and the body of the vehicle. The idea comes up to position the solar panel in front of the body, in such a way it faces towards the sun, so we only have to take in mind the drag of the panel. We agree to make calculations about the optimal orientation of the panel towards the sun based on astronomics and the rotation of the earth. Also, we want to get the design software Solid Edge on our laptops by next week, so we could start drawing some vehicle parts and combine them. Finally, we ended our meeting by agreeing each teammember has to design a prototype for the vehicle, so we could compare different designs by next week, sharing our visions and stick the common parts together to form a vehicle every-one agrees with. We also received feedback about our first week’s assignments, and since the Gantt Chart and the Work Breakdown Structure didn’t fit to the expectations, we planned to ameliorate these.

Meeting 3: March 1, 2011
Every member was present.

First of all we compared the different designs everyone made, we quickly agreed our vehicle would have three wheels instead of four, because of different reasons most of the designs were three-wheeled cars. Basically, three wheels would reduce the weight of the cars, and the central wheel would help the vehicle heading forwards by using the rail on the rubber underground. Also, three wheels might require an easier transmission for the car, since we don’t have to power an axis with 2 wheels, but just 1 single wheel. About the materials to shape the body we thought of using plastics, they are cheap and light, easy to laser-cut. This way we would construct a triangular shape with at each corner a wheel, and in de center an adjustable pole to which the solar panel is attached. We’d rather avoid using the 3D printer in the FabLab because of the expensive costs. The tasks for next week are first of all calculating things resistance of rolling, losses, amount of sunlight falling on the panel, secondly to figure out what kind of transmission we will use and already design some parts in Solid Edge, and finally keep the blog up to date with the notes of the meetings. We divided the task so that each member has something to do for next week. Florian is responsible for the calculations, helped by Vantha, Hong and Miengma. The Solid Edge part will be achieved by Sven and Cedric with additional help of Jean. At last Xavier will take care of the wiki-blog, uploading the notes written by Jean.

Meeting 4: March 8, 2011
Every member was present.

This week we received a little feedback from our coach about the calculations we prepared. After that we figured out three things had to be done by next week: first, the calculations need to be corrected and finished. Second, a basic vehicle design should be completed in the CAD software Solid Edge. And third, we should start to explore Simulink and how it all works, so by next week we can start serious programming. We therefor divided the team into groups of 2-3 people who will take care of one of these three tasks.

Meeting 5: March 15, 2011
Every member was present.

First of all, we continued doing the assignments we agreed about last meeting: the Matlab team started the first steps to the completion of the Simulink project and the CAD team started designing the first basic parts of the vehicle such as the chassis, the solar panel and the motor. Aside from that, we figured we'd make most of our vehicle parts in Delrin plastic, so we ordered a 1m*2m plate of this plastic made by a specialized company. We also figured we would use a belt-transmission to connect the motor with the rear shaft, an appropriate gear ratio still has to be confirmed, since our gear calculations still need to be finished and controled by our coach. Finally, we made some sketches of the vehicle, so everyone could project his/her thoughts about it and thus making it easier for the CAD-team to start designing a prototype.

Meeting 6: March 22, 2011
Every member was present.

We basically continued working on the Simulink case, CAD-designs and the design report, keeping in mind our SSV1 deadline on March 25th. We gave our comments about on the first CAD-prototype, since there were still a few issues that needed to be changed, such as the position of the motor, and the shape and position of the panel-holder. We agreed we'd have everything finished 24 hours before the deadline, so there would still be a day to adjust the bad parts and check spelling mistakes.

March 25, 2011
SSV1 finished, however some documents were uploaded at the wrong place and sadly our coach considered this as a delivery past the deadline, which will cost us points in the final note.

Meeting 7, March 29, 2011
Every member was present.

We received some feedback about SSV1 from our coach. Our report design was a little too superficial, because we didn't add any relevant arguments, only pointless descriptions of the materials and parts we would use. The Simulink case was fine overall, only some graphs and calculations had a messy layout at times, making it hard to understand. Aside from that we received some useful advice about our transmission and parts. We agreed we'd all make an effort to purchase decent materials for the vehicle during the Easter break.

Meeting 8, April 26,2011
We brought together almost all the components required to make the SSV work today. Everything necessary for the SSV was present except for the bearings. The bearings were not present yet because they had not arrived from America. We ordered additional bearings from Igus in Germany in the event that the bearings do not clear customs in time.

May 3, 2011
The race took place today. Our SSV was capable of climbing the ramp.

Meeting 9, May 10, 2011
Because case SSV 2 is due at the end of the week, we had a brief meeting where we broke out tasks for each individual. These tasks will be completed tomorrow night such that there is enough time to reflect and revise.