Engineering Experience 4: Design a Small Solar Vehicle/2012: Team PM14

Introduction

The Engineering Experience 4 (EE4) for students who major in Electromechanical Egnineering at Group T is bulding a Small Solar Vehicle (SSV). The school provides a solar panel and a DC motor for each team. Every team should design and assemble thier own SSV and take part in a SSV race at the end of this semester.

Team: Basic Information

Team Name

Our team name is Super Solar Speed, which means that our goal is making the most innovative and fastest SSV in this project.

Team Members

• Atefeh Hosaini (team leader)
• Koenraad Vanhoutte
• Lu Hongyang
• Ji Luxi
• Mao Huitan
• Tam Sirikul
• Michiel Celis

General Information

Cooperation Contract

This is to explain the basic information of the team and formulate some rules while working.

Work Process

Week 1

The coaches introduced the project basically and divided students into different teams. Our team finished Cooperation Contract, Plan of Approach, WBS and Gantt Chart on Friday.

Week 2

A new team member (Michiel Celis) joined in our team. The coaches illustrated the general information about the solar panel and DC motor and gave these stuffs to every team. We determined the m value (diode factor) of our solar panel.

Koenraad Vanhoutte

Koenraad found a transmission system without gears, named Continuous Variable Transmission (CVT) specifically. This kind of system can solve the problem of the interrupted transmission while changing gears and any probable gear ratio can be chosen.

All these researches will be discussed next week.

Week 3

Michiel found a holder of GPS to support the solar panel. The device can attach the solar panel by air pressure. The greatest strengh of this device is that it is very flexible so that is can rotate into different directions. In this way we can improve the flexibility of solar panel to make it suitable for any height of the sun.

We discussed the work that was done lask week. We will order three or four wheels and several bearings from the website that Wanja found.

In the seminar the coach introduced something about gear ratio. We will use Matlab to calculate what gear ratio we will use.

We decided develop two projects in parallel, the normal gearbox and the CVT. The better one will be used.

Week 4

According to the requirements of Case SSV Part 1 and Case Simulink, we divided the total tasks into different parts and distributed them to every team member. These tasks are theoretical and hypothetical. When it comes to the practice, some data might be changed.

We designed the frame of our SSV. The basic idea is using triangle frame since we will make a three-wheel car. The bearings will be set at the altitude of the triangle and at a line which is parallel to the base of the triangle. In this way we can fasten the frame and the holder of solar panel can be fixed on this frame. Three wheels will be connected to three vertexs of this triangle frame. Koenraad has designed this frame on a software afterwards.

Week 5

The seminar of this week is given by Marc Lambaerts from Fatlab and we knew how to contact Fatlab to take some useful materials for the SSV. Besides, someone from the Umicore Solar Team gave us a introduction of the Umicar.

The basic tasks of this week are still Case Simulink and Sase SSV 1. We distributed the total tasks to everyone in detials. Tam,Wanja worked on gear ratio. Mao and Hongyang woked on the Sankey Diagram. Luxi focused on the process report. Koenraad,Machiel and Atefeh paid more attention on the Matlab-Simulink. We tried our best to finish every report. Next week is the deadline of these two cases and then we are going to start Case SSV 2, which is building our SSV in reality.

Week 6

This week we have to finish two important reports, Case SSV Part 1 and Case Simulink. Everyone works hard on his or her own part, especially Tam, Atefeh and Wanja. Some problems happen to the Simulink, they spent a lot of time to solve these problems. Finally we finished everything successfully and the final version of gear ratio is 9. Based on this, we modified our Sankey Diagram report and make every report correspond to each other.

There was no seminar Tuesday. The coach Tan Ye told us some information about these two cases' reports and the individual test after the Easter holiday. From next week on we will bulid our SSV in reality and connect Fatlab for some help. The case SSV Part 2 will be started, too. The leader divided the tasks to everyone basically.

Week 7

Due to the analysis of the solar panel, there was a "optimal point" in the current-voltage diagram, which can provide the maximum power to the car. However, we could not insure that the vehicle was work at this point in reality. In order to make sure that the car can work at this "optimal" region, we looked for the help of Prof.Bienstman on Friday, who introduced some related theories briefly to us and offered a PCB to us, which could be useful in our SSV building.

Wanja is in charge of this mainly and we all can assist him.

Easter Holiday

We did our EE4 project at Fablab the first week of Easter holiday. Koenraad designed different kinds of gears according to the calculation, using some hard plastic as material, which was waste in Fablab.These gears look very suitable for our car, both for the shaft of the motor and the bearing. The connection of gears are tight, hope that they can work well for the car.

We use some aluminum bars to make the frame, depending on what we drew in the computer before. The frame is very strong and stiff. And it is quite light. This frame is perfect for our SSV.

Week 8

There was a individual text on Tuesday, which was a theoretical test about Matlab (Simulink) and SSV Part 1. We can use each team's report as references in the test.

Koenraad made a fantastic "DC-motor holder" for our SSV. This holder can be attached to the frame perfectly tightly. And it is not cheap, of course. We assembled bearings and three wheels, which are from Australia, to the frame. Besides, we attached the base plate of the solar-panel-holder to the frame, too. So far the basic model of our SSV was accomplished.

Week 9

The seminar that was given by Pauwel Goethals was about the technical drawing. After that, our coach gave us feedback about the test last week and our first report (SSV Part 1 and Simulink). He introduced what would have to be done in the future, especially SSV Part 2 and some significant deadlines in the schedule. And the track that will be used in the final race is available to test the car.

We made the guiding systems of our car in the lab Module 7. They are four short bearings that are sticked to the vertical aluminum bar in the frame. for the sake of leading the car run in a straight line. We tested our SSV for the first time on the track, and the friction between the guiding system and the track was very big, even the car could not slide down. We have to change the guiding system. What's more, the gears did nit match the car exactly, we had to use other materials to make gears.

Koenraad used some woods to make gears, and they worked better than the plastic ones. In the morning of Thursday, he brought all kinds of gears to school. We did a new guiding system and glued every parts which were done until now to the frame again. We used a battery as power supplier for our car and tested it again. This time the car worked very well, both the guiding system and the gear box. The car only took 6 seconds to finish the whole 14-meter track.

Week 10

There was no seminar Tuesday since there was a holiday of Labors Day.

Last week the coach said the calculation in Sankey Diagram is not correct due to a wrong simulation in Matlab. The parameters we set in Matlab were not correct, such as the radius of wheels is 27 mm instead of 54 mm, and parameters were not consistent in different files. After several trials, we got the correct simulation finally. The optimal gear ratio is 5 instead of 9,which was got preciously. But it is too late to change the car... But anyway, the Sankey Diagram is correct now.

Another problem was happened to the car. One of the short bearings, which was a part of guiding system, was lost. We had to change the design of the guiding system. Koenraad, Mao and Tam did this in Module 7 lab on Friday afternoon. And the car is pretty strong now.

Every team member is working on his or her own part of the report SSV Part 2.

Reports

SSV Part 1

Here is the report of SSV Part 1.