We spent the entire lab brainstorming different types of experiments that we can make a lab out of to give to students. We had a difficult time coming up with experiments that could be done over one long engineering experiment period or three short lab experiments. We all decided that we rather create a longer experiment rather than three short lab experiments. That's how we came up with the different concepts.
For week one these were the constraints that were important in the different concepts that we came up with.
Constraints:
1. Age of experimenter
2. Cost of experiment
3. Time constraint to complete the task
4. Complexity of task
5. Level Math difficulty
6. Supplies needed
7. Safety of student/teacher
8. Lesson has to be learned
9. Area of room experiment is conducted in
10. Number of variables
Concepts:
1. Loop-de-loop
2. S.O.S CAD Design
3. Wind Turbine
4. Catapults
5. Water Filter
Week 2: Choosing a Lab Topic
During our week two design lab, the team was instructed to narrow down our design lists as well as discuss our designs with two other teams. Upon sharing our three designs: loop-de-loop, catapult, and solar energy (wind turbines) the teams were able to give us feedback on how challenging each seemed to be as well as wanting a full explanation about the audience of each. After our discussion, the team was able to come together to understand how each design would encounter certain problems as well as their benefits for the high schoolers. As a team, we were then able to complete two iterations of the decision matrices to understand in what kind of environment each project would thrive. We based our scaling on the safety of the project, the group sizes, the level of education needed to complete the lab, the skills needed for the lab, the cost of the lab, the time of the experiment, the overall objectives of the lab, the constraints to the lab, and finally how user friendly the labs are. Upon creating two iterations we decided that the wind turbine would give the group and the students completing the lab the greatest learning outcome out of all of the labs that were brainstormed.
Decision Matrix: Sensitivity Analysis
In weeks 1 and 2 we started off with the idea that students will create a wind turbine by connecting circuits to motors while dealing with open wires. We never considered the safety of that idea or the prior knowledge students may have about circuits and electricity. From the other groups comments we were able to simplify the original idea so that the project will be safe and user friendly. We concluded that instead we will provide battery holders that are already wired to rocker switches so students won't have to deal with connecting wires and expect how to do it.
We concluded what exactly needs to be changed so the students can participate in our lab. This helped us figure out what materials we need to provide and also helped us finalize the material list as well as purchase the correct ones for the prototype. Prior to knowing exactly what materials we needed, our group researched certain parts as well as the cost for larger quantity orders. Upon looking at multiple websites we decided that buying certain products in groups and larger quantities would allow for a lower cost. We also decided that constructing a pin out of 3D printed material would be more beneficial than buying manufactured clips for the mounting of the blades to the DC motor.
Materials Needed
Rough sketches of what the parts that are needed in order to build this wind turbine. Included are the dimensions so we you can get a rough idea on the size of this project.
Below is the front and upper-corner view of the windmill base and at the top indicated by the arrow is where the motor will be sitting that the blades (shown below the windmill base) will be attached to.
Decision Matrix: Initial Analysis
Decision Matrix: Sensitivity Analysis
Week 3: Constructing a Plan
This week in lab, we were able to take into consideration the comments provided by the other groups. From these comments we then were then able to decide the correct timeline for the project. Along with the timeline we took the comments and used them to able to finalize our overall project. Finalize our project meaning the idea, skills that will be learned, and what the Wind turbine lab will have the students do.In weeks 1 and 2 we started off with the idea that students will create a wind turbine by connecting circuits to motors while dealing with open wires. We never considered the safety of that idea or the prior knowledge students may have about circuits and electricity. From the other groups comments we were able to simplify the original idea so that the project will be safe and user friendly. We concluded that instead we will provide battery holders that are already wired to rocker switches so students won't have to deal with connecting wires and expect how to do it.
We concluded what exactly needs to be changed so the students can participate in our lab. This helped us figure out what materials we need to provide and also helped us finalize the material list as well as purchase the correct ones for the prototype. Prior to knowing exactly what materials we needed, our group researched certain parts as well as the cost for larger quantity orders. Upon looking at multiple websites we decided that buying certain products in groups and larger quantities would allow for a lower cost. We also decided that constructing a pin out of 3D printed material would be more beneficial than buying manufactured clips for the mounting of the blades to the DC motor.
Materials Needed
- DC Motors
- AA batteries
- Cardboard
Rough sketch of what the final product/deliverable will look like, with the parts labeled.
Week 4: Objectives, Pitch, Updates
In today's lab we discussed and presented the three objectives of our project. We concluded that one objective is students will learn and use the engineering design process in order to develop and construct this wind turbine. They will learn the process of planning, designing, sketching, and constructing in order to complete this lab. Another objective that the students will learn from this lab is the understanding on how energy is converted to AC and electricity. With this lab while the students construct their wind turbines and actually get it to run, they will be able to see how the windmill picks up and energizes the motors. This will then power the phone and charge it. Lastly, the students will be able to have experience with the different kinds of engineering. During this lab they have the opportunity to develop a project that involves mechanical engineering and electrical engineering. During the construction of the whole system is a part of mechanical engineering and dealing with the set up of the motor and wires is a part of electrical engineering. The focus of this lab was to get the students familiarized with concepts from each of the STEM subjects.
Updated Materials List:
- DC Motor
- PCB Board
- Cardboard
- IOD fuse
- Sister USB
- Capacitor
Below is an updated rough sketch of the parts that are needed to construct this wind turbine.
Week 5: Designs and Manuals
During this lab, our team concluded that some changes needed to be made to the final product. We saw that we had to change where the motor is placed, the strength of the motors (volts), and the shape that the blade like propellers will look like.
In the previous design we had the motor separated from the cardboard structure base, however we concluded that instead we would cut through the cardboard structure and place the motor in it instead. For the strength of the motor we found that in order to charge a phone we needed a stronger voltage motor. So we had to go from a 6V DC motor to a 12V DC motor which was an easy fix. For the propellers we found that if we placed a restraint on them when the students build it, more wind will be picked up and will charge the phone. Originally we had regular straight up blades but we found that if the bottoms of the blades were curved in at the ends it'll pick up more wind.
This week also allowed us to start understanding and researching information to put into our lab manuals for the instructor as well as the students. We were able to find a couple examples of what a lab manual for an engineering project should look like. These sources gave us the ability to identify and understand what we needed to supply to both the professor and the students.
Week 6: Feedback
In today's lab we discussed our idea and went through the entire process with the lab supervisors and professors. During our discussion we had difficulty getting across our overall end idea for what the students would be learning. The professors told us that based on our objectives and short little summary of our project, we were combining two different kinds of engineering into this lab and being a three day duration lab it'll be hard to complete. So they suggested that we decide to focus more on only on one type of engineering. So we decided that we were going to go more towards mechanical engineering. But we realized that even though we choose to go with the mechanical aspects for this lab, our lab can be changed to deal more with the electrical aspect of engineering (which will be explained in the teacher's lab guide/manual). Whether we wanted the students to deal more with the electrical or mechanical point of view, one of the main concepts/objective that should come out of this lab is understanding the engineering design process. Along with the engineering design process we wanted the students to learn more about how engineering is applied to everyday life situations. Lastly, we wanted the students to understand the importance and understanding behind renewable energy.
We started to change some of the tasks that the students needed to do and the overall plan of our lab. Instead of having the duration of the three days designing a wind turbine, we plan to have on day one brainstorm, day two constructing, and day 3 be testing/final deliverables. Since we are going with the mechanical path for this lab we are going to have kits that include the PCB presoldered with the iods and capacitors. All the electrical part of this lab will already be completed and assembled together in the kit. On day one we want to focus more on the students building an understanding of how renewable energy is produced and what it can be used for. This day will explain the electrical part of the lab as well. After a clear understanding of this lab students will then begin to brainstorm ideas of for their windmill and start creating rough sketches of what their final deliverable will be. During this process they will be researching and looking at different types of wind turbines and which are the most successful in picking up wind energy. On day two they will transfer their ideas and rough sketches into the building process. They will take their rough sketches and actually build them. The majority of this day will be constructing their projects. On day 3 testing will be done. A fan will be provided for them to test their wind turbines, and at the end they should be able to present that their wind turbine can successfully charge a phone. We understand that the construction of their wind turbine may be longer than a day and possibly roll over to the third day, but that gives the students a lesson to be learned which is time management. The students will have to realize that they need to be able to get something done and figured out on a short period which allows them to experience how real life projects will be like.
After finalizing our plan for our wind turbine lab we were able to start and focus on what we expect the final deliverable should be like. We were able to focus more on what students will be doing in this lab and create examples for it. This allowed us to create rough sketches of the parts that the students will be doing and constructing in this lab. We then created a 3D representation of what they will look like in CAD, as shown below.
Below is the front and upper-corner view of the windmill base and at the top indicated by the arrow is where the motor will be sitting that the blades (shown below the windmill base) will be attached to.
Below is the front and upper corner-view of the example blades that will be shown to the students as a guide on what their blades should look like. This is just an example that we created however, the students are free to create any type of blade they want with the exception of following our constraints
Week 7: Lab Manuals
During week 7's lab we completed a rough draft of a teacher's and a student's lab manual for the wind turbine lab. We had a difficulty time figuring out what we should place into our student's lab manual but we went with the basic components like: introduction, background, objectives, materials, procedure, post lab questions, and a conclusion. For the teacher lab manual we also had a difficulty time writing it up as well because we kept writing it as though we were giving it to a student and telling them what to do for the lab. We had to spend a lot of the time changing up everything that was written and we also had to add a lot of side notes for teacher guidance. The teacher lab manual also consisted more of factual and background information because like said last week, on day one its background information and brainstorming. So in the teacher manual we had to include a lot more in depth detailing and explanations so they can give the students a clear understanding. We struggled a lot with this part because we are so used to being given the lab manuals and performing the lab rather than being the one constructing a lab manual for a lab to be done by others. That was the most challenging part. But good news was when we broke up into groups and gave our manual to a different group to read they were able to get at what our lab was and how to preform the lab. However, they did give us feedback on what to improve and they said for the final lab manual we should include more about the back ground knowledge and fix the procedure a bit so it doesn't basically say put this with this then do this. They told us to be a bit more detailed and we could include some side notes like the reason to do it this way or background information on it. Other than that they though our rough draft for a lab manual was fine.
Aside from the group to group review of lab manuals, we also went and began to construct a prototype of the wind turbine to see if the results are due-able. We had a difficulty time figuring out the sizing of the windmill base. We had to keep in considerate that the wires that connect the motor to the PCB board were only able to stretch 5 inches and because the motor is sitting on top of the windmill base we had to make the height smaller. For the blades of the windmill we were stuck on what types we wanted to make. Ideally we had in mind to create blades that curve at the bottom that way more wind can be picked up but we couldn't find a way to get the cardboard to curve like that. So we needed to find ways to make that better. Below are pictures of rough constructions of the windmill base and blades below. They are not the best looking but it will be cleaned up.
Week 8: Assembling (Prototype)
In this week's lab we spent a majority of the time trying to assemble a cleaner and better prototype than the one made last week. We wanted to remake this prototype of the wind turbine so it can be used to display a rough idea of what the final deliverable should look like. Also we needed to actually preform this lab so that we can see if everything works and in the end the results are presentable. So we went through the lab and began to construct the parts to the wind turbine neatly and with more thought. We started out by building the windmill base out of cardboard with measurements and making neater cuts. We then cut out triangles for the top of the windmill base that way you get it shaped like an obelisk. But after we cut the pieces out of cardboard and assembled it without the glue we realized that we can simplify this structure. This way the motor is more stabilized and supported. So, instead of the obelisk shaped windmill instead it'll just be a cuboid.
Then we remade the blades and we stuck to the idea and structure we constructed in week 7 but, we just cleaned it up a bit. The center dot is where the shaft of the DC motor will go. we placed it on the DC motor and started the fan up and saw that only the blades/propellers were moving and not the rotator coils in the motor (which is what generates the electricity). So we had to find a way to get the cardboard blades to turn the rotator coils that way the electricity can be generated. We decided that if we place hot glue on the shaft and the cardboard it'll mold into one thing and when the wind blows the blade the shaft will revolve in a circle. We did that and in our favor it worked. We then worked on a CAD design for a base that we will be 3D printing. This base will be made to hold the windmill base and protect the PCB board. The sister usb charger will simply come out of this base and sit right on top. Below is the CAD design of our base for the entire wind turbine.
We ideally was going to 3D print this piece however we decided to laser cut it because it'll be faster and cost less. We laser cut the pieces out of wood and then glued them together and ended with a box (shown below).
Week 9: Final Touches
In today's lab we spent a majority of the time putting the final touches on our prototype. We constructed and tested our prototype. On our first test we saw that the blades fell right off so we reglued them, but we saw that once the blades were in place and designed to pick up the most wind. We saw that it wasn't spinning the inside generator. We realized that we needed something else that the blades connected to. From short and quick brainstorming we saw thought of a bottle cap. We glued the blades to the soda bottle cap and punctured a tiny hole in the center of the soda cap. we forcefully slid the shaft of the motor through the hole and tested it again. We saw that the bottle cap spun the inside of the motor. We were very satisfied and shocked that this quick adjustment actually worked. We expected the worst however, the bottle cap did not fail us. After 5 minutes of leaving the fan on and having the turbine spin we realized that the phone was not charging. The turbine was not successfully sending an output out. We could not figure out why so we had to double check everything. We started out with the PCB board that we soldered all the electrical components on too. We double check that the negatives and positives are in the correct position and we even redid the soldered parts and clean up the back of the PCB board where all the electricity is suppose to flow. We tested with the multimeter how much volts were in the capacitor and how much it could hold. We found out the the capacitor we had on can hold 10V but, based off of the research we found online on how many volts are actually needed to charge a cell phone, We decided to change the capacitor to a lower one that way we don't ruin the phone. After making these adjustments we finally got the phone to charge. Below is a video and photo of the final deliverable.
