Week 12 Team Update

This week, the team accomplished a lot in terms of productivity towards manufacturing. The team was able to finish machining several components in the student machine shop, and also able to test the functionality of the device. This was done by hooking the Pololu DC motor up to an oscilloscope to see if it produced enough voltage to feasibly charge a phone It was confirmed from testing that the motor could output much more than the needed voltage. Because many of the orders took several weeks to arrive, it was a slight rush to get the components to arrive on schedule and Also accomplished was the final submission of the case design to the 3D printer, which is on schedule to be completed before the Design Expo. The team is on task with the high probability of completing the project before the expo and having a working demo at the booth. Still to be done is make sure that the harnessed energy can actually charge an iPhone with a working charging circuit, and integrate all components (including circuit board and mount plate) into the 3D printed case.

week 12 -Eciting Findings

Although a stressful realization, it was still interesting to learn that to charge an iPhone, providing the right current and voltage is not really enough. A special circuit must be made so the iPhone realizes and accepts a charger.
Another exciting finding was that we were able to makes some of our parts even smaller, while machining them and still maintain our stress tolerances. More specifically, we were able to make the part that hols our clutch spring a little bit smaller, saving space, weight, and reducing the materials used!

Week 12-Challanges

Our biggest challenge now is to ensure that our device, the "Clutch" is assembled, tested, and ready to go in time for the design expo. Currently all of our parts are in, and most of the "Clutch" is assembled. However, it is still not 100% completed, and we also still have to get our 3D printed housing, and then lay carbon fiber over it. We also will have to test it and ensure that the iPhone accepts it as a charger, via circuits, and ensure that it successfully charges the iPhone.

Week 11 - Status

Design expo is scarily close, and while we are on track to finish I am still nervous about the timing. We still need to machine a few simple parts and are still waiting for our clutch bearing to come in. If that bearing isn't here on Monday we might be in trouble. However, the majority of the work left for the prototype is assembly, and we are signed up for machines on Monday and Tuesday. We also have all of the components we need for the circuit board except for the iPhone cable. I don't know if there is going to be a more complicated wiring system to connect the charging cable, but I intend to put together the rest of the circuit tomorrow.  The CAD of the case shell has been submitted to 3D print just a little while ago, and we were told that it should be done by the end of the week. Brian is working on the poster, and David has volunteered to handle our business plans. It seems that everything is on track to finish, but nothing has come together yet. Hopefully in a few days we will have a poster, a working prototype and a partial business plan for the final report!

Week 11 - What's Next

We are so close to design expo!!! We have all but one of our parts in, and this next week we need to assemble and test our prototype. I am concerned that we won't have very much time to fix things if they don't work on the first try, but Dr Luntz (who I spoke to on Friday) seems to think that our testing will run smoothly and that replacing parts should be easy if something breaks. We also need to get our poster together and printed. We seem to be right on track, but time is very tight.

Week 11: Exciting Findings

The biggest development this week was finding out just how small some of our parts were. It was a definite concern for us that, if the parts we ordered turned out to not really work with the dimensions we needed, we would have to reorder and wait for everything to show up again. However, we were pleasantly surprised by the size of the motors, but even more so by the Zener diodes, which were much smaller than we anticipated. This helps us because with our size restrictions limited to the size of a standard phone case without becoming cumbersome, the smaller the parts, the better. The challenge of it is being able to assemble it all without breaking anything.

Week 11-Challanges

Rolling through week 11, our biggest challenge is now assembling and testing our product in time for the deign expo! As we begin this process we are finding that assembling our spring system, designed to ensure that after the user pulls on our string connected  to the motor shaft, the string is retracted back in to the case. However, this is proving to be harder than anticipated due to space, time and the type of springs we can use in our system. Another challenge is going to be to test our electronics. Due to our teams lack of experience in circuits this may prove to be more time consuming and harder than we anticipated. We are still optimistic, and hope that this will not take too much time. Nonetheless, ensuring that we obtain he most efficient system, mechanically and electronically is not going to be easy!

Week 10 -What's Next

The next week will be used to manufacture and assemble the components of our device. The machine shop will be used to mill the base plate, pillow blocks and motor mounts. The electronic circuit that will be used in the device must also be configured. Then the transmission, motor and electronics can all be assembled after all the necessary components arrive. Hopefully there will be time this week to also test each part of the device to ensure it functions properly. While this is being done a member of our group will also be working on the business plan and financial analysis before completing the conjoint analysis.

Week 10 Exciting Findings!

As we prepared for GR3, and surveyed which colors people liked and found reliable or fun, we found that mot people found black to be the most reliable. We also found that engineers found the carbon fiber print to be the most reliable. Nonetheless, it was interesting to see a correlation between the color and reliability, instead of material and reliability.
Another interesting finding was how well we anticipated our needed space inside the phone case! While designing the CAD it was nice to see that we did not need to redesign to many things in order to accommodate  all the internal components.

Week 10: Project Status Update

The team has passed Gate Review 3 and is now ready to begin construction. A design for the case shell has been designed and CAD, and further manufacturing process development is underway. It was decided that the best option for manufacturing the case will be a rapid-prototyped ABS part via 3D printing, and then capped with carbon fiber for rigidity. Because the device will see up to 25 lbs of force distributed over where the motor is mounted, basic FEA analysis has been done on the case shell to ensure it will not suffer from fracture or yield during normal use. The carbon fiber cap also makes sure of this. 

Part orders have been placed from Mouser Electronics, Pololu, and McMaster. Upon arrival of these components, the team can get in the machine shop and begin manufacturing the parts needed to conduct testing on the motor setup. Manufacturing plans and diagrams have been developed for quick manufacturing in the ME student shop, which will decrease time required in the shop. The team also scoured for materials that can be used to build the case this week in and around the ME X50 assembly room area. 

Currently being worked on is cost analysis,conjoint analysis to choose the best consumer preferences for the device, and the business plan.

Week 10 - Challenges

Now that we have been approved to order parts and begin building, it looks like the biggest challenge that we face is the time constraint. There are a few bugs in our design that can only be worked out by testing, and hopefully everything can be solved in the next few weeks. I'm sure that we could make our design better if we had another semester instead of only a month, but we have to get enough done to be satisfied with our working prototype. We will have to create a schedule and stick to it and should divide up the work into sub-systems that can be verified independently. Another challenge relating to time constraints is shipping times. While shipping is relatively fast when parts are made in the US, shipping from Asia takes 1-2 weeks. If something breaks at the last minute, it will be impossible to reorder parts from overseas, and we may have to pay very high overnight shipping fees even if the parts come form within the US. It will be better to begin building early so that we have enough time to make mistakes and don't run into these problems.

Week 9 - Project Status

This weekend we are working hard to complete Gate Review 3. As of this writing, the pieces are coming together nicely, and I expect to be able to submit the report to Professor Brei by the end of the day tomorrow. Gate Review 3 is quite involved though, and it has taken a lot of diligence to move it forward so quickly. While we were given plenty of time to complete it, we got very stuck on motor selection and were unable to move forward until the end of last week. After extensive office hours with Dr Luntz, we were finally able to choose a motor and find suitable transmission parts to begin the CAD. A detailed analysis of the motor and transmission have now been done for the Gate Review, and Nick has been hard at work on the CAD model. We were pleasantly surprised that one of the most readily available motors happens to produce exactly the power that we need and is very compact (only 0.4" in height)! It also turned out that the clutch bearing that we were looking at can provide the remaining gear ratio that we needed on top of the motor, and that we won't need to add any extra transmission components. This greatly reduces the size of the device.

So far, everything looks pretty good. Realistically however, I know that not everything that we have planned will work the first time, and that we will probably have to make changes to the design. I am anxious to order parts and start building so that we can begin to work out the bugs!

Week 9: What's Next

As we move on through Gate Review 3, our next step is to develop and complete a business plan, approaching the Design Expo. We have complete material research and component research, as well as a final design, so our next task involves figuring out manufacturing costs and production costs for the product. In order to develop a coherent business plan, we are also looking into different production methods so that we are pursuing the most efficient and cost-friendly method of production. We have to consider the other aesthetics involved in the design that are geared more towards production, such as color. These have been resolved using the Kansei method of selection, and will be taken into consideration as part of the business model.

Week 9 - Exciting Findings

While deciding ways to transfer the power generated from the DC motor to the actual Iphone, we were continually bouncing back and forth between using a battery or a set of capacitors. We ended up finding that we could actually use two super capacitors instead of two heavy batteries, to collect and dissipate charge between the DC-motor and the Iphone. We also found that this saved space and weight, which was extremely important as continue to determine the best way to manufacture a housing that will also serve as a case for the Iphone. We also found that due to the size of the one direction ball bearing we will be using with our DC motor, on its  shaft, we may not need to have a gear train to increase the gear ratio. This again, saves space, weight, and more importantly, reduces chances for losses in efficiency!

Week 9: Challanges

As we are preparing for gateway review 3, we are finding that our next biggest challenge will be fitting all of our components needed for completing our circuit and generator, all inside our iPhone case. We are also a little concerned with how we will make the plastic component of our iPhone case that will also hold all of the components. If we decide to use injection molding, manufacturing the mold case will be be both difficult and expensive. we will have to make the mold out of a single piece of aluminum and this could also result in insufficient tolerances and precision. Our other option is to 3-D print the part. However, this could result in an unreliable and imprecise case. Nonetheless, manufacturing our housing, and ensuring that all of our components fit inside of it, will be a big challenge, but critical to the success of our project. 

Week 8 - Our Project Status

In the last week we have looked further into our design specifications. We calculated the power that the motor must be rated for and did an extensive search for motors that fit this requirement and were small enough to fit into our design. We then found the specific parameters of the motor by looking up information on the data sheet of each potential motor. This allowed us to start modeling the system and to figure out the optimal motor for use in our application. We then looked into potential gearing as well as a clutch system that would work with these motors. The information gathered will be related to what must be done for the gate review. Other aspects of the gate review were also considered when choosing the design. However, more work must be done in the following week to complete the necessary tasks for the design and review.

Week 8 - Exciting Findings

This week we are excited to solidify the design for our product. Gate review 3 is just around the corner, and we need to select a motor and transmission so that we can move forward. This is the part of the design process that everyone has been looking forward to as engineers, and hopefully we will be able put this enthusiasm to good use.
Last week, we got some good input from Dr Luntz about modeling our power system, and our preliminary findings show we will definitely be able to find a motor that fits our needs. While we are still looking to reduce size and weight, there is a motor available that is only 10mm in thickness and can handle twice the power that we need. We are still looking for other smaller versions, but this first one would be suitable and can make our design possible.

Week 8: Challenges

Our biggest challenge right now is finding a motor that will be able to take our input torque and convert it to the necessary output voltage, while maintaining the smallest size possible. Using our known input and needed output combined with dc motor performance calculations, we plan to test different motors and their motor constants to determine which mote will be the best for our application. We also are working on the best way to position a clutch mechanism with the dc motor to ensure the transfer of a continuously inputted force is converted to electrical energy in the most efficient manner possible. In addition, we are determining what kind of materials to use in our case, as it has to be able to hold all of our components under the high torque inputed by the potential user.

Week 8 - Whats next

Our next step is to determine what kind of motor to use as well as what qualities the motor needs to have. While we know what our input torque will be and what our output voltage needs to be, we need to find a motor that can take the input toque and convert it into the needed output voltage, while still being small enough to fit within our desired dimensions. We also need to begin constructing a 3-d CAD model of our design, and considering what materials we will use in our design.