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!