For the design of my MP3 speaker I based my focus around the shape of the shinkansen train. This then tied in with my high speed rail link. I also developed my ideas around the facts about the japanese rail company as they regard themselves the safest in the world whilst also being the most reliable. With this in mind I tried to design a speaker that will be durable and reliable whilst on the go. This then gave me my target market, which was the Japanese commuter.
With my target market and the aim for my speaker set I started developing different variations of a durable speaker. I feel like I could have explored the possibilities a bit more with the positioning of the silicone and the battery compartment.
The size of the MP3 speaker was also a point I wasn't fully happy with. Due to the sleekness of the Shinkansen train I tried to replicate that in my designs. This however couldn't be fully achieved due to the constraints with the circuit components and the speaker itself. This then left my design wider then I really wanted it to. This with further work could be improved but may need either a smaller speaker or the speaker being located in another part of the shell.
The overall colour of the speaker represents the colour of the train and the colour of the company that runs trains to Tokyo.
Regarding my models I felt it was useful to make mock ups to give me an idea on the space inside the speaker. The first model helped me tweak my final measurements which in turn reduced the initial size of the speaker.
With my second model the new measurements were used and this gave me a more compact model and to fully utilise the space inside the speaker. The overall manufacturing of this model proved tricky but gave me an insight into the problems regarding manufacture when it came to my final prototype. Using this model also gave me ideas on how to hold the silicone cover in place.
Issues with the Design
- Too bulky - I believe it should be more compact if it was to be used by commuters on the trains/
- Silicone - This could be improved and utilised better as possibly a wrap around for the speaker casing to provide better protection.
- Speaker Grill - This seemed an obvious idea until manufacture came along and proved to fragile for every day to day use. This could have been picked up on in my 2nd model.
Manufacturing the speaker proved to be the most difficult task of the project. Initially it was design using the CAD software Pro/Engineer and Corel Draw. This was then put into CAM using the Laser Cutter and the Fused Deposition Modeller. This was a rather straightforward task and proved effective in producing my components. The RP machine was useful as it gave me the advantage of being a lot more precise with my measurements then I would be if constructing my parts by hand.
The problems started when putting all my components together.
There was some discrepancies with the cutting of the laser with the laser cutter. For some of my shapes it cut out perfectly but for some components it curved the line. This then proved to be a problem when lining up all the acrylic sheets ready for gluing together with the dichloromethane.
When lining up the sheets of acrylic I could possibly have used a pre made JIG that would have helped me line up all the sheets precisely. This then would have reduced the sanding I had to do to get a decent finish.
The battery holder wouldn't hold the battery without pushing up the silicone which caused problems. This was sorted by removing the holder and leaving the battery loose which wasn't what I intended on doing.
Issues with the Manufacture
- Laser cutter - I would have made replicas for my components to eradicate discrepancies although this can drive costs up.
- JIG - Create a JIG to help construct the MP3 speaker shell.
- Battery Holder - This could have been designed so that it fitted comfortably within the shell.
Using the blog has made me realise an easier way of displaying my design process and showing how I got to my final product. I believe it is an effective tool to use although I could possibly have added more sheets to the blog showing in more detail the journey I have made during this project.
Summary
Overall I believe this project has aided me in my understanding of CAD/CAM. I have used processes I was aware of before but now fully understand the constraints and limitations of the processes whilst also realising their strengths.
It has given me more confidence within CAD/CAM to enable me to teach the basics in schools.
If I had more time I would have taken more care in my final product and produced a better finish but overall I am happy with the path I've taken to the final outcome.
