Overview of Status of Analysis, Design, Fabrication, Tests, etc.
Completed static analysis test on aluminum alloy shim stock and determined k value for material
Design, fabrication, and prototype of basic housing for load cell
Presented handheld device to Dr. Hofflich
Implemented LCD screen for digital read-out with Arduino code
Researched alternative load cells
Worked with implementing 12 volts into the electric components, but found it unreasonable and very noisy
Organized the electric components to have the sensor work between 0 to ~130 grams, which was sufficient
Used potentiometers to easily change and calibrate reference voltage, yielded favorable results
Accomplishments from Previous Week
Purchased and implemented LCD screen
Solidified prototype
Built a temporary acrylic chassis
Increased Resolution to read able to read within 0.2 grams
Goals for Next Week (list names after each item). Use specific and measurable objectives.
Research accelerometers to correct orientation issues
Deciding on mechanical stopping mechanism
Decide whether or not to rework electric components to have a 12 V input or use the Arduino external power source to generate the 5 V in a made product
Purchase and implement rod system
Sponsor Comments from Last Meeting and Actions Taken to Address these Comments (indicate date of comments and if via email or in person)
Meeting with Dr. Hofflich, 4/22/2013
Liked the overall direction of the design
Was not concerned with the placement of the LCD screen, but it should be comfortable in the hand and while using with easy access to buttons
Wants us to present our developments to other doctors to get feedback
Move forward with working on a scale to determine the settings that we need to use and how numbers should print out
Gave mouth thermometer covers to use as a base for developing the disposable cover
Expressed that an aluminum/steel rod would be safe for the medical environment
was satisfied with current resolution of 0.2.
Instructor Comments from Last Meeting and Actions Taken to Address these Comments (indicate date of comments and if via email or in person)
No meeting, presentations 04/16/13
Recommended to look into other load cells, prices, and find more numbers for current system
Urged the team to buy a more sophisitcated load cell to increase resolution
Suggested using just one compliance material, such as only a spring or only shim stock
Comments from Other Students in the Class (indicate date of comments and if via email or in person)
04/16/13
Recommended moving the LCD screen to be part of the hand held device and not an extension as shown in CAD in presentation
Making the rod itself disposable
Suggested making the compliance material only shim stock
Gave website for inexpensive accelerometer
Risks and Areas of Concern
LCD screen
Correctly coding the system to include the LCD screen
The LCD screen creates a lot noise in the system
Material of shim stock
several different kinds of material to pick from: brass, copper, and magnesium
New load cell
correctly configuring the new load cell give ideal resolution and accurate results
Deformation of the shim stock
finding the right mechanical stopper to prevent elastic deformation of the shim stock resulting in skewed measurements
Resources or Information Required but not Available
Further instruction on how to implement the LCD screen into the system
Schedule
Mechanical Prototype Device with new shim stock week 5
Electrical Functioning Design Prototype with LCD screen week 6
Test new load cell
Fully Functioning Prototype with mechanical and electrical components functioning week 7
Optimizing Final Design week 7-9
Finalized Prototype wee k 9-10
Items to buy:
Mystery metal
5V Arduino Power Cord
Futek Load Cell Model LBB200
Aluminum Rods
Current Purchases:
LCD Screen: ~$25
Budget remaining: 1389.00
Progress on Report and Webpage
Began developing front page
Completed Background
Worked on Existing Solutions
Completed Statement of Requirements
Worked on Impact on Society