2. Special Thanks to:
◦ Professor Charles Dimarzio for his assistance in the
optics analysis and use of his lab
◦ Colin Fredette for his assistance with specifications
and obtaining machine parts and components
3. Can probably
modify this
section to
some degree
Datum Can’t modify
this wall
Location of
current slit
holder
Bottom
clearance taken
from this
surface
4. Focus on repeatability between different
positions
◦ ±25µm in the sensitive direction
◦ ±150µm in the less sensitive direction
Straightness of travel: < 10µm
8. Top view of the semi-hexagonal assembly, showing
the entering light beam passing through the aperture
slit and being refined.
Also displays how the assembly is rotated to adjust
between the three different slit options.
9. Lab setup for testing
Light Source
and Holder
Light Focusing Aperture
20x Magnification Lens
Light Detecting Camera
Aperture Slit
13. USB B to A
Bi-polar
stepper motor
Arduino Uno
ATMEGA328
Controller
14. Specifications
Cost: $142.50
Error: Less than 0.001 degrees
Operating Life: A minimum of 2000 hours
Hardware Control: Arduino Uno ATMEGA328
Software Control: MATLAB
15. MATLAB GUI
Designed for simplicity
3 state architecture with power down command
16. Control System Cost
◦ $142.50
Overhead Holder Cost
◦ $1,102
Total Cost
◦ $1,342.33
Mass Production Estimated Cost
◦ $400.88
Percent Increase on Optical Detector Cost
◦ 10%
17. Broken Down to 5 Phases
◦ Design – Completed on 10/1/2012
◦ Modeling – Completed on 10/25/2012
◦ Ordering – Completed on 11/16/2012
◦ Construction – Completed on 11/30/2012
◦ Final Assembly – Completed on 12/2/2012
18.
19. 25µm constraint is due to the size of the PDA
pixel
Resolution depends on width of the slit
Current resolution with 50µm width slit is
5nm
20. Image of a 50µm slit
Image of a 100µm slit
Editor's Notes
Aaron: introduces the project, and everyone’s names.
(15 seconds)
Aaron: Overview Project Goals/Problem Statement/ Need for the Project – (Update the slide according to what poster says)
(1 minute)
Aaron: Overview of the path of the solvent, through to the optical detector, talking breakdown, quick overview of HPLC.
(30 seconds)
Aaron: Overview of how the light travels through the system position need for the slit in reference to the photodiode array.
(30 seconds)
Paul: Details about casting, highlight minimal alterations to the system (noting areas where modifications can/can’t be made), position of previous and new slit holder, note that the references are based off this datum for the positioning of the system.
(1 minute)
Paul: Detail the dimensions are based off previous datum, state that we couldn’t have an additional reflection in the system.
(15 seconds)
Paul: Mention the 3 sketches, and detail the cons of the size constraints and fit-up, as well as the lack of interchangeability or modularity for customer customization. Pursued rotational design, but too much stress in joints to properly machine.
(1 minute)
Paul: Briefly mention features of the system, interchangeability of slits, slot easy machine holder and base, rotational dimensions, mention that it is black anodized aluminum to eliminate the reflection from the aluminum. The attached aperture slits are made from molybdenum for lack of reflective properties, smaller slits to fit the system.
(1 minute)
Paul: The overall system stacked onto the motor and gearbox system with a 26.85 actual gear ratio, correlating to a 0.067⁰ step
(15 seconds)
Paul: Show how the light travels the rotational system, and that the system travels between the 3 set points. Note that the exiting beam is refined.
(30 seconds)
Hanshen: Explain the axis of the system, explain the straight line of the system, and simplifying the light path, eliminates the reflection of the mirrors. Mentions the 27% intensity drop, or the shift of 25µm max.
(1 minute)
Hanshen: Slit magnified 20x, measure coordinates of each edge, as well as the intensity of the image as a BMP.
(30 seconds)
Hanshen: Comparison image, notice the similarities showing the repeatability in the system.
(15 seconds)
Hanshen: Number of tests performed, noting the Min, Max, Average, and Standard Deviation of the system, noting all values are less than the 27%.
To create the rotation, Kevin will explain the control system
(30 seconds)
Kevin: This is the hardware used. The H-bridge circuit allows the transition between directions. The motor system is a small NEMA 11 configuration, overview of the system in general, and that the device sits on the motor shaft.
(45 seconds)
Kevin: Specifications on the system with an expected error of backlash of 0.15 for each step which is assumed in the gearing calculations. A cost of $142.50 with an Arduino hardware interfaced with a MATLAB software system, powered through the computer USB connection. Minimum operating life of 2000 hours.
(45 seconds)
Kevin: Explains a simple GUI (or command window) to integrate the user requests with the system. Mention that it makes 895 geared steps. If the system needed calibration, the number of steps could adjusted in the interface.
(45 seconds)
Aaron: Estimate of materials labor etc., and then the cost could be reduced for mass production by buying in larger quantities. System will create an overall price increase of XXX.
(30 seconds)
Aaron: How we broke down the project into phases, dates completed, etc.
(30 seconds)
