Overview of Status of Analysis, Design, Fabrication, Tests, etc.
Final design decision: timing belt drive
Preliminary analysis of stepper motor requirements
Analysis of pulley pitch diameter with respect to desired positioning accuracy
Design choices on continuous support linear shaft, ball-type linear pillow block bearings, timing pulley
Linear shaft potential materials: (ceramic-coated) aluminum
Pillow block material: aluminum
Timing pulley material: polycarbonate, aluminum bore
Source: PBC Linear, Stock Drive Products
Accomplishments from Previous Week
Individual component analysis for Encoders, Stepper Motors, Drive System and Data Acquisition completed
Transported mock bore to lab space
Created SolidWorks CAD model of potential belt design
Goals for Next Week (list names after each item). Use specific and measurable objectives.
Confirm if sponsor has LabView (Brian, 4/17)
Determine if the stepper motor can be left on during scan (to hold position) (Ola, 4/17)
Clarify sponsor's preferred method of controlling the device (Alex, 4/17)
Comparison and product search for belt drive components (Sally, 4/17)
Purchase and begin fiber optics testing (4/11)
Sponsor Comments from Last Meeting and Actions Taken to Address these Comments (indicate date of comments and if via email or in person)
Maximum sample mass = 0.7 kg (4/4)
Diameter = 72 mm
Length = 170 mm
Shape = Cylinder
Density of Water = 1000 kg/m^3
Note: additional mass from testing/monitoring equipment
Goal is to design and build a base, moving platform with a generic template of screw holes, do not need to worry about cantilever part (4/4)
prefer to use brass screw/bolts over 316 stainless steel screws/bolts
maximum mounting plate size: 2 ft x 8 in
Instructor Comments from Last Meeting and Actions Taken to Address these Comments (indicate date of comments and if via email or in person)
Compare pros and cons of concepts: lead screw, belt drive, cable drive (4/3)
include lead time, cost, availability, part #
Design resources: Stock Drive timing belts (4/3)
if a good belt resource is found, send information to Pedro
Look up cable drives (4/3)
[Stepper motors] need lots of torque to prevent loss of steps (4/3)
Try to buy a lead screw instead of fabricating one (4/3)
Find stepper motor for worst case scenario (4/3)
high factor of safety doesn't hurt
Comments from Other Students in the Class (indicate date of comments and if via email or in person)
N/A
Risks and Areas of Concern
Efficiency of belt drive with horizontal versus vertical positioning
Minimizing distance between support bearings on mounting plate
cantilever torque effects on belt and bearings
Load capacity of timing belt
Implementation of belt tensioner
Resources or Information Required but not Available
None at the moment
Schedule
Finalize design concept
Update Gantt chart.
Budget (list amount spent and amount remaining)
Spent: $0
Remaining: $1500
Progress on Report and Webpage
No changes to report, webpage has been updated to current week