vgo cabinet cycle tester hanny selbak ammar al salman dragan ulemek john geile
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VGO CABINET CYCLE TESTER
HANNY SELBAK
AMMAR AL SALMAN
DRAGAN ULEMEK
JOHN GEILE
PDS
Be able to run a 25000 cycle test
Adjustable length settings for varying drawer/cabinet set-ups
Able to support a load of 15 lbs/sq ft drawer area
3-5 year life-time (depending on frequency of usage)
3 second cycle time
Smooth open and close motion
MOTION DEVICE SELECTION
The criteria for motor selection was organized as shown below. VGO currently uses a pneumatic actuator. We have chosen to go
with a
DC MOTOR.
Design Criteria Operation Cost Maintinance Life Span SimplecityDesign Idea Total
Stepper Motor 5 3 4 3 4 19Pneumatic Actuator 3 4 5 4 1 17
DC Motor 5 5 4 4 5 23
POSSIBLE DESIGNS
Need to translate rotational motion (DC Motor) to linear motion.
Left to Right: scotch yoke, rack and pinion, worm drive
LINEAR DRIVER SELECTION
Design Criteria Operation Simplicity Pitch Error Noise Effi ciency Cost Maintenance Performance Life Span FrictionCriteria Weight 0.15 0.1 0.15 0.05 0.05 0.05 0.15 0.1 0.15 0.05
Design OptionsRack and Pinion 3 5 3 5 5 5 5 4 4 5 Total
Weighted Score 0.45 0.5 0.45 0.25 0.25 0.25 0.75 0.4 0.6 0.25 4.15Worm Gear 5 4 5 5 3 4 5 5 5 4 Total
Weighted Score 0.75 0.4 0.75 0.25 0.15 0.2 0.75 0.5 0.75 0.2 4.7Scotch Yoke 2 5 3 4 3 4 3 5 2 3 Total
Weighted Score 0.3 0.5 0.45 0.2 0.15 0.2 0.45 0.5 0.3 0.15 3.2
The criteria for driver selection was organized as shown below. VGO currently uses a piston in conjunction with the pneumatic
actuator. We have chosen to go with a WORM GEAR.
WORM DRIVE SELECTION
POWER SCREW
Higher friction
Lower max speeds
Lifetime is inconsistent
BALL SCREW
Quiet motion
High speeds
Very low friction
Not self-locking
WORM GEAR WITH BALL SCREW
SYSTEM CONTROLLER
An Arduino Due was chosen to control the system. It is easily programmable, low-cost ($40-$50), and can support multiple
inputs/outputs.
32-bit, 84 MHz processor, 54 digital input/output pins
CONTROL SYSTEM
• Used a proportional controller• Feedback is from rotary encoder on worm screw
• 400 pulses per rev• Encoder senses any outside interaction• Motor voltage is varied to match desired position
DERIVED MOTION
0 1 2 340-
20-
0
20
4039.478
39.478-
x t( )
in
v t( )
in
s
a t( )
in
s2
0
30 t
Maximum displacement, velocity, acceleration, and force of the system.
Rotary motion of the worm drive with respect to the linear position of the drawer.
0 1 2 3100-
50-
0
50
10078.957
78.957-
ω t( )
rev
s
α t( )
rev
s2
0
30 t
SYSTEM PROPERTIES
1 Test = 1.8 million revolutions maximum
40 Tests/year for 5 years = 360 million revolutions
Maximum torque required to open drawer = 15 oz-in
Maximum axial force = 10 lb
The system design is meant to outlast this with minimal maintenance/replacement parts
ENGINEERING THEORETICAL DESIGN
FS MAX TOURQE 7
FS BUCKLING 32
FS FATIGUE LIFE 411
CURRENT STATUS
DESIGN COMPLETED
CONSTRUCTION COMPLETED
FINAL TESTING
FUTURE ACTIONS DELIVER TO CUSTOMER
THANK YOU!
QUESTIONS?