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?