1. UMBREMECH
SENIOR DESIGN PROJECT
By Josue Figueroa

2. Agenda
 Introduction
 Purpose
 Objectives
 Specifications
 Final Product
 Parts Fabricated
 Control System
 Parts
 Features
 Functionality
 Battery Facts
 Flow Diagram of Code
 Future Considerations
 Conclusion

3. Purpose
Design a mechanism to electrically operate an
umbrella which allows a wheelchair-bound
individual w/ limited mobility to shield
themselves from precipitation and direct
sunlight, w/out the need of physical strength
and/or assistance from others.

4. Solution – UmbreMech!

5. Objectives
 Provide full coverage for the wheelchair
occupant
 Allow clearance between the occupant and
the umbrella while deployed
 Design an easy-to-use user interface to
control the umbrella
 Intended for electric wheelchair use.

6. Specifications
 Attachable/Detachable
 Shade < 40 in. diameter, Case < 12 in.
diameter
 12 VDC/2.5 Amps
 Product ~ 30 lbs
 Height of arm < 2 ft
 Corrosion resistant material
 Deployment/Retraction time < 20 seconds

7. Final Product – Exploded View

8. Parts – Fabricated
Rapid Prototyped Turntables Flanges
Gears
Motor Mount/Gear Mounting/
Umbrella Support Motor Mounts & Pulley Turntable Supports

9. Parts - Control System
Arduino Mega 2560 3 x SideStep Chopper Motor Drivers Battery 12 VDC 9Ah
http://arduino.cc/en/uploads/Main/ArduinoMega2560_r2_front.j http://www.probotix.com/image/SideStep.jpg http://ecx.images-
pg amazon.com/images/I/4143kOFXJpL._SL500_AA300_.j
pg
2 x Nema 17 Planetary
Nema 17 Stepper Motor Misc Parts
Gearbox
Stepper Motors
http://www.phidgets.com/images/3312_Big.jpg http://www.phidgets.com/images/3303_0_Web.jpg

10. Parts – Control System (Cont.d)

11. Features - Control System
 Rotation – 360
 Tilt - 45 in either direction
 Flip Up/Down
 Power Saving Modes – Using a counter
 Save motor power when idle or in the starting position
 Location Maintained in Memory - EEPROM
 Fail-Safe with Power Loss

12. Functionality – Block Diagram
Orange Arrows = Power Connections
Blue Arrows = Input/Output

13. Battery Facts
 Current setup uses 12V 9Ah Sealed Lead Acid
Rechargeable Battery (Inexpensive for demonstration
purposes)
 Typical electric wheelchair battery is 24V
600Ah
 Design is adaptable.
 Motor drivers can handle 24V input
 Voltage Regulator (LM317) needed for Arduino -
24V to 12V decrease.

14. Flow Diagram of Source Code
Legend
Conditional
Statement
(Is Button Pushed?)
Rotate Corresponding
Motor in Certain
Direction

15. Future Considerations
 Further Constraints
 Reduction of Cost and Weight
 Further Safety
 Design Flexibility
 Profitability of Design
 Incorporate Sun Sensor
 Smartphone Application

16. Conclusion
As the handicap population
grows, technological innovations such as
the UmbreMech will service the growing
need for automated systems on
wheelchairs.

17. Questions?

18. Analysis for Pulley System
Pulley 1 Body A Body B Body C
.C
B . .C . . .
k
Assume zero friction:
. A
Pulley 2 .
z The circumference of Pulley 2 = z