Group 17: Clinton Bencsik Mark Brosche Christopher Kulinka Christopher Redcay FAMU-FSU College of Engineering

Overview  Introduction  Project Scope  Prototype Design  Intended Manufacturing Process  Manufacturing Attempt #1  Manufacturing Revisions  Manufacturing Attempt #2  Planned Future work  Conclusion

 Harris Corporation $5.3 billion revenue in 2008 Fields ○ Communications and Intelligence Programs ○ Defense programs Communications and information processing products Data Links, Visualizations, and Digital Mapping Seeking a way to monitor battle field terrain ○ Monitor foot travel ○ Monitor vehicle presence

Introduction  Project Overview Design a sensor housing modeled after a maple seed for desert reconnaissance Use auto-rotating flight inherent to the design to slow terminal velocity Use infrared and vibration sensors to detect personnel or vehicle movement Send out position information Recharge batteries using solar panels located in the wing

The Design Concept Video Dramatization. Objects not to scale.

Project Scope Design a sensor vehicle to house a battlefield awareness network that can be dropped from any altitude. Project RequirementsDesign Specifications Survive a fall from a large height with sensors intact Make from a material with Young's Modulus >0.8GPa Hold a sensor array capable of detecting human and vehicle presence Design with infrared and vibration sensors to report disturbances Operate for several weeks without maintenance Use solar cells to recharge batteries or capacitors Auto-rotate during freefall similar to a maple seed Design as a scaled up maple seed with "seed" holding sensors Transmit data to a central network Design with an g transmitter to send data

Prototype Design

 Exploded View  1 - Wing 2 - Solar Panel 3 - IR Sensor (2) 4 - Vibration Sensor 5 - Micro Controller 6 - Spine 7 - Head Prototype Design Detail

Intended Manufacturing Process  The Body Using Shape Deposition Manufacturing (SDM) (1) Mill out negative side in wax mold (2) Pour in polyurethane material, vacuum out air bubbles, and allow for cure time (3) Mill out excess polyurethane to create final part  The Electronics Electronic components will be embedded in the material ○ Components will be secured using a FDM frame (1) (2) (3)

Manufacturing Attempt #1  Negative milled out of wax block using a HAAS Mill  Jagged edges are buffer area for the mill spindle so no gouging of the part was present

Manufacturing Attempt #1  Negative was filled with polyurethane material and allowed to cure  Once cured the positive side was milled  Material was not anchored, so part moved in mold during milling Positive cut did not meet original design

Manufacturing Revisions  Problems Part shifted during positive side milling which caused the mill to cut to unintended depths Spine was too flexible and broke easily Maple seed head was far too heavy Wing designed too thin for polyurethane material  Solutions Anchor points will secure part will positive side is milled Spine will have a metal rod embedded to stiffen it Holes need to be drilled and sealed with polyurethane material to reduce weight Solar panels will take place of wing material and will be secured by polyurethane

Manufacturing Attempt #2  Part remade in sections Head, spine, and wing all made separately Head had holes drilled and sealed to reduce weight Spine now includes embedded steel rod for rigidity Wing made without removing air bubbles to reduce weight

What is significant about a Maple seed?  Wing on seed is a natural mechanism for dispersing seeds over a large area.  Seeds “float” to the earth using auto-rotating flight Why a Maple seed?  Simplifies design to avoid complex moving parts  Produces a desirable spread pattern to monitor a large area

The Design Concept  Single wing auto-rotating design Seed sensor housing (1) ○ SDM manufactured ○ Integrated sensors and controllers ○ Integrated circuits ○ Integrated transmitter and power source Wing with flexible solar cells (2) ○ Provides power to battery and capacitor ○ Curve and shape cause auto-rotation in flight Wing spine (3) ○ Provides support for the light, thin wing 1 2 3

The Design Components  Sensors Infrared Sensor ○ Glolab DP-001 Vibration sensor ○ SQ-SEN-200 Omni-directional tilt and vibration sensor (a)  Power Flexible Solar cells (b) ○ Silicon Solar ○ 4.5” x 1.5” (3V at 50 mA) Battery ○ Sanyo 3V RLITH-5 Capacitor (c) ○ Panasonic 5.5V a b d c

Proposed Component Diagram  Power collected from solar cell.  Energy stored in DC battery.  Simultaneously senses infrared signals and ground vibrations.  Sensor outputs directed to microcontroller.  Signal transmitted to central unit.

Application of the Lift Equation to Auto-Rotating Wings

Simplifying the Area  Equation of area in terms of the total length of the maple seed.  Constant wing shape in order to introduce a coef. that represents that common shape.  Combining these two equations and substituting a known area, length and width:

Obtaining the Final Equation  We now combine the approximated lift equation with the simplified area to get lift as a function of length & Note: CI= lift coef., ρ= air density, ω= angular velocity

 Center of Gravity Inside head Maximizes use of entire wing length Optimization

 Use rounded edges Initial prototypes failed due to stress concentrations Optimization

Fused Deposition Modeling Prototype Overall Length – 6.75”, Seed Length – 1.5”, Wing Width – 1.75”

Final Bill of Materials & Cost Analysis  Total Cost per Seed: $92.52

Future Plan  In the next two weeks before final presentation: Final components decided upon ○ Cost analysis completed Shape prototype will be completed and tested Design ready for construction WE ARE HERE

References    

Acknowledgement  Dr. Jonathan Clark - FAMU/FSU College of Engineering Department of Mechanical Engineering ○ Use of the STRIDE Lab  Mr. Matt Christensen – Harris Corporation