690 likes | 814 Views
Detailed Design Review P13265 Motorcycle Safety Light Backpack System. February 15 th , 2013 RIT MSDI. MSD Team. Primary Customers: Sport bike/standard riders who ride with backpacks Surrogate Customers: Aaron League Andrew Nauss Faculty Guides: Leo Farnand Vince Burolla
E N D
Detailed Design ReviewP13265Motorcycle Safety Light Backpack System February 15th, 2013 RIT MSDI
MSD Team • Primary Customers: • Sport bike/standard riders who ride with backpacks • Surrogate Customers: • Aaron League • Andrew Nauss • Faculty Guides: • Leo Farnand • Vince Burolla • Industrial Design Consultant: • Killian Castner • Team Members: • Mike Baer, Project Manager • Tyler Davis, Lead Engineer • Ben Shelkey, ME Project Engineer • TJ Binotto, EE Project Engineer • Eric Dixon, EE Project Engineer
Today’s Agenda • Overview 5 minutes, 1 slide • Project Description Recap • Borrowed Motorcycle Specs • System Model Design 45 minutes, x slides • Family Tree, System Overview • System Components • ME- CAD Models/Drawings • EE- Schematics, Pseudo-Code • Bill of Materials • Feasibility Analysis, Prototyping, and Experimentation 30 mins, x slides • Testing for critical components • System Assembly & Test Plans 10 mins, x slides • Next Steps 15 mins, x slides • Updated Risk Assessment • MSDII Plan • Conclusion, Comments 15 mins, x slides
Project Description Review • This project is intended to be prototype stage for marketable product for motorcyclists: • Two major needs identified by motorcyclists: • 1. Safety • Hurt Report • Motorcyclist safety study performed by Henry Hurt, published in 1981 • Of the accidents analyzed, ~75% of motorcycle accidents involved collision with another vehicle • “Failure of motorists to detect and recognize motorcycles in traffic is the predominating cause of motorcycle accidents” • Motorcycle Conspicuity Study • Riders wearing any reflective or fluorescent clothing had a 37% lower risk than other riders • Conclusion: “Increasing the use of reflective or fluorescent clothing, white or light coloured helmets, and daytime headlights…could considerably reduce motorcycle crash related injury and death.” • 2. Electronics charging • Most motorcyclists have no means of charging electronics
Project Description Review • Conducted market survey regarding safety equipment and small electronics charging • Currently at 77 participants (for results visit EDGE website) • Summary of target market (motorcyclists who): • Often or always wear backpacks • Carry bulky items, such as books or laptops • Ride in 4 seasons, and wet conditions (rain, fog, snow) • Currently do not have method for charging electronics (such as cell phone) • Micro USB charging connection required • Believe visibility is important • Utilize reflective surfaces, bright colors, and lighting systems • Would consider upgrading their existing lights to LED lights • Place importance of aesthetics and durability of products
Borrowed Motorcycle • Type: 2006 Kawasaki Vulcan EN500 • Owner: Andrew Nauss, 5th year ME • Gave permission to test on bike and make small modifications, if necessary • Not ideal type of bike for target market, but it shares same engine and electronics with the Ninja 500, a popular entry-level sport bike Vulcan EN500
Physical System OverviewBackpack User Control Panel On Chest Strap Brake Lights System Power Switch AC Charging Plugin Turn Signals Electronics Box Inside Bottom Backpack Compartment
Physical System OverviewMotorcycle Wireless Light-Signals Out Transmitter Box Power Out Bike Light Signals In Bike Power In (Inside Box) Transmitter Board w/ Xbee Transmitter
Family Tree (1/3) Continued
Family Tree (2/3) From Backpack Assembly Continued
Family Tree (3/3) From Backpack Assembly
Backpack CAD Models and Drawings for the backpack are still in process and will be added once complete.
LightsSelection • Lights: • Compared thru-hole vs. flexible strips • Strips proved to be better for application • Colored LEDs documented to be more efficient than using white LED with colored lens cover • Strips available in .5m length w/ 30 LEDs/strip • Can be cut into increments of 3 LEDs • Each 3 LED segment has necessary resistors to operate @ 12V • 3 sets of High Intensity 30 LED SMD Strips • 2 amber and 1 red • $15/ strip, $45 total • *Note: 11 sections of red strips are needed, but only 10/ strip • Will instead use one amber section, but will purchase 2nd red strip in MSDII if budget allows Flexible LED Strip
LightsFlash Functionality 1st stage brake lights 2nd stage brake lights Upper Large Arrows Upper Small Arrows Dual Brightness Running/Brake Lights Lower Small Arrows
LightsRequirements Purchase: 1 RED strip 2 AMBER strips *Note: Decision made to eliminate front shoulder strap lights due to installation complexity and marginal benefit to rider (headlight is much brighter)
Light CoversSelection • Lens Covers: • Provide protection from elements • Clear thermoform acrylic sheets • Can bend to required shape • Clear: • ~92% Light Transmission @ 90 degrees incident to surface • Red and Amber: • ~9-15% Transmission @ 90 degrees • Currently in discussion with manufacturer • Will be sending free samples of both clear and red • Can hold off on purchasing until samples are received • Sheets will be cut to size and molded to sit flush with External Shell • Diffusion Material: • Diffusion material is not necessary and will not be used • Could potentially be added after completion of build Clear acrylic
USB Charger Backpack System Board Schematic Voltage Regulation Receiver Inputs and Battery Health Output to Lights Microcontroller Chest-Board
Battery SelectionTechnology • Re-evaluated initial selection of Li-Po battery due to safety concerns • For scope of project, not possible to design box that is guaranteed to prevent any damage to battery in event of crash • Li-Po and Li-Ion battery can catch on fire if cells are damaged, even with no current draw • Decided upon Ni-MH: • They do not catch fire when damaged • Still meet performance requirements • Downside, heavier and larger volume
Battery SelectionCriteria • Battery selection criteria: • Meets minimum 12V voltage requirement (from lights) • Meets minimum required power draw • Meets maximum current draw (~3.5A worst-case) • Can be connected to off-the-shelf AC smart charger • Built in overcharge protection and thermal monitoring
Battery SelectionComparison • Three options • Selection limited due to required capacity • Selection further limited due to 12V requirement • Total price includes pack, charger • Cost between 3 choices was negligible
Battery SelectionComparison • After comparing in PUGH diagram, Powerizer Flat pack/charger was chosen due to flat size and larger capacity for the same price • 4500 mAh, 12V, 4.2A max • Dimensions: 7.2 x 2.9 x .8 inches • Cost: $66, shipped • 5 day lead time before shipping
Battery Health Monitor SelectionCriteria • Battery Health Monitor Criteria: • Monitor voltage levels on NiMH Battery (14.5V-10.5V) • Be able to load shed USB charging system at a specific voltage. • Shut off system as safe shutdown (10.5V) • Send signals to Battery Status LEDs on chest strap
Battery Monitor/Charging Schematic Inputs and Battery Health
Power Supply SelectionCriteria • Power Supply selection criteria: • Low power dissipation. • Low heat dissipation. • Pass max voltage to Safety Lights • Regulate battery voltage to 5V for USB Charging System • Regulate battery voltage to 3.3V for µCon, Wireless, User Interface switches and Battery Status LEDs.
Power Supply Schematic Voltage Regulation
USB Charger SelectionCriteria • USB Charger Selection criteria: • Meet requirement of Standard USB Dedicated Charging Port • Maximize charging rate, while minimizing power/time.
USB Charger Schematic USB Charger
Light Sensor SelectionCriteria • Light Sensor selection criteria: • QSD124 NPN Silicon Phototransistor • Narrow Reception Angle of 24DEG • Power Dissipation is Max 100 mW
LED Driver SelectionCriteria • 8-Bit Parallel In/Out Darlington Source Driver • Large peak output current of 500mA • Input Voltage and Current easily supplied by microcontroller • Will drive enough current to power any combination of 3-LED segments
Wireless Transmission SelectionCriteria • Xbee 802.15.4 Low-Power module w/ PCB Antenna • Little configuration required for RF Communication • Low-Power Consumption • Low Input Voltage (3.3V) and Current (50mA) requirements • Small Physical Size • Large amount of open-source documentation
Transmitter (Tx) Board Schematic Inputs Voltage Regulation Transmitter Bike Signals
Microcontroller SelectionCriteria • Microcontroller selection criteria: • Minimize controller power consumption. • Maximize # of I/Os. • Have PWM functionality.
Microcontroller and Rx Schematic Receiver Output to Lights Microcontroller
Chest Strap System SelectionCriteria • Chest Strap criteria: • House User Interface Switches • House Battery Status LEDs • Minimize Power Consumption • Can be connected to off-the-shelf AC smart charger • Built in overcharge protection and thermal monitoring
Chest Strap User Control Panel Control Panel (Cover Off) Control Panel (w/ Cover)
Chest Strap User Control Panel Control Panel Top Control Panel Bottom
Quick-Connect Selection Criteria Must attach and detach both quickly and easily Must not shake loose Must have reasonable detaching pull force in order to prevent damage to other systems (if rider forgets to unplug) Aesthetically pleasing Low production cost
Cost analysis of Quick-Connect options Choice: Guitar Amp Connector Reasons: -Quicker to attach because of no directional preference - “Clicks” in, less likely to come off accidentally
High Cost Items Battery- $66 w/shipping Lights- $53 w/shipping Microcontroller- Xbee Units PCBs- Shell Mold Fabrication-