Athletic Field Marking Device Anthony Cortese, Ryan Crump, Matthew Lawler, Patrick Shaughnessy (Team Leader), John Sudia

Project Objective To create a semi-automatic device that provides a means of lining an athletic field.

Solution Requirements Must accurately paint a straight line between two determined points Must have the capability to make error corrections on its own. Must operate with as little human interaction as possible

System Goals The device should be able to complete a line 120 yards long The device should require less long term costs than current methods The device should require less human labor than current methods The device should complete its tasks in a reasonable amount of time

Major Challenges Dealing with the accuracy of all of the components in our machine Creating a drive system that can correct itself when deviating from the desired path Keeping the expense of the product to a minimum Working in a multi-disciplinary team atmosphere

Current Spraying Devices Wide BoomSmall Boom

Components of Design Solution Guidance System Drive System Paint Delivery System

Potential Guidance Solutions Differential RTK GPS High accuracy GPS, ranging from 10cm to 1cm High cost and complex implementation Laser Optical Guidance Utilizes laser scanners which give out X and Y coordinates and heading High accuracy but cost prohibitive Infrared Sensor Reflective infrared sensor Cheap and easy to implement

Potential Drive System Solutions Gas Powered Engine Heavy vibration Weight issues Complex integration Electric Motor Cheap and readily available Easy to control Simple integration

Potential Paint Delivery Solutions Compressed Tank A compressed tank Paint modulation control Spray nozzle Complex and expensive Aerosol Spray Can Inverted spray can Solenoid to trigger it Simple and low cost

Guidance System Solution Ryan Crump

Schedule

Guidance System Solution An infrared sensor retrieves location data Microcontroller receives and processes data from sensor Motor controller receives instructions from the microcontroller and outputs voltage to motors

Guidance: Infrared Sensor The Lynxmotion board consists of three reflective infrared sensors Our system uses the outermost sensors to determine its location relative to the target line These sensors each relay either a ‘0’ or ‘1’ for absence or presence of a line

Guidance: The Handy Cricket The Handy Cricket microcontroller processes the digital output received from the sensor Based on input, the microcontroller determines device location relative to line The microcontroller determines appropriate correction necessary and transmits data to motor controllers

Code Block Diagram Left sens = 0 Start Input left sensor Input right sensor Right sens = 0 Stop Input right sensor Right sens = 0 No change Increase right Motor speed Increase left Motor speed Y Y Y N N N

Guidance: Motor Controller The motor controller can precisely control the speed and acceleration of the motors for easy path correction

Electrical Schematic V Solenoid V IR Sensor M MC + - Microcontroller M MC V Digital I/O 5V Signal + - Signal IR Sensor Serial bus Sensor input 5V Relay

Drive & Paint System Solutions Patrick Shaughnessy

Drive System Solution

Each side is independently powered by a separate DC motor That DC motor drives a sprocket connected to its side’s drive train That drive train is responsible for transferring power to both wheels

Drive System: Motors The motors are ¼ HP, 180 RPM and require a 12 volt/3 amp power supply Max torque and lower speeds needed for our application 2:1 gear ratio was selected to give more torque and a lower speed

Drive System: Gear Ratio To achieve our gear ratio, the motor turns a 12 tooth sprocket which is attached by a chain to a 24 tooth sprocket on the rear axle

Drive System: Drive Train The rear axle has an additional sprocket which connects to another sprocket on the front axle in a 1:1 ratio by a chain Each axle is supported by two ball bearing mounts attached to the frame The 8” diameter wheels are locked onto the axles by a custom wheel mount

Drive System: Drive Train

Paint Delivery Solution The paint delivery system consists of a linear pull solenoid, trigger and spray paint can The solenoid will pull a trigger which will dispense paint from the can When it is necessary to halt painting the solenoid will release the trigger ceasing the paint flow Width of line is adjustable

Paint Delivery System Pictures

Cost Analysis The Handy Cricket: $99.00;Prof. Dougherty Lynxmotion Sensor: $32.00 Gamoto Motor Controller: $99.00 x2 = $ Solenoid:$10.00 Wheels:$8.69 x4 = $34.76 Bearings:$4.64 x8 = $37.12 Sprockets:$22.33 Chains:$21.94;Battlebot Aluminum Frame:$114.00;Projects Room Motors:$85.00 x2 = $170.00;Battlebot Miscellaneous:$ TOTAL:$ Existing Methods:>$

Conclusion While we have not yet completed our project, we have learned some important lessons We still view our initial goals as attainable and anticipate reaching them upon conclusion

Concluding Video

Questions?