Team 1617: Autonomous Firefighting Robot Katherine Drogalis, Electrical Engineering Zachariah Sutton, Electrical Engineering Chutian Zhang, Engineering Physics Advisor: Professor John Ayers

Overview Project Goals & Contest Background Mechanical Design Navigation o Localization o Kinematics o Software Flame Search and Extinguish o Mechanical o Software Sound Activated Start

Autonomous Firefighting Robot: Goals ✓ User initiated, autonomous start & navigation ✓ Search for and extinguish burning candle ✓ Extendable to real life situations ✓ Trinity International Robot Contest (April 2-3, 2016) o IEEE Award: Outstanding Robots from Connecticut

Trinity International Robot Contest 8x8’ plywood maze Timed trials Unique robot 31x31x27 cm robot Test ArenaArena Layout

Mechanical Parts / Structure Navigation o 360 o Laser Scanner Extinguishing o 16*4 Thermal Array Sensor o Compressed CO 2 Computing o Raspberry Pi – navigation o Arduino Mega – actuation & flame extinguish Motion o DC motors with encoders Power o 16 V, 5500 mA/h rechargeable battery

Considered: SLAM (Simultaneous Localization and Mapping) o Requires a lot of processing (slow) Speed / simplicity is important Now: Monte Carlo Localization with Grid Map o Start with uniformly distributed “samples” or guesses of robot’s pose o Apply motion to all samples o Compare laser scan observation to sample observations o Weight samples based on similarity to laser observation grid map o Resample from newly weighted sample distribution Navigation

Global MapMCL Simulation Source: Navigation

Runs on Raspberry Pi Series of open source Python/C++ scripts that work together seamlessly Performs scheduling/parameter settings for various “nodes” or scripts Downloaded packages for navigation (“Navigation Stack”) o Localization o Laser scan processing o Global path-planning (get to goals) o Local path-planning (obstacle avoidance) o Calculate velocity commands o Communicate with Arduino ROS (Robot Operating System)

ROS Block Diagram

System Block Diagram

Flame Searching (Mechanical) Processing done on Arduino RoBoard 16×4 Thermal Array Sensor o Produces a map of heat values o 1.5m range o Field of Vision: 60º horizontal, 16.4º vertical Scan 360 o o If candle is detected, pivot to center on flame o If centered, move forward to candle o If no flame, Raspberry Pi takes over Total Field of View Thermal Array Sensor

Flame Extinguishing (Mechanical) Compressed gas (CO 2 ) o Best option for large-scale fire – bonus points! o Portable bicycle tire inflator o Replaceable 16g CO 2 cartridge o Extended nozzle at the front aligned with the sensor Release o Servomotor initializes to push the tire inflator button During this whole process: o Pi functionality and thermal camera are always running o Velocity commands from the Pi are ignored

“Candle Scan” o Creates array of all pixels over 60 o C and their locations o Sets “Candle Detect” flag – initializes LED “Flame Align” o Prompted by “Candle Detect” flag o Determines which pixel is the hottest o Calculates how far the robot needs to pivot in order to center on that pixel “Extinguish” o Initializes the servomotor when CandleDetect == 1, MaxValue > 280 o, and -1 < ColumnTurn < 1 Flame Extinguishing (Software)

Miscellaneous Features (“Start Board”) Sound activated start (microphone) o Buzzer frequency: 3.8 kHz ±16% o Tried: Bandpass filter – bandwidth too large o Decided: Frequency to voltage converter circuit Kill power plug Flame detect LED

Questions?