Aluminum Smelter Inspection Robot Joe Foley, Instructor RU Hönnun-X Vorið 2011

The Customer Currently: An inspector with a thermal camera on a cart walks down the inspection route under the smelter pots He checks the video looking for hotspots Aluminum Plant at Straumsvík

Inspection Corridor Big corridor so maintenance vehicle can fit Open to outside = cold Lots of vehicles Corridor, column 3

The Team B.Sc. Students at Háskólann í Reykjavík Instructors: Dr. Jón Guðnason and Dr. Joseph Foley

Structure of Work 12 week period – SCRUM – Teams Mechanical Electrical Sensors Software 3 week intensive – Integration, testing Design review at SCRUM

Robot Frame

Structural materials Stainless AISI 304. – A bit heavy but easily available

Structural Analysis ANSYS Simulation

Transmission Timing Belts Ratio of 1:9

Wheels Independent two drive wheels with front caster Hubs custom machined(AISI 6060). Front wheel stock

Timing Belts Transmission to wheel belt Motor to Transmission

Outer Shell Stainless Steel AISI 304. Bent, welded, screwed together. Edges further sealed with RTV rubber Sized for 6 batteries.

Electrical Passthrough Partition for electrical isolation and environmental Easy to access motors and batteries without disturbing electronics Edges and passthroughs sealed Partition on hinge

Top Stainless Steel AISI 304 Top angle for mounting the RFID antenna Nice ergonomics for switches

Power Source Motor power: 2 12V Golf-cart batteries In series to make 24 Volts Peak 50 Amps Electronics power: 12V small battery Everything else 12 Volt Motor batteries 12 Volt Electronics batteries

Motors 2 24 V, 120W DC motor from scooters rpm through the 1:9 transmission

Motor and Battery Compartment

Motor Controllers Pololu 24v12. – One per motor RoboClaw – Originally for both motors, but repurposed for analyzing the tachometers – Sent to FitPC controller via serial Polulu 24v12 RoboClaw

Spennudreifing 24V power – Relays for emergency stop and general safety 12V power – Three relays – Eight sensors – FitPC computer – Arduino microcontroller – Audio amplifier – LED lighting 24V Safety cutoff 12V distribution

Arduino Mega Sensor processing is done through the Arduino Mega Motor commands are sent directly to the controller The Arduino Mega has a ATMega2560 processor which has – 56 digital IO pins – 13 analog inputs – USB – 4 serial ports Arduino Mega Shield for Mega

Audio Amplifier Audio feedback and warnings allow the robot to indicate status and get attention 10W Amplifier

Complete Electronics

Electrical Block Diagram

Fit PC 1,6 GHz processor 1 GB memory Size: 100x115x26mm 60GB Solid State disk

Operating System Ubuntu server. Non-GUI Linux. ROS (Robotic Operating System).

Documentation

Thermal Camera FLIR E4: Currently used Max 900°C. Stores in JPEG

Image to Temperature Python og OpenCV in Linux Individual pixel processing – 255 (= white) is max temperature – 0 (= black) is minimum temparture Adjust our threshold according to the range – Example: Range set to 100°C upp í 350°C – Value of 100: 100*(250°/255)+100° = 198 °C Greyscale raw image

Data processing If above our threshold (300C) then store image Temperature statistics in Sqlite database: Average Standard deviation Maximum Current position (ROS) False color highlighting threshold as green

RFID Location found using RFID Reader: TagSense Micro UHF ( MHz) 3,8cm * 4,6cm * 0,7cm USB interface Voltage: 5V Current: 250 mA Antenna: Frequencies: 865 – 956 MHz Gain: 6 dBi SMA connector (inverted) Reads tags up to 80 cm Micro UHF reader Antenna

RFID Merkin: ShortDipole Impinj Monza 4 from UPM. Frequency: MHz Size: 93mm*11mm 96 Bits of information – Aluminum pot, column, etc. RFID tag

RFID Location Map of corridor One tag per pot Each number is associated with information in the SQLite database Database instructs possible future actions for robot

User Interface User can track current location of the car remotely Queries the SQLite database to track and find out status

Position control (e. Localization) Encoder: pulses per rotation. Wheel radius R = 13,54cm Circumference = = 85,07cm Resolution= Encoder

Ultra Sonic sensor

IR-Sensor

Turning (IR - feedback) l = distance between sensors d = delta of sensor readings d = sk1 – sk2

PID - loop

Complete!