Power Bot Group 2 Luke Cremerius Jerald Slatko Marcel Michael TarikAit El Fkih Sponsored By: Aeronix Inc.
Project Description • Autonomous Robot with onboard auxiliary battery • Used to provide supplemental power to mobile devices (laptops, mobile phones…etc) • Uses onboard navigation algorithms to navigate to users location • Has iOS application to provide robot statistics and is used to control PowerBot’s movements.
Project Motivation • Battery life longevity in mobile devices is a constant issue. • Wanted to create a charging solution that could charge the device without inconveniencing the user. • The device would be simple to use, allowing for easy adoption into a users everyday routine.
Objectives • PowerBot will be able to navigate autonomously to a users location. • PowerBot can be remotely controlled by user input, through the use of an onboard camera and the provided iOS application. • PowerBot will contain a battery used to charge external devices through the use of USB, DC, and inductive charging.
Specs • Will be at most 36” long • Max speed of 5 mph • Battery life of minimum 24 hours • Able to charge mobile phone from 0% - 100% without needing to recharge internal batteries • Will re-charge internal batteries through in-home AC and/or via onboard solar panel. • Will navigate to the user autonomously • Can be operated via manual control
Software Overview • Embedded software for navigationand power control • iOS application for controlling PowerBot • Wi-Fi module embedded software for communication with iOS app
SoftwareLayout iOS Application MCU Embedded Software Embedded Navigation Algorithm Motor Control Power Management Servo Motors Sonar Sensors Solar Panel Charging Ports
iOSApp • Written in Objective-C using Xcode 4.4 • Offers multiple options for PowerBot: • Settings • Navigation • Manual • Statistics
iOS Views • Each view contains a separate viewController, allowing each tab to contain a unique layout of buttons and fields to be presented to the user.
socketConnect Creates socket to IP Address on a given port NSOutputStream NSInputStream sendMessage Sends message from output buffer receiveMessage Receives mesassage from input buffer Message Instance parseMessage Analyzes message to determine function
Wi-Fi Communication • Used as the primary mode of communication between PowerBot and the iOS Application. • 802.11 used as physical layer communication, with sockets used for higher level communication • RN-131 TCP/IP stack facilitates simpler TCP and UDP data transfer between PowerBot and its iOS App. Embedded Software iOS Software Application Layer Application Layer MCU - Serial iOS- Serial 802.11 - Socket 802.11 Socket
Wi-Fi Module - RN-131 • The Microchip RN-131 provides a complete Wi-Fi solution for onboard communication with PowerBot • The integrated TCP/IP stack within the RN-131 allows for easier implementation of sockets and passing data via TCP/UDP
RN-131 – Power Consumption • Provides low power • communication solution • 4uA Power Consumption when idle • 40 mA while active and connected • 140 mA Power while active and transmitting
Power 14V 14V Reg 5V 3.3V DC Motors • Servo Motors Inductive Charger 5V Reg PIC 32 Obstacle Avoidance 16V Wireles GPS Compass Serial Camera 3.3V Reg
Battery Requirement • 12 volt batteries • At least 2.4 Ah • Deep Cycle for increased usage time • low internal Resistance • High Depth of Discharge • Lightweight
Lithium Polymer Battery • Li-Pol 18650 Battery • 22.2 v (working) • 25.2 V (peak) • 15 V (cut-off) • Reasons for choosing • High energy density (Wh/kg) • High energy/dollar (Wh/$) • High charge efficiency (80-90%) • Low self-discharge
Alternative Power Source • Solar Panel: • Environmental Impact • Financial Benefits • Energy Independence
Increase the efficiency • Increase the size of the solar panel • Implement a tracking system • Single axis tracking system • Dual axis tracking system
comparison and decision • Dual axis require more maintenance • Extra cost for buying an extra motor or actuator • Complexity • 6% extra efficiency
How to implement • Rotate • Fixe the other angle At 15degree to have less losses
Servo motor Specification • Control System: +Pulse Width Control 1500usec Neutral • Required Pulse: 3-5 Volt Peak to Peak Square Wave • Operating Voltage: 6.0 Volts • Operating Speed : 0.15sec/60 degrees at no load • Stall Torque: 51 oz/in (3.7 kg/cm) • Current Drain: 7.7mA/idle and 180mA no load operating • Dimensions: 1.57" x 0.79"x 1.44" (40 x 20 x 36.5mm) • Weight: 1.52oz (43g) • Price: $12.95