Power Bot Group 2 Luke Cremerius Jerald Slatko Marcel Michael Tarik Ait 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 navigation and power control iOS application for controlling PowerBot Wi-Fi module embedded software for communication with iOS app

iOS Application Embedded Navigation Algorithm Motor Control Power Management Software Layout MCU Embedded Software Sonar Sensors Servo Motors Solar Panel Charging Ports

iOS App 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 sendMessage Sends message from output buffer receiveMessage Receives mesassage from input buffer parseMessage Analyzes message to determine function NSOutputStreamNSInputStream Message Instance

Wi-Fi Communication Used as the primary mode of communication between PowerBot and the iOS Application 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. Application Layer MCU - Serial Socket iOS - Serial Socket Application Layer Embedded SoftwareiOS Software

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 PIC 32 PIC 32 Inductive Charger GPS Compass Serial Camera DC Motors Obstacle Avoidance Obstacle Avoidance 5V Reg 3.3V Reg Wireles 16V 14V 5V 3.3V 14V Reg Servo Motors

Battery Requirement 12 volt batteries At least 2.4 Ah Deep Cycle for increased usage time low internal Resistance High Depth of Discharge Lightweight

SPECIFICATIONSNi-CdNi-MHLi-ionLi-Po Energy density (W·hr/kg)40– Capacity (Amp-hr) Internal resistance (mΩ) Nominal voltage (V) Discharge rateFlat Recharge life cycles >600>1000 DisposalMust be recycledRecyclable Charge/discharge efficiency70-90%66%80%-90%99.80% Cost ($/Whr) Battery Choice

Lithium Polymer Battery Li-Pol 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

Solar Panels Specifications MonocrystallinePolycrystallineThin film Power10W Open circuit voltage Short Circuit Current Maximum Power Voltage Maximum Power Current Efficiency15%12.5%6.3% Cost/W

Solar Power Selection Details Solar Panel TypeMonocrystalline ManufacturerINSTAPARK Power10 W Maximum Voltage Power17.5 Maximum Current Power0.57A Open Circuit Voltage21.95 V Cost$39.95

Increase the efficiency Increase the size of the solar panel Implement a tracking system Single axis tracking system Dual axis tracking system

Single Axis Control System Overview Ambient lightPhotoresistorMSP430 Longitude orientation

Dual Axis Control System Overview Ambient lightPhotoresistorMSP430 Latitude orientation Longitude orientation

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