1 CORP 4 CRITICAL DESIGN REVIEW OATS AUTOMATED CARRIAGE AUGUST 1, 2011 AUBURN UNIVERSITY MECHANICAL ENGINEERING DR. BEALE CORP 4 PROJECT MEMBERS BENJAMIN BETHEL GRAYSON DAWSON CODY OWEN KYLE PALMER DANIEL PAULK2 ABSTRACT: The aim of this project is to design, test, and manufacture an automated moving carriage that transports a receiver around a circular track. The design of the carriage will meet or exceed the requirements set forth by the sponsor, Neptune Technology. The carriage and track design must be developed according to the System’s Engineering process outlined in MECH-4240, Comprehensive Design 1. The purpose of this report is to detail and illustrate the progress made towards the embodiment of the final design by showing the steps of a proper design analysis. Important factors to be considered in this design include weight, cost, maintenance, and reliability, and a reduction of radio frequency interference due to physical components. The report will detail the subsystems developed for the final concept, the functions each subsystem accomplishes, and the parts and necessary cost and labor required for each subsystem. A manufacturing plan, as well as current efforts made in prototyping the final design will also be discussed. It should be noted that, while the report summarizes the conceptual design process (i.e. developing feasible alternatives to the solution), the primary goal of this report is to detail the engineering analysis for the chosen design.3 TABLE OF CONTENTS: Abstract 2 List of Figures 4 List of Tables 4 Introduction 5 Mission Objective 6 Architectural Design Development 7 • Development of Feasible Carriage Designs 7 • Concept Assessment and Determination of Final Design 8 • Product Hierarchy 9 • Economic Analysis 16 Requirements 18 Concept of Operations 18 Validate and Verify 20 Interfaces and ICD 21 Mission Environment 21 Technical Budget and Resource Tracking 21 Risk Management 22 Subsystems Design Engineering 22 Project Management 26 Conclusion 27 Appendix 284 LIST OF FIGURES: Figure 1 – Typical Signal Strength Plot 5 Figure 2 – Current Track Design 6 Figure 3 – Corp_4 Functional Decomposition 7 Figure 4 – Battery Operated/Wheel Driven Platform 9 Figure 5 – Motor and Gearbox 10 Figure 6 – Mechanical Drive System 11 Figure 7 – Track 12 Figure 8 – Chassis with Casters 13 Figure 9 – Platform 14 Figure 10 – Mast 15 Figure 11 – Concept of Operations Detail 18 Figure 12 – Midwest Motion Motor and Encoder 22 Figure 13 – Gear and Gear Rack 23 Figure 14 – Swivel and Rigid Casters 24 Figure 15 – 12 Volt Battery Pack 24 Figure 16 – Motor Controller 24V (Fully Assembled) 25 Figure 17 – Signal Hound Receiver 26 LIST OF TABLES: Table 1 – Concept Comparison Chart 8 Table 2 – Bill of Materials for Final Design 17 Table 3 – Teams and Tasks 26 Table 4 – Design Schedule 285 INTRODUCTION: Neptune Technology Group has been a major producer of water meters since 1892 and has over 119 years of experience in providing better-quality service to the water utility industry. They have been able to produce mobile data collectors such as the MRX920 that has the ability to take 5000 reads per hour along with being wireless and weighing less than 5 pounds. They are a well experienced and technologically advanced organization that will continue to be an aggressive competitor in the water utility industry. The projects taken on by Neptune Technology Group, such as the automated receiver, go to show that they are not slowing down anytime soon. Neptune currently has an outdoor test setup comprised of a rolling carriage on a 50 foot diameter circular track. A test water meter is placed in the center of the track and emits a wireless signal to a test antenna designed to measure the signal strength coming from the water meter. An example of a typical signal strength measurement is shown in Figure 1. The test antenna is mounted on the moving carriage and is moved to various locations around the track by two technicians who manually collect signal strength data from the receiver. This set-up is time consuming, uncomfortable, and inefficient. Since measurements are taken every 15 degrees, the current setup also has a low resolution and could be made much more accurate if automated. Figure 1 – Typical Signal Strength Plot6 The design task at hand is to create an automated carriage that will travel on a track 50 feet in diameter. The test antenna and receiver that measures the signal strength emitted by the test water meter will be mounted to the automated carriage, which will be remotely controlled from a base station or inside the Neptune Engineering building. The receiver will wirelessly send measurements of the signal strength for review by Neptune technicians and engineers. There are not currently any designs that will be sufficient at accomplishing this task, so the goal behind the design will be to create and manufacture this automated carriage from scratch. The current track design is shown below in Figure 2. Figure 2 – Current Track Design In this critical design review, a brief summary of feasible concepts for the automated carriage is presented as well as the assessment of these concepts and the selection of the final design. The development of each required subsystem is discussed as well as the integration of these subsystems and their parts into the final assembly. Plans for manufacturing and purchasing the required parts will also be included. MISSION OBJECTIVE: The overall purpose of this project is to design, evaluate, and create an automated test antenna that emits a low radio frequency and