tJ l .! 2008 CAS BattleBot by JAKE BARNHORST Submitted to the MECHANICAL ENGINEERING TECHNOLOGY DEPARTMENT In Partial Fulfillment of the Requirements for the Degree of Bachelor of Science m MECHANICAL ENGINEERING TECHNOLOGY at the OMI College of Applied Science University of Cincinnati May 2008 © ...... Jake Barnhorst The author hereby grants to the Mechanical Engineering Technology Department permission to reproduce and distribute copies of this thesis document in whole or in part. Signature of Author Mechanical Engineering Technology Accepted by University of Cincinnati College of Applied Science Middleweight BattleBot – Primary Weapon Jake Barnhorst Mechanical Engineering Technology ABSTRACT In the fall of 2008, the University of Cincinnati’s College of Applied Science (CAS) had no competitive representation for BattleBot competitions on the national level. A BattleBot is a robot which possesses fighting capabilities and competes against other BattleBots with the intent to disable them. Designing and constructing a strong competitive BattleBot for competition would lay a foundation for future Mechanical Engineering Technology Students and for CAS. The BattleBot competed in the BotsIQ Spring 2008 national competition in Miami Beach, Florida. The CAS BattleBot team consisted of Dave Bailey - Defense and Armor, Jake Barnhorst - Main Weapon, Tim Meyer - Drive Train and Control, and John Taphorn - Chassis. The main weapon is the component of the BattleBot which delivers the primary form of attack towards the opposing BattleBot. BattleBots compete one on one and the winner is determined by the Table 1 Offensive Capabilities Relative Weights amount of damaged Offensive Capabilities inflicted to the other. Weapon Causes extensive damage to opponent 0.06 The research concluded Weapon will not stall 0.054 that there are three primary types of Weapon system is repairable 0.051 BattleBots: Flipper Bots, Weapon operates seperately from all other components 0.042 0.032 Spinner Bots, and Dead Weapon system is interchangable Blow Bots. Table 1 shows the features developed from the research for a strong competitive BattleBot. This research resulted with the feature “weapon causes extensive damage to opponent” to have the highest relative weight at 6%. The “time it takes to switch out components” is the most important engineering characteristic relating to the design of the primary weapon having an overall importance rating of 16%. The objectives for the primary weapon upon completion were the following: • Would cause extensive visual damage to opponent • Primary weapon incorporated weldable materials, could be fully accessed upon removal of armor during repair, and no special tooling was required for repairs. • All repairs to primary weapon could be completed within 20 minutes including full replacement. • Robot would be able to drive and maneuver when primary weapon power system is disabled • The primary weapon had a complete back-up. To prove these objectives a combination of observations during the National Competition as well as controlled laboratory style testing was documented and recorded. The final budget for the main weapon of BattleBot was an estimated $2560 out of a total project budget of $16,800. The main weapon accounts for 15.2% of the total project budget. iii. The sponsors listed below have all donated or pledged funding in the amount of $6600 as well as various amounts of material and service donations totaling approximately $7200. The sponsors for the 2008 CAS Battlebot have provided all of the costs associated with the project. • Avenue Fabricating • Solid Works EDU • Makino • University of Cincinnati • RA Jones Mechanical Engineering • Duke Energy Technology Department • F & M Mafco • Tische Environmental • Aeronca Inc. • RME Machining • • UGS Blue Chip Tool • Meritor Webco • UGS/Engineering Methods The project schedule was followed as closely as possible because of the testing required prior to the competition. The deadline for the design freeze was December 14th. All manufactured parts must have been received from fabrication by January 29th. The robot was scheduled to be completely assembled by February 29th to meet the duration of testing which would extend from March 1st to April 26th. The Bots IQ National competition was held in Miami Beach, FL from April 30th through May 4th. The BattleBot, which was named “BearClaw” placed first in the 120lb college division as well as received the awards of “Best Engineered” and “Best Driver”. The main weapon worked flawlessly leading the robot to 6 straight victories with no mechanical failures. The robot was also displayed at the College of Applied Science’s Tech Expo which was May 22nd at the Duke Energy Center. iii. TABLE OF CONTENTS ABSTRACT .........................................................................................................................................................II TABLE OF CONTENTS .................................................................................................................................. IV LIST OF FIGURES ............................................................................................................................................. V LIST OF TABLES ............................................................................................................................................... V INTRODUCTION ................................................................................................................................................ 2 RESEARCH .......................................................................................................................................................... 2 ANALYSIS OF RESEARCH .............................................................................................................................. 4 OFFENSIVE ANALYSIS .................................................................................................................................... 4 PRIMARY WEAPON CHARACTERISTICS .................................................................................................. 5 PRIMARY WEAPON OBJECTIVES ................................................................................................................ 5 DESIGN CONCEPTS .......................................................................................................................................... 6 WEAPON TYPE.................................................................................................................................................... 6 WEAPON STYLE .................................................................................................................................................. 6 DESIGN SELECTION ........................................................................................................................................ 7 GENERAL ............................................................................................................................................................ 7 DRUM DESIGN .................................................................................................................................................... 7 BEARINGS AND ROTORS ..................................................................................................................................... 8 DRUM CROSS SECTIONAL ANALYSIS .................................................................................................................. 9 DRUM TEETH ANALYSIS ..................................................................................................................................... 9 MAIN WEAPON MOTOR .................................................................................................................................... 10 POWER TRANSMISSION ..................................................................................................................................... 10 BATTERY SELECTION ....................................................................................................................................... 10 FABRICATIO N AND ASSEMBLY ................................................................................................................ 11 SPECIALIZED MANUFACTURING ....................................................................................................................... 11 JOINING ............................................................................................................................................................ 12 ASSEMBLY........................................................................................................................................................ 12 PROOF OF DESIGN ......................................................................................................................................... 13 PROJECT MANAGEMENT ............................................................................................................................ 15 BUDGET ............................................................................................................................................................ 15 SCHEDULE ........................................................................................................................................................ 15 CONCLUSION ..................................................................................................................................................