2008 CAS Battlebot

tJ l .! 2008 CAS BattleBot

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

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.

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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.

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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 ...... 16 REFERENCES ...... 17 APPENDIX A – RESEARCH ...... A1

INTERNET RESEARCH ...... A1 INTERVIEW - MATT LUKES ...... A4 APPENDIX B – SURVEY RESULTS ...... B1

SURVEY RESULTS ANALYSIS ...... B2 SAMPLE CALCULATIONS - WEAPON CAUSES EXTENSIVE DAMAGE TO OPPONENT: ...... B3 APPENDIX C – BATTLEBOT QFD ...... C1

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APPENDIX D – BUDGET ...... D1 APPENDIX E – PROJECT SPONSORSHIP ...... E1 APPENDIX F – SCHEDULE ...... F1 APPENDIX G – SAMPLE CALCULATIONS ...... G1 APPENDIX H – CUSTOM PART DRAWINGS ...... H1 APPENDIX I – STANDARD PARTS DESCRIPTION ...... I1 APPENDIX J – MAIN WEAPON WIRING SCHEMATIC ...... J1

LIST OF FIGURES Figure 1 - Flipper Bot ...... 2 Figure 2 - Spinner Bots ...... 3 Figure 3 - Dead Blow Bot ...... 3 Figure 4 - "Hworf" Matt Lukes ...... 3 Figure 5- Final Weapon Style ...... 6 Figure 6 - Weapon Drive Train Schematic ...... 7 Figure 7- Weapon Energy ...... 7 Figure 8- Bearing and Rotor Stress ...... 8 Figure 9 - Bending Stress ...... 9 Figure 10 - Tooth Free Body Diagram ...... 9 Figure 11 - Main Weapon Drive Motor ...... 10 Figure 12 - Weapon simulator test results ...... 10 Figure 13 - Batteries ...... 11 Figure 14 - Bottle Bore Manufacturing ...... 11 Figure 15 - Weapon Component Breakdown ...... 12 Figure 16 - MIG Welding Components ...... 12 Figure 17 - Proof of Design Agreement ...... 13

LIST OF TABLES Table 1 Offensive Capabilities Relative Weights ...... 1 Table 2 - Main Weapon Features ...... 4 Table 3 - Main Weapon Survey Results Summary ...... 4 Table 4 - QFD Results ...... 5 Table 5 - Primary Weapon Objectives...... 5 Table 6 - Weapon Types ...... 6 Table 7 -Bill of Material ...... 13 Table 8 – Final Project Cost Breakdown ...... 15 Table 9 - Project Major Milestones ...... 15

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INTRODUCTION

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. The BotsIQ national competition for collegiate and high school levels was held in Miami Beach, Florida April 30th – May 4th and was an excellent chance for a team to represent CAS (1). The team built and competed in the 120lb weight class Post Secondary (collegiate) competition.

Designing and constructing a strong competing BattleBot for this competition laid a foundation for future Mechanical Engineering Technology (MET) students and for the college. 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. As an added bonus for building and competing in this competition, the college gained a major marketing tool. The BattleBot will aid in recruitment and publicity towards the MET department and towards the College of Applied Science.

RESEARCH

When researching ideas for the main weapon of the BattleBot, the internet and interviews with experts in the area proved to be the most beneficial tools. In the internet research section of Appendix A, five designs are shown which give a good representation of the different designs used during tournaments. The weapons types in this section are classified into three categories: flippers, spinners and dead blows. A flipper BattleBot is one whose primary form of attack is to flip its opponent on its back disabling it from competition. Figure 1 shows a typical Flipper Bot (2). The mechanical arm on the front of the robot uses pneumatics or a high torque motor to create a strong vertical thrust which is capable of throwing the opponent up into the air. Flipping an opponent over usually disables robots which are not capable of driving Figure 1 - Flipper Bot upside down. Mechanical arms used in flipper bots can be complex and break easily if not reinforced in critical stress areas.

A Spinner Bot is one whose uses a high speed spinning weapon to deliver repeated blows to its opponent using inertia. In Figure 2, three common forms of spinning weapons are seen (3). Each of the designs in Figure 2 has a rotating mass on the front end of the robot. The purpose of this rotating mass is to use the rotational inertia created by the spinning mass to transfer a massive blow to the competitor. Large forces are usually delivered by these types of weapons and when designed properly can potentially create the most damage of any of the weapon types. The large amount of force delivered by these weapons can cause repercussions such as damage to the robot during the reaction of a blow and difficulty

maneuvering robot due to the gyroscopic forces.

Figure 2 - Spinner Bots

A dead blow BattleBot uses a heavy solid object attached to a mechanical arm which swings back and forth hitting its opponent. Dead blow bots can utilize tremendous amounts of force to either pierce through or crush the opposing robots armor damaging the internals and possibly disabling it. The famous BattleBot named “Dead Blow” can be seen in Figure 3 (4). Similar problems cans occur with the dead blows as the flipper bots. Mechanical arms have to withstand enormous amounts of force and overdesign usually adds precious weight to the robot.

On September 14th, 2007 the team went to the home of BattleBot Champion and builder of two BattleBots, Matt Lukes. At his home in Erlanger, Kentucky, Matt showed the team his championship BattleBot Hworf which can be found in the interview section of Appendix A as well as in Figure 4 (5). Hworf is classified as a spinner BattleBot because it uses a heavy solid steel manufactured blade which spins at Figure 3 - Dead Blow Bot 1300 rpms. The team witnessed the main weapon of Hworf in person and through recorded DVD matches to see the full potential of a spinner bot in a match (6). The advice which the team received from Matt through the interview was “The key to winning is spinning” (5). Matt explained that in all of his years of experience, the robots which cause the most damage in his opinion are the Spinner Figure 4 - "Hworf" Matt Lukes Bots. Matt also recommended designing the weapon system as being independent from the rest of robot specifically the drive train. This independence is beneficial because if for some reason the weapon power supply is to become disabled due to a blow from an opponent, the robot would still be able to drive around the arena which would not knock it out of the competition.

ANALYSIS OF RESEARCH

The features of the primary weapon are listed in Table 2 and ultimately resulted in the objectives for the main weapon.

Table 2 - Main Weapon Features Main Weapon Features Description Weapon causes extensive damage to Significant noticeable damage to components of opponent. opposing robot During Battle, the main weapon should have enough Weapon will not stall. torque that it should be allowed to stall and cause massive amperage spike s If main weapon's vital components are damaged Weapon operates seperately from all which disables the weapon, the BattleBot's drive train other systems. and power supply should still be functional Minor damage to main weapon should be easily Weapon system is repairable. fixable between matches. For instance weldability. If a need arises where the weapon becomes damaged Weapon system is interchangable. beyond simple repair, it should be able to be easily removed from system and replaced with a back-up

OFFENSIVE ANALYSIS

The most important feature to have in the primary weapon was influenced by thirteen experienced designers, builders, and competitors in the field of BattleBots. Table 3 shows Table 3 - Main Weapon Survey Results Summary the summary of those survey Note: All values on scale of 1-5 results pertaining to the 2.385 Offensive Capabilities Average main weapon of the BattleBot. Main Weapon Features Average from Frequencies The experienced Weapon causes extensive damage to opponent. 3.8 designers and Weapon will not stall. 3.4 builders Weapon system is repairable. 3.2 concluded that Weapon operates seperately from all other systems. 2.6 the “Weapon Weapon system is interchangable. 2.0 causes extensive damage to opponent” is the most important feature to have with an average score of 3.8 out of 5 and a relative weight of approximately 6%. The complete project survey can be found in Appendix B. When compared to the three other areas of BattleBot’s features, the Offensive Capabilities was third out of the four with an average score of 2.4 out of 5.

The results for the weighting factor calculations can be found in the Survey Results Analysis of Appendix B. The method used to obtain a useful weighting factor for each subcategory can be found in the Sample Calculations section of Appendix B.

PRIMARY WEAPON CHARACTERISTICS

All characteristics which relate to Table 4 - QFD Results Relative the Offensive Capability features Features (customer Engineering Characteristic which importance of can be seen in Table 4. Note that requirements) satisfies features characteristic Time it takes to fully only the engineering characteristics Weapon System is repairable change out components 16% with the strongest relationship in Amount of torque available Weapon w ill not stall to rotating components 11% each category were listed. At 16% Weapon system is Number of back-up relative importance, the “time it interchangeable components 11% takes to fully change out Weapon operates seperately Number of independent from all other components subsystems 10% components” is the most important characteristic carrying a Weapon System is repairable Properties of Materials 8% relationship to the main weapon. In Weapon w ill not stall Battery rating 8% Table 4 the engineering Weapon operates seperately Number of sides robot characteristics are sorted from from all other components can operate on 7% having the greatest relative Number and size of Weapon System is repairable robot components 7% importance value to the least. The Weapo n causes extensive Amount of force delivered larger the value of relative 4% damage to opponent by weapon importance means that those characteristics have a greater affect on customer satisfaction. To see the complete relationship matrix and the QFD see Appendix C.

PRIMARY WEAPON OBJECTIVES

The objectives for the primary were proven primarily through observation during the Table 5 - Primary Weapon Objectives

Offensive Capabilities Objectives 1. A minimum of one part such as fender or section of armor will be seperated from opposing battlebot Weapon Causes extensive 2. Will cause opponent to flip upside down damage to opponent 3. Forceful blow will be delivered to critical components of opposing battlebot such as wheels or protected power system 1. Weapon will have adequate torque to lift 120 lb robot when placed on top of weapon Weapon will not stall 2. Weapon speed will not reduce more than 50% of rated weapon speed when delivering blow to opponent. 1. Primary weapon repair incorporates weldable materials, can be fully accessed upon removal of armor, and no special tooling will be Weapon system is repairable required for repairs. 2. All repairs to primary weapon can be completed within 20 minutes . Weapon operates seperately 1. Robot will be able to drive and manuever when primary weapon from all other components power system is disabled 1. Primary weapon has complete back-up Weapon system is 2. Primary weapon can be can be completely replaced within 20 interchangable minutes 5

competition in Miami. Each match was recorded via digital video for proof of objectives. All objectives listed, were successfully met. The objectives for the capabilities “weapon will not stall” and “weapon operates separately from all other components” were proven through controlled tests which demonstrated each of the remaining objectives shown in Table 5. The tests were performed in the back parking lot of the CAS North Lab and demonstrated to the advisor Dr. Janet Dong. The successful completion of the tests fulfilled requirements set by the proof of design agreement.

DESIGN CONCEPTS

WEAPON TYPE The design for the weapon had multiple paths. Table 6 shows the possible selections for the weapon.

Table 6 - Weapon Types Weapon Type Description Inertia Spinner Uses the inertia of large rotating masses to inflict damage Basic Wedge Uses “wedge” style body to manipulate Flipper Bot Flipping mechanism tips battlebot over on its back where it can’t move Full Body Spinner Uses entire body and frame of robot as a weapon by spinning it around itself Dead Blows Uses hammer-like mechanism to swing at opponent with large masses or puncturing weapons.

The inertia spinner design became the final selection for the weapon of the BattleBot. The basic wedge, flipper Bot, and dead blow were eliminated immediately because causing damage is minimal in most cases as was proven during the research. The full body spinner is capable of causing the most damage but usually is the hardest to control due to the reaction forces caused by the attacks. The inertia spinner is the most practical because of the balance of controllability and the amount of damage it is capable of causing.

WEAPON STYLE

Figure 2 and Figure 4 of the Research section shows various styles of inertia weapons. Figure 5 shows the final weapon style which was used in the BattleBot. This style of inertia spinner is called a

6 Figure 5- Final Weapon Style

“drum” weapon because of its cylindrical shape and nature. The energy of the rotating mass of the drum is translated through the projections on the drum called teeth and into the opponent causing damage.

DESIGN SELECTION

GENERAL

The weapon was broken up into four sections: the main body, the end caps and rotors, weapon teeth, and the motor and drive train. Figure 6 shows the basic schematic of the weapon drive train. The drum is driven by a motor via a pulley and v-belt configuration. The 120 pound weight limit for the competition drove many of the geometric decisions in this design specifically limiting the drum thickness to ¼ inch.

Figure 6 - Weapon Drive Train Schematic

DRUM DESIGN

To meet the 120 pound weight requirement, the drum was designed to be hollow. Since the majority of the mass of the drum is on the outermost radius, the drum was considered a flywheel for the stress analysis. Figure 7 shows the energy equation for a rotating body. This equation was ultimately used in the design but

Figure 7- Weapon Energy

Wv 2 compared with the equation E = which was taken from the Machinery’s Handbook for 2G flywheels. The results came within 2% of the final value of 12,328 lbs of force; therefore; the original assumptions were correct. When using the energy equation from Machinery’s Handbook, it was assumed that 50% of the total energy would be delivered during a blow because the full amount of energy available by the drum will not be released due to deflections and reactive motions. It was found that this equation was incorrect therefore the rotational energy equation was used and only compared with the results from prior assumptions. Appendix H shows the sample calculations for the energy of the drum used to determine the forces needed for the strength of materials.

BEARINGS AND ROTORS

The drum rides on 1.5” inch rotors which are stepped down from the 3” diameter drum. The rotors ride in bearings simply supported on both sides. Bearing stress and stress concentration for the step was considered. Figure 8 shows the free body diagrams for the analysis as well as the geometrical results. Bronze sleeve bearings were selected because they are inexpensive, easy to replace and robust. They were also chosen because they provided the least possibility of a mechanical failure during a three minute match. The load ratings are not as high for Figure 8- Bearing and Rotor Stress sleeve bearings but these will be ideal for a three minute match. The rotor step stress is greater than the allowable stress but the welded teeth will act as ribs providing greater resistance towards bending. This is impossible to calculate but it will be assumed that the stress will be less and the geometry will be sufficient. Weight also played a factor in this decision because the geometry has to be weight efficient at all costs. The sample calculations for bearing and rotor step stress can be found in Appendix G and the drawings can be found in Appendix H under the heading “End caps/rotors”.

DRUM CROSS SECTIONAL ANALYSIS

Due to weight, the drum was designed to be hollow. Therefore bending stress must be considered because of the cross sectional properties. The force delivered by the weapon will cause a reaction force on the drum seen in Figure 9. The cross section of the drum can be seen in Figure 9 as well. The sample calculations for the stress due to bending can be found in Appendix G. The drawing in Appendix H titled “Main Weapon Body” shows the internal and external dimensions of the main body of the weapon.

Figure 9 - Bending Stress

DRUM TEETH ANALYSIS

The teeth are welded to the drum and to figure the amount of weld bead to be applied, a free body diagram was created and can be seen in Figure 10. The bending moment was figured using the numbers shown. It was determined that an all around weld bead of .3 inch throat thickness was needed. The sample calculations for the tooth stress can be found in Appendix G and the tooth drawings can be found in Appendix H under the heading “Weapon Teeth”.

Figure 10 - Tooth Free Body 9 Diagram

MAIN WEAPON MOTOR

To drive the weapon a brushed 24V DC motor was chosen. The motor chosen was manufactured by Magmotor and its specs are listed below. The Magmotor was chosen because it has the highest power to weight ratio for a motor this size. Appendix I shows a complete list of the specs for the main weapon motor.

Figure 11 - Main Weapon Drive Motor

POWER TRANSMISSION

The power transmission system for the main weapon from the motor is a pulley and V-belt system. This set up is ideal because the V-belt allows for slight lateral movement which will most likely occur during battle unlike a chain and sprocket system. The sample calculations for the V-belts and pulleys can be found in Appendix G and the specifications can be found in Appendix I.

Keys will be used to fix the pulleys to the motor shaft. Besides the 1.7 inch length of shaft protruding from one side of the motor, there is a .7 inch length of shaft protruding from the opposite end which will be utilized as a redundant drive pulley. A standard 1/8 inch key is used for the long shaft but a 3/16” key was needed to compensate for the shorter shaft. The key sample calculations can be found in Appendix G.

BATTERY SELECTION

To properly size the batteries, there was no accurate calculation available for calculation amperage use over time. Consequently,

10 Figure 12 - Weapon simulator test results

a weapon simulator was fabricated using the purchased Magmotor. An ammeter was attached to the leads to test for amperage draw. The test results and weapon simulator can be found in Figure 12. The sample calculations for battery sizing can be found in Appendix G.

It was determined that two (2) 24V 3.3 A-h Batteries will be used to power the motor. These can be seen in Figure 13. The two 24V batteries will be wired in parallel to double the amperage to the system. The sample calculations for the battery sizing can be found in Appendix G and the specifications can be found in Appendix I.

Figure 13 - Batteries

FABRICATIO N AND ASSEMBLY

SPECIALIZED MANUFACTURING

A specialized manufacturing process was needed for the creation of the main body of the weapon. The weight restriction limited the thickness of the drum wall to ¼”. A greater thickness of material was needed in the areas of the body where the grooves for the V-Belts needed to be machined. To keep the ¼” thickness in the space between the belt grooves, a process called bottle boring utilized. The bottle Figure 14 - Bottle Bore Manufacturing boring process consists of boring out the center of a cavity whose diameter is larger than the area available to enter that cavity. A section of the drum body where the process was needed is seen in Figure 14. All other machining needed for the

weapon was done through conventional means.

JOINING

The main weapon design consisted of a three component system: the drum body, the rotors, and the teeth. Each of these can be seen in Figure 15. In order for these three components to form the final assembly, the MIG welding process was chosen to join them. The MIG welding process was the fastest and provided adequate strength for the joining the parts. The completed welded joints can be seen in Figure 16.

Figure 15 - Weapon Component Breakdown

Figure 16 - MIG Welding Components

ASSEMBLY

To fully assemble the weapon requires only minimum parts and tooling. Table 7 shows the bill of materials for the main weapon.

Table 7 -Bill of Material

Part Quantity Description Material

drum body 1 ¼” machined hollow drum 8620 steel rotor 2 solid machined 8620 steel teeth 20 1.5” x .75” x .5” machined 8620 steel bearing 2 oilite sleeve bearing bronze motor mount 2 weapon motor mount 6061 alum motor 1 s28-400 magmotor 4.5 HP @ 4500rpm - battery 2 3.3 A-h Ni pulley 2 2.5” OD x ½“ bore A -profile 1020 steel belt 2 AX-20 Cogged V-belt key 1 1/8” x 1/8” x 1.5” 1020 key 1 3/16 x 3/16 x .75 1020 bolt 4 ¼-20 cap head screws holly-chrome

PROOF OF DESIGN

Figure 17 shows each design agreement set for the main weapon portion of the project. The “weapon is repairable” was met because an 8620 steel was chosen for all components which provided excellent welding properties. The weapon during testing was found to require less than .5 seconds to fully spin

Proof of Design Statement Met Criteria? Weapon system is repairable Yes Is at max velocity in less than 1 sec Yes Weapon can be repaired/replaced within 20 minutes Yes Causes extensive visual damage to opponent Yes

Figure 17 - Proof of Design Agreement up to max speed which met design criteria two. During the competition, a spacer for the weapon was placed in backwards causing it to seize. The team was allotted 20 minutes to fix the problem. In order to fix the problem, the weapon had to be completely taken out and assembled again. The time needed for this operation was only 15 minutes which satisfies design agreement three. Design agreement four required visual evidence of damage sustained to opponents during a match and is proven through the evidence shown in Figures 18 and 19.

13 Figure 18 – Damaged Opponents

Figure 19 – Damaged Opponents

PROJECT MANAGEMENT

BUDGET

The final project cost summary can be seen in Table 8. For the robot, there was almost a $3000 difference in proposed to Table 8 – Final Project Cost Breakdown actual because of the fact that all of the material and labor were provided from our sponsors including the necessary funding, The actual project total came to $16,800 which included all robot costs as well as competition and miscellaneous costs. The complete budget breakdown can be seen in Appendix D with the sponsorship specifics being found in Appendix E.

SCHEDULE

Table 9 - Project Major Milestones

Table 9 shows the final breakdown of the milestones for scheduling as well as the reasons for which those deadlines where not met.

CONCLUSION

Through the testing and results from the competition, the main weapon was adequately designed for use in the combat robots world. The combination of a strong and robust design paired with proper component selection provided the best design choices for the application. By achieving the design agreement, the weapon met and exceeded the demands of the competition and the unknowns of the opponents it faced. During the competition, the 2008 CAS BattleBot placed first in the 120lb collegiate division winning all but the opening match. Some teams who were amongst the competition included the University of Miami Florida, the Georgia Institute of Technology, and the University of Puerto Rico. As well as the first place finish, the BattleBot also claimed the “Best Engineered” award and the team received the “Best Driver” award.

For future teams, two suggestions come to mind. One would be a more sustainable teeth profile design. During the competition and testing, many of the teeth lost their original profile and became dull. A suggestion would be to research a way to harden or use a different material for the teeth design. The other suggestion involved a more reliable belt tensioning device. The installed device functioned by required constant tuning to keep the proper tension on the V-belts.

REFERENCES

1. Rules and Regulations. BotsIQ: Robotics Education. [Online] BattleBots Inc. . [Cited: September 28th , 2007.] http://botsiq.com/rules.php. 2. Bio-Hazard Combat Robot. Robot Books. [Online] [Cited: October 1st, 2007.] http://www.robotbooks.com/biohazard.htm. 3. Garrett, Robert, et al. Project Muthar: BattleBot. Cincinnati : University of Cincinnati College of Applied Science , 2002. 4. —. Project Muthar. Cincinnati : University of Cincinnati , 2002. 5. Lukes, Matt. BattleBot Building and Fighting Tips. Cincinnati, September 14, 2007. 6. Metal Munching Maniacs: Gourmet Damage DVD. AnimEigo, 2004. 7. Motors. Robot Market Place. [Online] [Cited: October 17th , 2007.] http://www.robotmarketplace.com/marketplace_motors.html. 8. Industrial Press. Machinery's Handbook. 26. New York : Industrial Press Inc. , 2000.

APPENDIX A – RESEARCH

INTERNET RESEARCH • If flipped no rectification (may run upside down)

• Doesn’t look to be heavily armored

Spare Parts from BattleBots Project Muthar report • Two wheels • Spinning weapon (cutting damage) • Chain drive • Maneuverable

• If flipped no rectification (may run upside down)

• Doesn’t look to be heavily armored

Garm from BattleBots Project Muthar report • Four wheels • Spinning weapon (cutting damage) • Protected wheels

Appendix A1

• Easily flipped

• Wheels exposed

Dead Blow from BattleBots

Project Muthar report http://en.wikipedia.org/wiki/Deadblow • Four wheels • Impact damage • Weapon can flip bot over • Angled armor

• Extremely complex – War Head from Project lots can go wrong Muthar report http://images.google.com/imgres?imgurl=http:// • Slow moving, lacks www.robotcombat.com/images/warhead_hole1.j pg&imgrefurl=http://www.robotcombat.com/ni maneuverability ghtmare_sf02.html&h=542&w=720&sz=64&hl =en&start=10&um=1&tbnid=riOYaG4qa0QwJ • Gyroscopic force tends M:&tbnh=105&tbnw=140&prev=/images%3Fq %3Dbattlebot%2Bwarhead%26svnum%3D10% to flip robot 26um%3D1%26hl%3Den%26sa%3DG Robot Combat.com

This is classified as a “spinner bot”. Won many competitions. Unique design

• High speed, high inertia spinning weapon • Actuated arms for flipping back over • Highly destructive

Appendix A2

• Battery powered • Constructed of light materials • Weapon powered linear actuators • Mag motors • Chain driven

http://www.robotbooks.com/biohaz ard.htm 10/01/07

When building battlebot the most important factor is your weight limit. When building a battlebot you want to put the most power, thickest armor, and biggest weapon. Winner of battlebot competition.

• 220 lbs. • Battery powered • Titanium, Magnesium, Aluminum, Steel • Heavy-duty frames • Light-weight base plates and bulkheads • Complete drive trains • Built-in motor and speed controller mounting • Custom wheels

Appendix A3

INTERVIEW - MATT LUKES • Be able to be flipped • Meet weight requirement • Swinging blade • Able to push competitor bot

Interview notes with Matt Lukes; building BattleBots for 7 years, competed in BotsIQ, 9/14/07 won multiple tournaments at the Robot Club Matthew Lukes and Grill Interview

• “ The key to winning is spinning” • Spinning weapons need to be up to fighting speed in under 2 Hworf seconds • The robot must be able to Battlebot champion and creator of two battlebots. continue to fight even if being Armor for bottom made of a sheet of titanium and flipped upper armor was Lexan. The frame was made of • aluminum extrusion. Powered by three batteries. A good type of armor Matt has Weapon was a 60 lbs swinging lawn mower used with experience is one which blade. Drive train was driven by chains. has air gaps in the middle which tend to be more rigid than just a • 120 lbs solid piece of material. • Swinging blade • The design of the robot should • Bot should be able to push 240 lbs incorporate ease of repairs to • Can be flipped benefit the competition. • Practice with the robot for numerous weeks and in different situations to prep for battle. • Have lots of spare parts on hand.

Appendix A4

APPENDIX B – SURVEY RESULTS

CAS BattleBot We are a group of seniors from the University of Cincinnati studying A total of 13 completed surveys were collected Mechanical Engineering Technology. We are developing a BattleBot to from various builders and competitiors who compete at the 2008 BotsIQ competition. Please take a moment to review have had numerous years of experience in the the following survey and in your best opinion, rank the importance of each area item. Please rank each category. Once you have ranked the category rank each subcategory within the main category.

Main Category (1-least important, 5-most important) • 2.385 (4) 2 (2) 3 (5) 4 (2) Offensive Capabilities 1 • Defensive Capabilities 2.615 1 (3) 2 (3) 3 (3) 4 (4)

• 3.154 1 (1) 2 (2) 3 (4) 4 (6) Maneuverability and Control • 1.846 1 (5) 2 (6) 3 (1) 4 (1) Maintenance 2.385 Offensive Capabilities (1-least important, 5-most important) Weapon causes extensive damage • 3.769 1 (2) 2 (1) 3 (1) 4 (3) 5 (6) to opponent. • Weapon will not stall. 3.385 1 (1) 2 (1) 3 (5) 4 (4) 5 (2)

Weapon operates seperately from all • 2.615 1 (3) 2 (4) 3 (2) 4 (3) 5 (1) other systems. • Weapon system is interchangable. 2.000 1 (6) 2 (5) 3 (0) 4 (0) 5 (2)

• Weapon system is repairable. 3.231 1 (1) 2 (2) 3 (5) 4 (3) 5 (2)

2.615 sum= 15.000

Defensive Capabilities (1-least important, 4-most important) • Inversion is non-disabling. 3.077 1 (3) 2 (0) 3 (3) 4 (7)

Armor capable of • 3.000 1 (0) 2 (3) 3 (7) 4 (3) sustaining/deflecting damage. • 2.385 1 (0) 2 (10) 3 (1) 4 (2) Armor is modular. • 1.538 1 (10) 2 (0) 3 (2) 4 (1) Frame is modular. 3.154 sum= 10.000

Maneuverability and Control (1-least important, 6-most important) Able to keep opponent in front at all • 3.385 1 (1) 2 (1) 3 (5) 4 (4) 5 (2) 6 (0) times. • Control system is adaptable. 2.615 1 (3) 2 (5) 3 (3) 4 (0) 5 (0) 6 (2)

Robot should be easy and simple to • 4.308 1 (1) 2 (1) 3 (0) 4 (5) 5 (3) 6 (3) control. Drive system able to move • 3.692 1 (0) 2 (2) 3 (4) 4 (3) 5 (4) 6 (0) opponent. Power Supply is able to last 3 • 4.615 1 (1) 2 (2) 3 (1) 4 (0) 5 (2) 6 (7) minutes. • Electrical systems are redundant. 2.154 1 (8) 2 (2) 3 (0) 4 (0) 5 (2) 6 (1)

1.846 sum= 20.769 Maintenance (1-least important, 4-most important) • Repairs completed quickly and easily. 2.769 1 (2) 2 (3) 3 (4) 4 (4) • Batt ery supply charges in 20 minutes. 2.154 1 (5) 2 (4) 3 (1) 4 (3) • Battery supply is easily replaced. 2.769 1 (2) 2 (4) 3 (2) 4 (5) • Parts are easily removed. 2.308 1 (4) 2 (2) 3 (6) 4 (1)

Thank you for taking the time to fill out our Survey. We appreciate you taking the time.

Appendix B1

SURVEY RESULTS ANALYSIS

Note: All data frequencies below correspond to the survey questions above Frequencies (x) Total Mean 3 (5) 4 (2) 13 2.385 1 (4) 2 (2) 1 (3) 2 (3) 3 (3) 4 (4) 13 2.615

(1) (2) 3 (4) 4 (6) 13 3.154 1 2 (5) (6) 3 (1) 4 (1) 1 2 13 1.846

3 (1) 4 (3) 5 (6) 13 3.769 1 (2) 2 (1) 1 (1) 2 (1) 3 (5) 4 (4) 5 (2) 13 3.385

(3) (4) 3 (2) 4 (3) 5 (1) 13 2.615 1 2 1 (6) 2 (5) 3 (0) 4 (0) 5 (2) 13 2.000

1 (1) 2 (2) 3 (5) 4 (3) 5 (2) 13 3.231

3 (3) 4 (7) 13 3.077 1 (3) 2 (0) 1 (0) 2 (3) 3 (7) 4 (3) 13 3.000

(0) (10) 3 (1) 4 (2) 13 2.385 1 2 1 (10) 2 (0) 3 (2) 4 (1) 13 1.538

1 (1) 2 (1) 3 (5) 4 (4) 5 (2) 6 (0) 13 3.385 1 (3) 2 (5) 3 (3) 4 (0) 5 (0) 6 (2) 13 2.615 1 (1) 2 (1) 3 (0) 4 (5) 5 (3) 6 (3) 13 4.308 1 (0) 2 (2) 3 (4) 4 (3) 5 (4) 6 (0) 13 3.692 1 (1) 2 (2) 3 (1) 4 (0) 5 (2) 6 (7) 13 4.615 1 (8) 2 (2) 3 (0) 4 (0) 5 (2) 6 (1) 13 2.154

3 (4) 4 (4) 13 2.769 1 (2) 2 (3) 1 (5) 2 (4) 3 (1) 4 (3) 13 2.154

(2) (4) 3 (2) 4 (5) 13 2.769 1 2 1 (4) 2 (2) 3 (6) 4 (1) 13 2.308

Appendix B2

Weighted Sxx Value to be C1 C1 x Sxx submitted in

QFD 23.8% 25.1% 6.0% 3.72 23.8% 22.6% 5.4% 3.34 23.8% 17.4% 4.2% 2.58 23.8% 13.3% 3.2% 1.98

23.8% 21.5% 5.1% 3.19

26.2% 30.8% 8.0% 5.00 26.2% 30.0% 7.8% 4.88 26.2% 23.8% 6.2% 3.88 26.2% 15.4% 4.0% 2.50

31.5% 16.3% 5.1% 3.19 31.5% 12.6% 4.0% 2.47 31.5% 20.7% 6.5% 4.06

31.5% 17.8% 5.6% 3.48

31.5% 22.2% 7.0% 4.35 31.5% 10.4% 3.3% 2.03

18.5% 27.7% 5.1% 3.18 18.5% 21.5% 4.0% 2.47 18.5% 27.7% 5.1% 3.18 18.5% 23.1% 4.3% 2.65

SAMPLE CALCULATIONS - WEAPON CAUSES EXTENSIVE DAMAGE TO OPPONENT:

= = 1 11 𝑚𝑚𝑎𝑎𝑎𝑎𝑎𝑎 𝑐𝑐𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 𝑠𝑠𝑠𝑠𝑠𝑠 −𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐 𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚

𝐶𝐶 2.385𝑠𝑠𝑠𝑠𝑠𝑠 𝑜𝑜𝑓𝑓 𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 𝑐𝑐𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 𝑚𝑚𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒 𝑆𝑆 𝑠𝑠𝑠𝑠3𝑠𝑠.769𝑜𝑜𝑓𝑓 𝑠𝑠𝑢𝑢𝑢𝑢 −𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐 𝑚𝑚𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒 = 23.8% = = 25.1% × = 6% 1 10 11 15 11 1

𝐶𝐶 𝑆𝑆 𝑆𝑆 𝐶𝐶 × = 11 1 × 5 11× 1 6% 𝑆𝑆 𝐶𝐶 = × 5 = 3.7 𝑊𝑊𝑒𝑒𝑒𝑒𝑒𝑒ℎ𝑡𝑡𝑡𝑡𝑡𝑡 𝑉𝑉𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 𝑡𝑡𝑜𝑜 𝑏𝑏𝑒𝑒 𝑠𝑠𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑡𝑡𝑡𝑡𝑡𝑡 𝑖𝑖𝑛𝑛 𝑄𝑄𝐹𝐹𝐹𝐹 �8𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿% 𝑆𝑆 𝐶𝐶 𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝 � Appendix B3 𝑊𝑊𝑒𝑒𝑒𝑒𝑒𝑒ℎ𝑡𝑡𝑡𝑡𝑡𝑡 𝑉𝑉𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 𝑡𝑡𝑜𝑜 𝑏𝑏𝑒𝑒 𝑠𝑠𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑡𝑡𝑡𝑡𝑡𝑡 𝑖𝑖𝑛𝑛 𝑄𝑄𝐹𝐹𝐹𝐹 � �

APPENDIX C – BATTLEBOT QFD

9= Strong 3=Moderate 1=Weak

delivered by weapon Amount ofAmount torque available to components rotating ofNumber independent subsystems Number of back-up components Time it takes to fully change out components of sides robot Number can operate on Properties of Materials ofNumber size and robot components speedTurning of robot Programability coefficientFriction of tires rating Battery Time required to completely charge battery ImportanceCustomer Relative Weight Offensive Capabilities Weapon Causes extensive damage to opponent 9 9 3 3 3.72 0.0599 Weapon will not stall 3 9 3 3.34 0.0538 Weapon operates seperately from all other components 9 1 1 2.58 0.0415 Weapon system is interchangable 3 9 3 1.98 0.0319 Weapon system is repairable 3 9 9 3 3.19 0.0513 Defensive Capabilities Inversion is non-disabling 9 3 5 0.0805 Armor capable of sustaining deflecting damage 9 3 4.88 0.0785 Armor is Modular 3 9 9 3 3.88 0.0624 Frame is Modular 3 9 9 3 2.5 0.0402 Maneuverability and Control Able to keep opponent in front at all times 3 9 3 1 3.19 0.0513 Control system is adaptable 3 9 2.47 0.0398 Robot should be easy and simple to control 3 9 3 4.06 0.0653 Drive system is able to move opponent 9 9 3 3.48 0.0560 Power supply is able to last 3 minutes 3 9 3 4.35 0.0700 Electrical systems are redundant 9 3 1 2.03 0.0327 Maintenance Repairs completed quickly and easily 3 3 9 9 3 3 3.18 0.0512 Battery supply charges in 20 minutes 9 9 2.47 0.0398 Battery supply is easily replaced 3 9 3 3.18 0.0512 Parts are easily removed 9 3 9 3 2.65 0.0427 Absolute Importance 0.70 1.89 1.73 1.94 2.79 1.23 1.50 1.17 0.66 1.34 0.75 1.50 0.57 62.13 1 Relative Importance 0.0394 0.1065 0.0973 0.1092 0.1570 0.0691 0.0846 0.0656 0.0371 0.0755 0.0423 0.0843 0.0320

Appendix C1

APPENDIX D – BUDGET

Trip Expenses (Before Donations) Trip Expenses (After Donations) Competition Entry fee $500.0 Competition Entry fee N/A Hotel Expense - 2 rooms @ 150/night -5 nights $1,500.0 Hotel Expense - 2 rooms @ 150/night -5 nights N/A Rental Van + Insurance $500.0 Rental Van + Insurance N/A Gas @ 3.00/gal assumed 2400 miles @ 10mpg $840.0 Gas @ 3.00/gal assumed 2400 miles @ 10mpg N/A Team shirts $250.0 Team shirts N/A Total Trip Expenses $3,590.0 Total Trip Expenses $0.0

BattleBot Expenses (Before Donations) BattleBot Expenses (After Donations) Drive Train (Tim Meyer) Drive Train (Tim Meyer) Batteries (4 @ $172/pack) $688.0 Batteries (4 @ $172/pack) $688.0 Battery Chargers (2 @ $100) $200.0 Battery Chargers (2 @ $100) $200.0 Remote control $300.0 Remote control $300.0 Speed Controllers (4 @ $215) $860.0 Speed Controllers (4 @ $215) $860.0 Gear Boxes (3 @ $450) $1,350.0 Gear Boxes (3 @ $450) $1,350.0 Drive motors (4 @ $315) $1,260.0 Drive motors (4 @ $315) $1,260.0 Drive wheels $100.0 Drive wheels $100.0 Fasteners $30.0 Fasteners $30.0 Bearings $50.0 Bearing s $50.0 Motor Mounts $30.0 Motor Mounts $30.0 Axle Material $15.0 Axle Material $15.0 Axle Fabrication $30.0 Axle Fabrication $30.0 Drive Train Total $4,913.0 Drive Train Total $4,913.0 Main Weapon (Jake Barnhorst) Main Weapon (Jake Barnhorst) Weapon Motor $750.0 Weapon Motor $750.0 Weapon Motor Mount Material $15.0 Weapon Motor Mount Material $15.0 Weapon Motor Mount Fabrication $30.0 Weapon Motor Mount Fabrication N/A Weapon sheaves and belts $50.0 Wea pon s heaves a nd belts $50.0 Weapon material $100.0 Weapon material $100.0 Weapon fabrication $150.0 Weapon fabrication N/A Batteries (4 @ $172/pack) $688.0 Batteries (4 @ $172/pack) $688.0 Speed Controllers 3 @ $215 $645.0 Speed Controllers 3 @ $215 $645.0 Bearings $50.0 Bearing s $50.0 Fasteners $30.0 Fasteners $30.0 Wiring $50.0 Wiring $50.0 Main Weapon Total $2,558.0 Main Weapon Total $2,378.0 Frame (John Taphorn) Frame (John Taphorn) Chassis material $300.0 Chassis material $300.0 Chassis Fabrication $100.0 Chassis Fabrication $100.0 Fasteners $20.0 Fasteners $20.0 Frame Total $420.0 Frame Total $420.0 Armor/Defense (Dave Bailey) Armor/Defense (Dave Bailey) Armor Material $8,000.0 Armor Material N/A Fasteners $30.0 Fasteners $30.0 Titanium (36"x24") $197.1 Titanium (36"x24") $197.1 Armor/Defense Total $8,227.1 Armor/Defense Total $227.1 Misc. Misc. Electrical wiring (Power System Wiring, Electrical wiring (Power System Wiring, switches and terminals) $150.0 s witches a nd terminals) $150.0 Misc. Tota l $150.0 Misc. Total $150.0 Total Robot Cost $16,268.1 Total Robot Cost $8,088.1 Total Project Cost $19,858.1 To Date Received Cash Donation as of 11/12 $9,100.0 Total "Out of Pocket" Project Cost $0.0

Appendix D1

APPENDIX E – PROJECT SPONSORSHIP

Company Donation Amount Donation Received? Avenue Fabricating cash $4,000.00 Yes Makino cash $2,500.00 Yes RA Jones cash $2,000.00 Yes Duke Energy cash $500.00 Yes F & M Mafco cash $100.00 Yes Titanium Honeycomb armor and Aeronca Inc. N/A Yes other sheet material UGS Solid Edge Version 20 N/A Yes Meritor Webco Tools and miscellaneous equipment. N/A Yes UGS/Engineering Methods Solid Edge Training Yes Solid Works EDU Solid Works and Cosmos Software N/A Yes Will cover complete competition and University of Cincinnati travel expenses including but not Mechanical Engineering $4,000.00 No limited to hotel, entry fee, and Technology Department transportation costs. Tische Enviromental cash $500.00 No Total Cash Donation: $13,600.00

Sponsor Pledge Statement Jake Barnhorst,

This email is to confirm that the MET Department will cover the expenses of the team trip to Miami for the National University of Cincinnati Mechanical Engineering Technology Department Competition.

Good Luck! Muthar Al-Ubaidi Department Head

Jonathan Taphorn,

Please use this email as a commitment on behalf of Tisch Environmental to sponsor the University of Cincinnati CAS effort to compete in BattleBot competition in the amount of $500. Please provide date, payee and mailing address for the donation.

Tisch Environmental Thanks, John Tisch

Appendix E1

APPENDIX F – SCHEDULE

Q ua rter Fall Quarter Winter Break Winter Quarter Week Number 8 9 10 Exams 1 2 3 4 1 2

Dates 1/6-1/12 12/2-12/8 1/13-1/19 11/25-12/1 12/30 - 1/5 11/10-11/17 11/18-11/24 12/15 - 12/9 12/23-12/29 12/16 - 12/22 Task Brainstorming to meet requirements of "Hows" 10-Nov Engineering Characteristics "Hows" Completed 11-Nov Survey Results analyzed ; QFD completed 12-Nov preliminary Design Calculations (all components) 13-Nov 25-Nov proof of design statement 30-Nov meet with professor Caldwell about weapon 5-Dec calculations - make assumptions about forces finalize all main weapon calculations: spin up time, force delivered, required weld thicknesses, rotor diameter, 6-Dec 12-Dec and V-belt selection design of weapon completed 13-Dec Design Freeze 14-Dec send drawings out to machine shop for drum body, 14-Dec drum rotors, and drum teeth Machining of Drum Body, drum rotors, and drum teeth 15-Dec 15-Jan

Appendix F1

Q ua rter Winter Break Winter Qua rter Week Number 2 3 4 1 2 3 4 5 6

Dates

2/3-2/9 1/6-1/12 1/27-2/2 1/13-1/19 1/20-1/26 2/10-2/16 12/30 - 1/5 12/23-12/29 12/16 - 12/22 12/16 O rder main wea pon motor, V-Belts ,a nd ba tteries for 16-Dec testing receive main weapon motors and batteries 23-Dec testing of main weapon motors and batteries for amp 24-Dec 12-Jan draw and battery design Get drum body, drum rotors, and drum teeth back from 16-Jan machine shop Welding of Main Weapon drum body, drum rotors, and 17-Jan 28-Jan drum teeth send out main weapon assembly and backup assembly 29-Jan for high speed balancing get main weapon assembly back from high speed 5-Feb balancing Assemble and install main weapon into body of 9-Feb BattleBot Order main weapon motor back-up, battery back-ups, and V-Belt back ups 12-Feb Order all common "shelf" parts (fasteners) 17-Dec 5-Jan

Appendix F2

Q ua rter Winter Qua rter S. Brea k Spring Quarter Week Number 3 4 5 6 7 8 9 10 Exams 1 1 2 3 4 5 6 7 8 9 10

Dates 2/3-2/9 3/2-3/8 6/1-6/7 1/27-2/2 2/24-3/1 3/9-3/15 3/30-4/5 4/6-4/12 4/27-5/3 5/4-5/10 5/25-5-31 1/20-1/26 2/10-2/16 2/17-2/23 3/16-3/22 3/23-3/29 4/13-4/19 4/20-4/26 5/11-5/17 5/18-5/24 a ssembly of robot 25-Jan 29-Feb testing/troubleshooting/competition practice 1-Mar 26-Apr oral design presentation 14-Mar design report due 14-Mar drive to competion 29-Apr BotsIQ National Competition Miami Beach, FL 30-Apr 4-May drive home from competition 5-May cons truct tech expo display 7-May 21-May tech expo 22-May Final Oral Presentation 30-May Final Project Due 30-May

Appendix F3

APPENDIX G – SAMPLE CALCULATIONS

Assumptions for Weapon: • Main weapon drum calculations will be analyzed as a “flywheel” from Machinery’s Handbook, Applied Strength of Materials – Mott, and Machine Element in Mechanical Design - Mott • 80% of theoretical max torque will be applied during start up • 15 degree contact angle of tooth while delivering blow to opponent • Only 50% of total available energy by the drum will be delivered to opponent

Weapon Geometry Calculations 1 Polar Moment of Inertia − Drum Body J = m(r 2 + R2 ) m 2 1 J = .469slugs ×(.1042 ft +.1252 ft)' m 2 2 J m drumbody =.006lbs − ft − sec

1 Polar Moment of Inertia − Drum Rotors (2) − J = mR2 m 2 1 J = .037slugs ×.1252 × 2 rotors m 2 2 J m drum rotors =.0006lbs − ft − sec

2 TotalWeapon Polar Moment of Inertia, J m =.007lbs − ft − sec

Drum Speed, Torque, and spin up time Calculations: Motor HP = 4.5 Motor output speed = 4500rpm

Diameter of motor sheave= 2.5inch = .21ft Diameter of drum = 3inch = .25 ft

Appendix G1

motor speed Drum(weapon) resul tan t speed = drum diameter motor sheavediamter 4500rpm Drum(weapon) resul tan t speed = .25 ft .21ft Drum(weapon) resul tan t speed = 3750rpm = 392.7 rad / sec Drum(weapon) resul tan t torque = 23.25 ft − lbs

Assume80%of torque applied at start up = 18.6 ft − lbstorque J (ω − ω ) Drum Spinuptime = m f o To .007lbs − ft − sec 2 (392.7rad / sec− 0rad / sec) Drum Spinuptime = 18.6 ft − lbs Drum Spinuptime =.141sec

Energy from weapon and force calculations.

Mean Radius must be found for drum radius and outsidetooth radius. 1.5in + 2.25 r = =1.875 ≅ 1.9in→ .16 ft mean 2

2×π × R× n velocity at "rim = 60 2×π ×.16 ft ×3750rpm velocity rim 60

velocityrim = 62.18 ft / sec

Appendix G2

W × v 2 Total energy available by weapon, E = 2g 1 → Note : equationtaken from Machinerys Handbook. Compared with E = Iω 2 .Re sults came within 2% 2 thereforeoriginal assumptions and figures canbeused.

Weight of drum(spinning mass) = 17lbs Teethcontact angle = 15deg rees Length of contact arc (arclengthequation@15 and 1.5in radius) =.041ft W × v 2 Total energy delivered by weaponif at full speed and brought to stop suddenly = 2g 17lbs× 62.182 E = 2× 32.2 Total Available Energy =1021.8 ft − lb

E Force Delievered by sin gletooth = dis tan ce 1021.8 ft − lb Force = .041ft Force = 24,655lbs

Assumeonly 50%of force will be delivered during competition dueto deflection and reaction.

Force Actual = 24,655lbs× 50% =12,328lbs

Bending Stress on drum body Drum Length (in) 17.25 Drum Outer Diameter (inch) 3 Drum Inner Diameter (inch) 2.5 Drum Material Ultimate Strength (psi) 100000 Design Safety Factor for Dynamic Loading (Visodic model) 5 Design Max Stress not to exceed (psi) 20000

Appendix G3

π (D 4 − d 4 ) S drum = 32D π (34 − 2.54 ) S = drum 32× 3

= 4 S drum 1.37in PL Max Bending Moment = for evenlysup ported beams 8

× 12328lbs 17.25inch M max 8

M max = 26,581in − lbs

M σ = max max S

26,581in − lbs σ max = 1.37

σ max = 19,369 psi

Allowable Stress = 20,000 psi → SAFE

Individual Tooth Stress

Tooth Stress Tooth Material ultimate strength 100,000psi Tooth Height 0.75in Tooth Length 1.717in Tooth Width 0.5in Weld Bead width .25in Weld bead width corrected (multiply by .707) .177in Weld bead total area .6069in^2

F × D σ = tooth A 12,328×.75in σ = tooth .6069in 2

σ tooth = 15,233psi Allowable = 20,000 psi → Safe

Appendix G4

Rotor Step stress concentration PL M = bearing A 8 6164lbs ×8in M = bearing A 8

M bearing A = 6164in − lbs

D 3 = = 2 d 1.5 r .375 = = .25 d 1.5

kt = 1.355

M σ = × k no min al πd 3 t 32 6164 σ = ×1.355 no min al π1.53 32 σ = ↓ no min al 25,207 psi This is greater than the allowable stress but the welded teeth will act as ribs providing greater strength to the drum. This is impossible to calculate but it will be assumed that the stress will be less and the geometry will be sufficient.

Key Design (Long shaft) 1 1 stadard key size (long shaft side) − × 8 8 key material ultimate strength − 51,000 psi

Pulley MaterialUltimate Strength, S y − 51,000 psi Torque from motor,T = 232.5in − lbs Key Design Factor , N = 3 Motor shaft Diamter, D = .5in width of key contact ,W = .125in

4TN Minimum required keylength = DWS y 4× 232.5×3 Minimum required keylength = .5×.125 Minimum required keylength = .875

Appendix G5

Key Design (short shaft) 3 3 stadard key size (short shaft side) − × 16 16 key material ultimate strength − 51,000 psi

Pulley MaterialUltimate Strength, S y − 51,000 psi Torque from motor,T = 232.5in − lbs Key Design Factor , N = 3 Motor shaft Diamter, D = .5in width of key contact ,W = .1875in

4TN Minimum required keylength = DWS y 4× 232.5× 3 Minimum required keylength = .5×.1875 Minimum required keylength = .584 ≅ .6

Battery Selection for motor Results from Motor test using Ammeter and weapon simulator. • Motor startup – 160A for 1 sec • At speed – 50A

Assumptions: weapon will be stopped due to attack or direction change 20 times within a 3 minute match. • 160A x 1 second duration x 20startups/match = 3200A-s o 180sec (3min) – (20startups x 1 sec) = 160 seconds • 160 seconds x 50 amps at speed = 8000A-s

-3.2 A-h battery = (3.2 x 3600secs) = 11,520 A-s available from 1 battery -8000 A-s + 3200 A-s = 11,200 A-s 11,200 A-s < 11,520 - Theoretically one 3.2 A-h battery will last one match but power will not be sufficient during end of match. Therefore two 3.2 A-h batteries will be used.

Appendix G6

APPENDIX H – CUSTOM PART DRAWINGS

Main BattleBot Assembly

Appendix H1

Main weapon Assembly

Appendix H2

Main Weapon Body

Appendix H3

End Caps/Rotors

Appendix H4

Weapon Teeth

Appendix H5

Main weapon Motor Mounts (Assembled)

Appendix H6

APPENDIX I – STANDARD PARTS DESCRIPTION

Main weapon Motor (1)

Manufacturer: Magmotor Vendor: The Robot Marketplace

3" Diameter, 6.7" long 1/2" diameter shaft with 1/8" keyway, 1.75" long 24V (can be run higher) 4.5 horsepower 3720 oz-in Torque Max current 390 Amps 83% Efficiency 4900 rpm 6.9 lbs Neodymium magnets

Price: $360

Appendix I1

Main Weapon Motor Batteries (2)

Manufacturer: Battle Pack Vendor: The Robot Marketplace

24V Sub-C cells (x20) 60 amp continuous 4.528W x 1.901H x 3.622D (without rings) 5.153W x 1.901H x 4.122D (with rings) 2.64 lbs

Price: $147/pack

Appendix I2

Main Weapon Motor Pulleys (2)

Manufacturer: Gates Vendor: Kaman Industrial Technologies

Solid Type, Machined Turned Steel Pulley 2.5” OD ½” bore 4L section belts

Price: $11/pulley

Appendix I3

V-Belts (2)

Manufacturer: Dayton Vendor: Grainger

V-belt 4L cross section 24 inch length Cogged style

Price: $10/belt

Appendix I4

Weapon Bearings (2)

Manufacturer: McMaster-Carr Vendor: McMaster-Carr

Part Number: 6381K314 Material Bronze Bronze Type Alloy 932 (SAE 660) Bronze Type Sleeve Bearings For Shaft Diameter 1-1/2" Outside Diameter 2" Length 4" Load (P Max) 4000 Speed (V Max) 750 Load at Speed (PV Max) 75000

Price: $22 for 4 inch length

Appendix I5

APPENDIX J – MAIN WEAPON WIRING SCHEMATIC

- +

(2) 24V 3.3A-h Wired in parallel totaling 6.6 A-h @ 24V

- +

Master Power Switch – 300A continuous, 1000A peak

- +

IFI Victor 885 Speed Control 90 A continuous, 200A for 2 sec, 300A for 1 sec

- + M 24V 4.5HP

Appendix J1