 Consultant ◦ Mike Zona (Xerox)  Sponsor ◦ Dr. Lamkin-Kennard Chris Anderson, Jon Gibson, Kurt Stratton, Josh Koelle

 Project Recap/Proposed Design  System Connections & Interactions  McKibben Air Muscle Testing  Air Supply Selection  Power Supply Selection  Logic Selection & Implementation  Shell/Covering Design: Aesthetics  CAD Model  Model Analysis  Bill of Materials  Risk Assessment  Updated Engineering Specs  Test Plan  MSDII Schedule

 The mission of the Robo Ant team is to design and build a biomimetic ant capable of forward movement via a self-contained air muscle system.  This Ant will need to utilize the McKibben Air Muscle technology.  Documentation is also extremely important for future project progression and use of Robot.

 Completely Self Contained Robotic Ant. ◦ Air Supply, Power Supply, Controls, & Muscles will all be on-board.  Utilizes McKibben Air Muscles to move forward, backward, and turn.  Touch Sensor Controlled, using an Arduino Board.  Rechargeable Power & Air Supply.

Battery Power Runs Arduino & Solenoids Air Tank releases Air into Solenoids and Muscles Compressed Air is Converted to Motion McKibben Air Muscles and Cables Moves Each Leg Mechanism Leg Mechanisms (6) Move in Specific Pattern Programmed Arduino Board Sends a Digital Output Output Causes A Specific Change in the Solenoid Valves Ant Moves Forward Power & Air System Control System Mechanical System

 Used research done by previous Senior Design teams and Grad Assistant Sylvan Hemmingway.  Chose muscle specifications to closely examine: ◦ Lengths of 4” and 6.5” ◦ OD 3/8”, 1/4” ID. ◦ Tested at 60 psi. arms-biorobotics.html

*Tests were done at 60 psi

 Based on the calculations for the lifting power required by the air muscles, and the results of previous projects, we built and tested air muscles of two different sizes: approximately 4” & 6in” with outside diameters of 3/8” and inside diameters of 1/4”. ◦ Previous research showed that we should be able to see deflections lengths and lifting power near what we will need for the design of this project using this size muscle at 60 psi.

 Options we considered: ◦ Mini Air Compressor ◦ Mini Air Compressor with Tank ◦ Air Tank (Paintball)  What we have selected for our design: ◦ Paintball Air Tank  At 3 lbs and 3000 psi this tank is a lightweight an option that is affordable and will provide a long lasting supply of air.  Can be reduced down to 60 psi via a regulator.

 Will use the Solenoids from “Monster Hand”  24 VDC, 3-way Solenoids  Most cost effective (can be salvaged from “M.H.”)  Tested a few solenoids to get an average amperage draw: Solenoids Tests Solenoid #Voltage (V)Current Draw (mA)

 Assumptions: ◦ 24V Solenoid ◦ 2000 mAh Battery ◦ 18 total Solenoids (6 per leg)

 Options we considered: ◦ Lead-acid batteries ◦ Tethered power supply ◦ Nickel-metal Hydride  What we are planning to use: ◦ 24V 2000mAh NiMH Battery w/ Bare Leads  Lightweight (1.15 lbs)  Has enough power to run 24V Solenoids for ~7,400 steps  Affordable

 Options we considered: ◦ Labview Control ◦ Arduino Microcontroller ◦ Wireless Control  What we are planning to use: ◦ Arduino Mega 2560  Simple programming language  54 channel capability  Fully autonomous

 Options we considered: ◦ Pushbutton switches ◦ Sonar Sensor ◦ IR sensor  What we are planning to use: ◦ Pushbutton switches  Simple mechanical design  Easy to implement  Low power draw

 Options we considered: ◦ Solid State Relays ◦ Electromechanical Relays ◦ PC Board  What we are planning to use: ◦ Electromechanical Relays ◦ PC Board ◦ Transistors

Ant Locomotion  Tripod Layout  Ant Cadence html Real-time control of walking By Marc D. Donner

Ant Locomotion – Turning html  2 and 1 Layout  Ant Cadence

Start Define variables and pin configurations Reset leg positions Run Take half step Check bump sensors Stop Program will run continuously until loss of power or activation of kill switch

 Using Plexiglas or Lexan, we can Heat Form or Cold Form a basic shell. ◦ Plexiglas can be bent fairly easily into almost any desired shape. A heat gun allows for more precise and long lasting forms. ◦ Cheap method for creating a shell, using leftover Plexiglas from previous projects. ◦ Can be done by free-hand or using a simple mold.

 Design uses two layers for maximum space Muscle Bank 1 “Forward” Rotation Muscle Bank 2 “Backward” Rotation Muscle Bank 3 Leg Lifting Controls Section Air Tank Battery Solenoids and Manifolds

 As presented previously, we are using a 2- DOF leg. Fspring Fmuscle (lift) Fmuscle (rotate) Bronze Bushing 3/8” Shaft Shoulder Bolt

 Modeled in ANSYS  Full Loading  Yield Stress 20,000 psi

RiskEffectCause Likelih ood Seve rity Import ance Action to Mitigate/CorrectBack-Up Plan Muscles expansion is limited by the other components contained in the ant (assuming a goal of total self-containment). Required force to control the ants movement is not met. Not enough displacement Internal components are packed too close together, not allowing for the muscles to expand Make sure the muscles have enough space to expand and move, with limited contact to other components of the ant. Redesign the layout of the internal components of the ant so the muscles fit. Leg Functionality The legs are not able to pull the ant forward. The legs might not be strong enough or have enough friction with the ground to create forward movement Using a strong material for the legs and possibly placing a rubber mat under each leg to increase the friction between the legs and the ground. Reinforce the legs so they can support the weight. Find a stickier base for the legs so they grip the floor better. Leg Movement Design Flexion and Extension of the muscles do not create forward movement, due to the mechanics of the legs being poorly designed. Improper mechanical design of the legs The design must be carefully analyzed and tested before committing to a final decision, making sure the designed movement of the legs will create forward motion. The only back-up plan for this is redesign the legs. Proper testing should help prevent this risk Air Supply Not enough available air will prevent the muscles from expanding, and in turn, preventing consistent movement. The air supply provided cannot keep up with the demand of air that the muscles require Double-check required air flow calculations to make sure proper Air Supply is included in the design. A backup plan will allow for an outside air source, such as an air pump, to be connected to the ant. Solenoids Not Functioning Properly The air muscles do not receive or discharge the proper amount of air, causing inconsistent movements. The Solenoids are not functioning correctly, not allowing enough air to enter the muscles and/or not allowing the air to be released. This could be due to a bad Solenoid, since many are used or have not been functioning in a long time Test all Solenoids before assembly of the ant. Also have extras that have been tested, in case a replacement needs to be made.

McKibben Air Muscle Structure Muscles cannot expand fully, causing inconsistent movement with the ant's legs. Muscles could be poorly assembled, with leaks or tears Carefully assemble each McKibben muscle, making sure all connections are tight. Make extra muscles, in case a quick switch needs to occur. Muscles Do not Move Consistently The Ant does not move in a fluid motion, causing a divergence from straight line, making it difficult to correct while in motion. Trying to reach equal deflections in all of the muscles can be very difficult, and as such it can cause inconsistent movements in the leg. The movement of the Ant weighs heavily on the movement of the legs, which need to move the same distance every time To prevent this from happening, mechanical stops will be added to the design that will stop the legs from moving too far. The muscles will be pressurized just over the required amount to move the legs to the stop. This will ensure the legs are moving a consistent distance every time. Mechanical stops can be moved or thickened to fine tune the leg movement. Poor Traction with "Feet" and Ground The legs can just slide back and forth on the ground, not providing the proper movement. The muscles are filled with air so rapidly that it will cause the legs to move or "snap" quickly forward/backward/up, which can cause the ant to slide along the ground rather than provide the correct/instructed movements Add pads of some sort to increase the amount of traction between the feet of the Ant and the ground. Add needle valves to restrict the flow and cause more fluid motions. Leg movement "pinch" that induces slip. This can cause the feet to slip outwards or cause high stresses in ant body. This could be caused by the leg springs not accommodating the vertical movement of the ant body Account for body movement when designing leg for the springs. Redesign leg structure to allow for deflection in outward direction. Communication with Logic The Arduino Board does not communicate correctly with the ant, creating improper movement. Careless design of logic or possibly bad connections with the ant and the motion sensors Consistently test the logic with the ants movements. Allow for weeks of complete testing to work out all bugs and ensure proper logic- to-mechanics functions. Make sure the motion sensors are properly functioning. Reflash the Arduino board with working logic.

Power Supply The power supply does not generate enough power to run all necessary components, preventing any movement of the ant. Not enough power is generated from the on board power supply Make sure batteries are fully charged and functioning for each test. As a backup plan, a tethered power source will be able to connect to the Ant. Poor Documentation Dissatisfied Customer. Future groups can't work off of results. Poor documentation throughout design process Documentation needs to be kept current through the process. If we get behind on documentation it will be difficult to catch up. The group needs to keep up with documentation every week. Mismanaged Budget Team is handicapped by limited resources. Diverge from initial concept development plans. Solutions to project where improperly forecasted from a fiscal standpoint. Are solutions in the realm of realistic funding? 6954 Forecast solutions from a fiscal standpoint. Forecasting should occur at the end of concept development phase.

Functional Module Name Engineering Specifcation Number Engineering Specifcation Description Measure of Performance Preferred Direction Marginal Value Ideal Value Movement a.1Ant Speedft/sUp0.662 a.2Turning RadiusftDown-2 a.3Deviation from Straightin/ftDown20 a.4Operation RangeftUp2050 a.5Muscle Operating PressurepsiTarget-60 a.6Muscle LiftinglbUp2830 a.7Muscle LengthinTarget64.5 Controls b.1Air CapacitygalUp-10 b.2Air Tank RuntimeStepsUp75200 b.3Recharge TimeminsDown 180 b.4 Minimal Number of Control Inputs#Down-3 b.5Air PressurepsiTarget-60 b.6Unit Power SupplyVTarget-24 b.7Number of Air Lines#Target-18 b.8Length of TetherftDpwn-0 Body c.1Weight of UnitlbDown20 c.2Unit LifecyclesUp c.3Number of Body Sections#Target33 c.4LengthinTarget42- c.5WidthinTarget18- c.6HeightinTarget9- Documentation d.1Usage Instructionyes/noTargetyes- d.2 Manufacturing/Mechanical drawings and instructions yes/noTargetyes-

 We will be testing the following items: ◦ Muscle Operating Pressure ◦ Muscle Lifting Capability ◦ Air Tank Pressure Output ◦ Air Tank Runtime ◦ Solenoid Functionality & Current Draw ◦ Power Supply Voltage ◦ Controls Operation Consistency ◦ Leg Movement & Robustness ◦ “Kill Switch” Capabilities

MSD1&2 - P12029: RoboAnt Week 1Week 2Week 3Week 4Week 5Week 6Week 7Week 8Week 9Week 10Week 11 SuMTWThFSSuMTWThFSSuMTWThFSSuMTWThFSSuMTWThFSSuMTWThFSSuMTWThFSSuMTWThFSSuMTWThFSSuMTWThFSSuMTWThFS Meet With Customer Assess Risks & Mitigation Peer Review for Group Members Update Project Plan Upload Documents to EDGE Reevaluate System Design Inventory/Organize Old Parts Choose Leg Movement Mechanism Choose Air Supply Select Power Supply Workout Logic Ideas Work on Detailed Design Design Back-up Plans Bill of Materials Estimation Create Solidworks Models Prepare Project Management Review Project Management Review Order Parts for Project Inventory/Check All Parts Received Create Logic Mill Desired Parts Assemble Air Muscles Test Air Muscles Assemble Mechanical Components (Legs) Assemble Air System and Power Test Each System Together Test For Failures Combine All Systems onto Ant (Build) Implement Back-ups if Needed Test Logic With RoboAnt Run Ant Without Problems Documentation of Tests/Assembly/Etc. Final Technical Paper RoboAnt Poster Completion of MSDII

Thank you for your time and support.