Detailed Design Review 3/4/2013 Mike Walsh Nick Davis Charles Kowalyshyn Zeb Koch

- Project Introduction - Review of Customer Needs - CAD Model and Subsystem Analysis - Calculations - System Interfaces - Schematics - BOM - Risk Assessment

 Tasked with creating a device to: ◦ Move a disabled jib trimmer on a Sonar Sailboat from Port to Starboard

 Gary & Zak ◦ No leg mobility / core support ◦ Desires to be fully secured  Cindy ◦ Partial leg & core strength ◦ Desires freedom to exit seat when necessary ◦ Limited footprint available due to P13032’s chair  Cindy needs the option to sail with Gold Medal Chair or as a standalone device  Height differences to consider

 Multipurpose Aluminum (Alloy 6061) Rectangular Tube

 Assume concentrated load for weight of Seat Bracket at “X” (Center of Gravity)  Free Body Diagram: ByBy TxTx TyTy BxBx W seat M

Sum the Forces and Moments  ΣF x = 0 = T x + B x  ΣF y = 0 = T y + B y – W s – W p  ΣM = 0 = M – T x Y t –T y X b – W s (X ws -X b )- W p (X wp - X b )  3 equations  4 unknowns  M max =131 ft-lb ByBy TxTx TyTy BxBx WsWs WpWp M Y wp Y ws XbXb X ws X wp YtYt

 Simulated the bracket as a cantilevered beam  Used Superposition of Table A9 in Shigley’s  Relating T y to B y, W s, W p  Sum of deflections due to forces at B = 0 W person W seat BxBx TyTy TxTx M ByBy YtYt XbXb X ws X wp

Solves the four equations, with M=131 ft-lb  >> JTB2()  Top Bar X-Force: lbs  Top Bar Y-Force: lbs  Bottom Bar X-Force: lbs  Bottom Bar Y-Force: lbs  Top Bar Total Force: lbs  Bottom Bar Total Force: lbs  Top Bar Deflection: inches  Max Yield Stress : psi  Top Bar Max Stress : psi  Pass!-Top Bar  The Stress Factor of Safety is

 Maximum Deflection when seat is at center position  Stainless Steel – 1” Diameter  δ max = FL 3 /(48EI) where I = πr 4 /4  F max =4σπ/DL R1R1 R2R2 Net Forc e Top Traveler Bar

 The stresses in the Seat Bracket are very small.  Second moment of inertia is very large ◦ Large C-S area ◦ Assume two beams and check stress in both σ= My/I I=1/12 * b * h3 b= 6.5 inches h=.5 inches y=.25 inches YtYt X wp TxTx WpWp

Seat Bracket- Back  Max Yield Stress : psi Seat Bracket- Bottom  Max Yield Stress : psi

 Generated a list identifying: ◦ All major components ◦ How they interact with one another  (i.e. “foot-bone connected to the leg-bone”) ◦ Possible critical Loads

System Interfaces Component 1Component 2How does it interface Is there a critical load at this interface? Parts associated with interface Boat handholdHandhold MechanismFriction forceMomentHandhold Mechanism Rail fastening. Bolts connect the bearing to Handhold MechanismNo Aluminum slot framing, bearing, hand brake Rail Bottom RailBolts to Bottom RailNoBolts, Nuts, Rail, Bottom Rail OR L-BracketFastens to L-BracketNoBolts, Nuts, Rail, L-Bracket Rubber Seat PadL-BracketAdhesiveNo Rubber Seat Block, L-Bracket, Bolts Rubber Seat PadSeat of BoatFriction forceNoRubber Seat Pad L-BracketBottom Rail Bottom rail goes through L BracketNo L-Bracket, Bolt, Bottom Rail,Weld L-BracketTop BarFlangeYes L-Bracket, Top Bar, Flange/Base Mount

Component 1Component 2 How does it interface Is there a critical load at this interface? Parts associated with interface Top BarTop Bar Bearing BlockBearingNo Top Bar, Top Bar Bearing Block Top Bar BearingSeat BracketBoltsNo Top Bar Bearing, Seat Bracket, Bolts Bottom RailBottom Rail Bearing BlockBearingNo Bottom Rail, Bottom Rail Bearing Block Bottom Rail BearingSeat BracketBoltsNo Bottom Rail Bearing, Seat Bracket, Bolts Seat BracketLazy SusanBoltsNo Seat Bracket, Lazy Susan, Bolts Lazy SusanChairBoltsMaybe, MomentLazy Susan, Chair, Bolts ChairHarnessBoltsNoChair, Harness, Bolt Bottom RailSupport PostRail-Post interfaceNo Bottom Rail, Support Post, 2 Quick Pins, Aluminum Square Tube Support PostBaseplateBoltsNo Support Post, Baseplate, Bolts BaseplateBottom of Boat Plate clamp, hooks in cabNo Baseplate, Boat, Plate clamp, hooks

Component 1Component 2 How does it interface Is there a critical load at this interface? Parts associated with interface Seat BracketPad-Eye (on Seat Bracket)BoltsNo Seat Bracket, Pad-eye, screw Pad-Eye (on Seat Bracket)Purchase System BlocksSchackleNoPad-eye, blocks, shackle Purchase System BlocksPurchase System Line Block - Line InterfaceNoBlock, Line Side BracketPad-Eye (on Side Bracket)BoltsNo Seat Bracket, Pad-eye, screw Pad-Eye (on Side Bracket)Purchase System BlocksSchackleNoPad-eye, blocks, shackle Purchase System BlocksPurchase System Line Block - Line InterfaceNoBlock, Line Rotational Locking MechanismChairUndeterminedNo Rotational Lock, Chair, Mystery Machine Translation Locking MechanismCleatsUndeterminedNoTranslational Lock, Cleats

 3-1 Purchase System Breakdown Seat Bracket PortStarboard Lines wrap around to center position

Refer to BOM + Budget doc

 Zak & Gary ◦ Searched dozens of bucket seats ◦ Size and corrosion requirements constrained selection ◦ Settled on RCI High-Back Aluminum Racing Seat with vinyl cover ◦ Relatively cheap  Cindy ◦ Constrained with footprint due to P13032’s chair ◦ Did not find suitable stool on the market ◦ Currently looking into stadium seats

 1. Budget  2. Interfacing with other team’s base plate  3. Brake – Rotational motion  4. Handhold Design  5. Inability to accept user’s cushion due to size constraints

 Projected:$2,  Cindy’s System:$2,  Zak and Gary’s System:$2,  Not included: ◦ Shipping costs ◦ Machining of aluminum plates ◦ Corrosion testing ◦ Delivery to customer

 Purchase System: $  6061 Aluminum: $ ◦ 47% of Budget  Metals (tubes, plates) ◦ BOM has from internet suppliers’ numbers ◦ Looking locally to reduce shipping and price - Klein Steel

 For use with P13032’s Captain’s Chair, the design changes: ◦ Repeated bolt pattern in P13032’s base plate ◦ Less handholds are available ◦ Need Installation procedure when used together

 Currently, the brake for the Lazy Susan is undefined.  Working on several ideas Friction PlateForce-Action Clamp Ratchet & Pawl

 Curved rubber wedge into Lazy Susan turntable

 Working to improve the previous team’s solution  Working hand-in-hand (hold) with group P13032 to design a standard handhold