Detailed Design Review

Transcription

1 Detailed Design Review Tethered Glider P14462

2 Outline Engineering Requirements Glider Status Tether Design Base Station Design DAQ System Bill of Materials DOE ANOVA Analysis Test Plan MSD II Plan Work Breakdown Risk Assessment

3 Engineering Requirements

4 Glider Status Art s Plane o o Suffered Multiple Crashes Totalled 1 st Bixler o o Few flights on first day Missing in swamp 2 nd Bixler o On order

5 1 st Bixler Learned how to glue glider and set up receiver Needed to be modified due to poor manufacturing o Drilled out interfering plastic/wood Bixler was tail heavy

6 Tether Design DynaGlide Throw Line o o o o o o Material: Dyneema with Vinyl Coating Vendor: WesSpur Diameter: 1.8mm Tensile Strength: 1000 lb Highly Visible Price: $39.00 for 200 feet 12/10/

7 Tether Drag Numerical Approximation Calculates: o o o Tether Drag Tension Change Tether Angle Change Rajani, Ashok, Rajkumar Pant, and K. Sudhakar. "Dynamic Stability Analysis of a Tethered Aerostat." Journal of Aircraft 47.5 (2010): American Institute of Aeronautics and Astronautics. Web. 7 Dec <

8 Tether Drag Total tether drag of DynaGlide tether: N Negligible force compared to the lift and drag

9 Tether-Wing Attachment Setup

10 Tether-Wing Attachment Tether may rip EPO foam if attached directly Design plate to rest on top of wing o o Distributes load Foam is minimally damaged Tethered over carbon fiber spars Material: Polycarbonate

11 Tether-Wing Attachment Setup

12 Tether-Wing Attachment Stress Analysis Plate material: Polycarbonate Max stress: 38.4 GPa Max allowable: 55 GPa

13 Tether-Wing Attachment Displacement Analysis Plate material: Polycarbonate Max deflection: in

14 Bridle Setup 3 point bridle with extra support line Use crimps for permanent attachments Adjustable fuselage tether to change bridle angle

15 Bridle Setup

16 Base Station - Week 6 Concept Concept from week 6, selected by week 9 Consists of 2 potentiometers and 1 load cell

17 Base Station - Detailed Design

18 Base Station - Detailed Design

19 Exploded View of Upper Portion

20 Design Focus - Upper Portion Wanted minimal flexing on the shaft in order to prevent bearing seizure Wanted to prevent screw pullout Wanted minimal plywood flexing Ensure top bolt did not tear through plywood due to loading

21 Shaft Selection y x T=1200 lbf R L =600 lbf R R =600 lbf Wanted to minimize deflection, bending stress, and moment of inertia of shaft Utilized Excel and varied L and R and calculated corresponding deflections and max stress

22 Shaft Selection Continued Selection: ¾ x 7 AISI 1566 Steel shaft Only 4 of the shaft will be between the bearings, which is the length used for deflection and stress calculations. With these values the shaft will deflect under the max loading of 1200 lbs The thicker shaft allows for tapping in order to connect the load cell

23 Pillow Block Screw Pullout y T=300 lbf x Selection: 4 #12-10 machine screws ¾ C-D grade plywood dia/technicaldata/452.pdf

24 Plywood Flexing Modeled as an isotropic material, although wood is anisotropic Showed max deflection of 0.503E-05 inches

25 Bolt Tear Through Wanted to prevent the bolt from tearing through the plywood A 3 inch washer was added to distribute the loading on the face of the plywood Without Washer: Compressive stress on the plywood of 8692 psi. The maximum allowable compressive stress for loading perpendicular to the face grain is between ~ psi With Washer: Compressive stress on plywood of 170 psi, within the allowable stress 1200 lbf 8692 psi 1200 lbf 170 psi Source:

26 Pillow Block Bearings Shaft will insert and then be screwed down with set screws Do not need to be thrust bearings, as platform will rotate Selection: ¾ Stamped-Steel Mounted Ball Bearings ABEC-1

27 Exploded View of Lower Portion

28 Design Focus - Lower Portion Wanted to ensure sleeve bearing did not deform under worst-case scenario loading Wanted to prevent screw pullout Ensure sheet metal flexed minimally under applied load

29 Sleeve Bearing T=1200 lbf H Selection: R L R R h s b Utilized Excel to calculate various reaction forces for different h sb, and compared versus the max allowable force on the inner walls of the bearing For worst case scenario chosen bearing will see 5100 lbs and it is capable of handling 6016 lbs x 1 Ultra Tough Oil Lubricated Bronze Flanged Sleeve Bearing

30 Angle Iron Pullout and Shear F=300 lbf F=200 lbf Selection: 1 x1 x1/8 angle iron with #12 screws F=300 lbf 6 vertical screws, and 4 horizontal ¾ C-D grade plywood dia/technicaldata/452.pdf

31 Sheet Metal Plate Max deflection of ~ inches

32 Base Station Cross Section View

33 Base Station Animation Base Station Animation

34 NI USB bit Resolution = 10/(2^16) =

35 3140_0 S Type Load Cell ( kg)

36 1046_0 PhidgetBridge 4-Input Resolution = 5/(2^24) =

37 Potentiometers 2 pots required. 1 turn ~ 270 degrees Between 1K-10K Resistance Linear Bourns brand Potentiometers from Gomes still need to be spec out

38 DAQ Operational Flowchart

39 DAQ Programming Flowchart

40 Wiring Schematic for DAQ

41 Bill of Materials - Full

42 Bill of Materials Already Have

43 Bill of Materials Need to Buy

44 Bill of Materials - Possible Savings

45 Glider Configuration for Experiments Total configurations: 2590 Range: Beta = [deg] Wind Speed = 4-10 [m/s] Tether Length = [m] Flight Radius = [m] Filtered: Force = [lbs] Wind Speed = 7 [m/s] Tether Length = 30 [m] Force [lbs] Wind Speed [m/s] Radius [m] Beta [deg] Tether Length [m]

46 Regression Analysis including Wind Force = WindSpeed Radius Beta TethLen Analysis of Variance Source DF Seq SS F P Regression WindSpeed Radius Beta TethLen Error Total

47 Why the high error? Residual Plots for Force Normal Probability Plot Versus Fits Percent Residual Residual Fitted Value Histogram 200 Versus Order Frequency Residual Residual Observation Order

48 DOE ANOVA Analysis Analysis is based off of above equation Experiment was run using the following Factor Type Levels Values Radius fixed 9 10, 11, 12, 13, 14, 15, 16, 17, 18 Beta fixed 8 91, 92, 93, 94, 95, 96, 97, 98 TethLen fixed 11 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 Analysis of Variance for Force for Tests Source Seq SS Radius Beta TethLen Radius*Beta Radius*TethLen Beta*TethLen Radius*Beta*TethLen Error Total 12/10/

49 Interaction plots for Tension

50 Main effects on tension

51 Graphical Sensitivity (contour plots) of each factor

52 Graphical Surface plots

53 Test Plan

54 Test Plan Varied wind speed: Dependent on environment Varied glider mass would be an additional test if time allows Component/System Tested Specification Tested Responsibility Completion Date Experimental Proof of Theoretical Model Tension Team 02/28/2014 Varied Tether Length Model Sensitivity Team 03/14/2014 Varied Wind Speed Model Sensitivity Team 03/28/2014 Varied Beta Angle Model Sensitivity Team 04/04/2014 Varied Flight Path Radius Model Sensitivity Team 04/11/2014 Varied Glider Mass Tension Team 04/18/2014

55 Risk Assessment - Full

56 Risk Assessment - High Priority/New

57 Project Plan

58 MSD II Plan

59 MSD II Plan (Continued)

60 Work Breakdown Matt Building glider, attaching bridal, flying tethered glider Paul - Building glider, attaching bridal, flying tethered glider Jon Machine parts, assemble base station Kyle - Machine parts, assemble base station Bill Create LabVIEW code, test DAQ equipment, Saj- Update project timeline, develop more detailed test plans from DOE, maintain transparency between team and customer/guides All Assist in base station build

61 Summary Engineering Requirements Glider Status Tether Design Base Station Design DAQ System Bill of Materials DOE ANOVA Analysis Test Plan MSD II Plan Work Breakdown Risk Assessment

62 Questions?