Single Line Tethered Glider Sub-System Level Design Review Team P14462 Kyle Ball Matthew Douglas William Charlock Jon Erbelding Paul Grossi Sajid Subhani
Team Introduction Team Member Major Sajid Subhani Paul Grossi Matt Douglas Jon Erbelding Kyle Ball Bill Charlock Industrial Engineer - Team Lead Mechanical Engineer Mechanical Engineer Mechanical Engineer Mechanical Engineer Mechanical Engineer
Agenda Project Description Review Engineering Requirements Review Top 3 Concepts from Last Review Concept Feasibility Glider Analysis and Feasibility Base Station Analysis and Feasibility Project Planning Work Breakdown Structure
Project Description Review Goal: Design, build, and test a tethered, small-scale, human-controlled glider. Glider Critical Project Objectives: Maintain maximum tension on the tether Sustaining horizontal and vertical flight paths Measure and record tether tension and position Understand the influential parameters for sustained, tethered, unpowered flight Tether Base Station Operator w/ controller
Engineering Requirements Metric No. Metric Marginal Value Ideal Value Units 1 Wingspan <=2 <1 m 3 System Cost <500 $ 4 Length of Looping Flight >2 >=3 min 5 Resolution of Tension Data <=0.1 <=0.01 N 6 Resolution of Angular Position Data <=0.5 <=0.1 deg 7 Typical Repair Time 5 3 min 8 Data Sampling Rate >=100 >=500 Hz 9 Minimal Operational Wind 5 Speed at Ground Level 2.5 m/s Maximum Operational 10 Wind Speed at Ground 5 10 m/s Level 11 Safe for User and Observer Yes Yes Binary 12 Number of Looping Trials >=25 Demonstrated >=30 Integer 13 Training Time (1st Time) <30 <20 min 14 Number of Left Right Horizontal Trials >=25 >=30 Integer 15 Tether length >=15 >=30 m 16 Glider Orientation Knowledge Bridle angle Bridle, yaw, attack, & roll angles deg Yellow: Major design Biege: DAQ Grey: Test flight White: System environment
Review of Top 3 System Concepts 3 Single Axis Load Cell IMU with Single Axis Load Cell 2 Potentiometers with Single Axis Load Cell
Glider Analysis
Choosing the Glider Bixler v1.1 EPO Foam Wing span: 1.4 [m] Chord length: 0.2 [m] Mass: 0.65 [kg] Middle mounted propeller Only EPO Foam $120 Phoenix 2000 EPO Foam Wing span: 2 [m] Chord length: 0.3 [m] Mass: 0.98 [kg] Front mounted propeller Reinforced $150
Price Sheet for Glider
Choosing the Glider The smaller Bixler glider creates less tension for a larger operating range Able to operate with an affordable load cell
Flight Orientation
Flight Orientation
Flight Analysis Wind Speed: ~ 11 mph
Flight Analysis Wind Speed: ~ 22 mph
Flight Analysis Wind Speed: ~ 44 mph
Qualitative DOE Tension must be less than 5000 [N] (1100 lbs) Slower wind speed: lower tension Larger flight path radius: lower tension Beta angle peaks: ~ 94-95 Tension peaks: ~ 20 [m] tether length
Quantitative DOE Choosing flight configuration Decision variables Beta angle Tether length Flight path radius Constraints Maximum allowable tension Observed wind speed
Bridle and Tether Setup Use a tension of 3000 lbs as an overestimate. Maximum allowable stress for Bixler glider: 30 MPa Bridle attached at two points on the fuselage causes structural failure at the wing root with 180 MPa
Proposed Tether and Bridle Design
Ideal Bridle Location Analysis Optimum tether location: 0.51 m from root. Optimum tether angle: 54 deg from airplane
Wing Stress Analysis
Wing Stress Analysis Maximum stress: 15 MPa
Fuselage Stress Analysis
Tether and Bridle Configuration
Base Station Analysis and Feasibility
Concept 1 2 Potentiometers and Single-Axis Load Cell
Vertical Rotation
Engineering Spec Considerations Metric No. Metric Marginal Value Ideal Value Units Resolution of Angular 6 <=0.5 <=0.1 degree Position Data δβ = δθ + δγ = 0.5 deg δγ = 0.5 δθ = cos 1 r + Lcos(δφ) L 2 + r 2 + 2rLcos(δφ) From application of Law of Cosines Solve for maximum allowable δφ such that the resolution requirement is met, and load cell begins to move
Static Analysis M o = Trsin δφ W LC dcos θ b M pot M bear = 0 T = M pot + M bear + W LC dcos(θ b ) rsin(δφ)
Dynamic Analysis M o = Trsin δφ W LC dcos θ M pot M bear = I LC α T = I LCα b + M pot + M bear + W LC dcos(θ b ) rsin(δφ) α b = dω b dt where ω b = ω prcos θ p L + r where θ p = ω p t
Horizontal Rotation
Static Analysis M o = Trcos(θ b )sin δλ M pot M bear = 0 T = M pot + M bear rcos(θ b )sin(δλ)
Dynamic Analysis M o = Trcos(θ b )sin δλ M pot M bear = I LC α b T = I LCα b + M pot + M bear rcos(θ b )sin(δλ) α b = dω b dt where ω b = ω prsin θ p L + r where θ p = ω p t
Concept 2 3 Single-Axis Load Cells
CAD Model Created 3-D model of the system in SolidWorks Works well when the ball joints are kept in tension as seen in Fig 1. Ball joints fail when they are put into compression as seen in Fig 2. 10/24/2013 Fig. 1 Subsystem Level Design Review Fig. 2 P14462
Base Station Cost Feasibility
Base Station Equipment Phidgets 3140_0 S Type Load Cell Bourns 3540S-1-103L Potentiometer
Initial Base Station Budget Comparison P14462 Purchase List for 3 Load Cell Base Station Part Description Unit Price Qty Individual Total Phidgets 3140_0 - S Type Load Cell 50 3 150.00 Ball End Joint Rod 3.78 6 22.68 Shipping 0.00 Total Order Price 172.68 P14462 Purchase List for Potentiometer Base Station Part Description Unit Price Qty Individual Total Phidgets 3140_0 - S Type Load Cell 50 1 50.00 Bourns 3540S-1-103L Potentiometer 20 2 40.00 Miniature Aluminum Base-Mounted Stainless Steel Ball Bearings ABEC-3 14.92 2 29.84 Flanged Open 1/2 Inch Ball and Roller Bearing 7.61 1 7.61 Shipping 0.00 Total Order Price 127.45
Project Planning Phase 1 Team Organization Problem Definition and comprehension Research complimentary projects Week 3 Presentation preparation Phase 2 Update critical needs on EDGE website Acquire Glider Flight Skills Functional Decomposition Benchmarking base stations Benchmarking marketable Gliders Determine PUGH Diagram Critical eng. theory ID and comprehension Week 6 Presentation preparation Phase 3 Price compare bought gliders/order glider Theoretical flight simulation development Use simulation to calculate feasible tension values Develop preliminary base station sketches and CAD models Preliminary base station calculations for feasibility Understand components of DAQ Identify critical components of DOE Week 9 Presentation preparation Phase 4 Budget approval Finalize base station calculations Fly glider and understand effects of tether Develop implementation of tether/bridal Investigate glider reinforcement options (Carbon fiber) Refine simulation to aid DOE Create algorithm to meet DOE needs Determine specific sensors and building materials Begin to develop/modify LabVIEW code for DAQ Week 12 Presentation preparation Phase 5 Order Materials Week 16 Presentation Gate Review - "Green Light" Week 1 Week 2 Week 3 Week 4 Week 5 Week 6 Week 7 Week 8 Week 9 Week 10 Week 11 Week 12 Week 13 Week 14 Week 15 Week 16 26-Aug 2-Sep 9-Sep 16-Sep 23-Sep 30-Sep 7-Oct 14-Oct 21-Oct 28-Oct 4-Nov 11-Nov 18-Nov 25-Nov 2-Dec 9-Dec Legend Complete WIP Incomplete
Project Planning Phase 3 Price compare bought gliders/order glider Theoretical flight simulation development Use simulation to calculate feasible tension values Develop preliminary base station sketches and CAD models Preliminary base station calculations for feasibility Understand components of DAQ Identify critical components of DOE Week 9 Presentation preparation Phase 4 Budget approval Finalize base station calculations Fly glider and understand effects of tether Develop implementation of tether/bridal Investigate glider reinforcement options (Carbon fiber) Refine simulation to aid DOE Create algorithm to meet DOE needs Determine specific sensors and building materials Begin to develop/modify LabVIEW code for DAQ Week 12 Presentation preparation Week 7 Week 8 Week 9 Week 10 Week 11 Week 12 7-Oct 14-Oct 21-Oct 28-Oct 4-Nov 11-Nov
Incomplete Tasks from Phase 3 Control and stability calculations DAQ system development (setup, code) Sensors analysis (calibration, implementation)
Work Breakdown Structure (10-12) Paul: Tether and glider reinforcement and DOE Jon: Finalize base station calculations, sensors and build materials Kyle: Finalize base station calculations, sensors and build materials Matt: Tether and glider reinforcement and DOE Saj: Continue to develop DOE, create DOE algorithm, team management Bill: Purchase glider, develop/modify LabVIEW for DAQ, sensors and build materials
Questions?