Team Logo Here (If You Want) CanSat 2013 PDR: Team 1276 (Garuda) 1 It has three important parts Descent control system Material Selection Egg protection

Team Logo Here (If You Want) CanSat 2013 PDR: Team 1276 (Garuda) 2 DESCENT CONTROL SYSTEM

Team Logo Here (If You Want) DESCENT CONTROL Most important part of CanSat Need: To bring the descent rate to a value such that components are not affected by final impact with ground Devices : Drag or Lift Generating CanSat 2012 PFR: Team 7634 (Garuda) 3

Team Logo Here (If You Want) Descent Rate Calculations Formula used for calculating the terminal velocity Where V t = Terminal Velocity W= Payload C d = Coefficient of Drag (1.5 for round and hemisphere) ρ =Density of Air (It varies from 600m to ground level) A= Equivalent area of Parachute or cluster of them ((π*d 2 )/4) CanSat 2013 PDR: Team 1276 (Garuda) 4

Team Logo Here (If You Want) DESCENT RATE CONTROL : Our Design Objective: To reach the descent rate of 20 +/- 1m/s Procedure:  Determination of basic dimensions and attributes of parachute through preliminary calculations  Determination of material’s coefficient of drag.It can be determined through Ansys Fluent analysis.  Experimentation to determine actual descent rate Problems encountered:  It is not possible to find heights to test the parachute  More the height, more is the drift; hard to relocate parachute  Difficult to find out terminal velocity CanSat 2012 PFR: Team 7634 (Garuda) 5

Team Logo Here (If You Want) Descent Control Strategy Trade & Selection : Our Method DRAG MECHANISM SELECTION Drag MechanismBenefitsProblemsDecision Parachute(without spill hole) Large coefficient of dragDrifting, OscillationsNot to be used Parachute(with spill hole) Reduced drifting and oscillations, Lesser material and weight Descent rate has increased Selected Streamers Faster recovery, Reduced Drifting, Lesser drag Heavier, Occupies larger volume Not to be used Paraglide Descent control methods include drag and lift Drift need to be there to enable it to control descent via lift Not to be used CanSat 2013 PDR: Team 1276 (Garuda) 6

Team Logo Here (If You Want) Descent Control Strategy Trade & Selection : Our Method CanSat 2013 PDR: Team 1276 (Garuda) 7 MaterialBenefitsProblemsDecision Ripstop nylon Lower porosity, Dyed in many colours, Easily available Slightly expensiveTo be used Mylar Thin, Light, C d =0.14(approx.) Not easily availableCan’t be used FlexAlternative to MylarHeavy and more porousNot to be used Retired Hot air balloon Alternative to ripstop nylon as it will be less expensive Fewer colour options, Need to be washed several times to get the smell of the gas out, need to be replaced after certain time of usage Can’t be used MATERIAL SELECTION

Team Logo Here (If You Want) Descent Control Strategy Trade & Selection : Our Method PARACHUTE SHAPE SELECTION ShapePayloadDimensionDescent rateDecision Round710g10cm42.83m/sSelected Square710g10cm53.53m/s Not to be selected Hexagon710g10cm47.06m/s Can be considered CanSat 2013 PDR: Team 1276 (Garuda) FINAL DECISION: Round shape is selected be because it provides minimum descent rate 8

Team Logo Here (If You Want) Container Descent Control Strategy Trade & Selection Color Selection Parachutes are ordered from FruityChutes.com which provide varied color parachutes Colored parachute is preferred because of its ease in detection Shock Force Survival & DCS Connection Parachute is connected to envelope via strings that can take up shock of sufficient magnitude Pre Flight review testability Plumb line with very low weight as compared to payload Length of string to be very long Calculate the descent rate by simple formula- CanSat 2013 PDR: Team 1276 (Garuda) 9

Team Logo Here (If You Want) OTHER DRAG DEVICES UMBRELLA DESIGN –Compressed Air Transport (Lift Providing Mechanism)  Air is highly compressed(about 20atm) and flows through nozzles to provide upper thrust  Air need to be compressed at very high pressure  Container material not easily available and will lead to increase in weight  Experiments showed that air compressed at 6 atm in 4L container with 3 nozzles provided thrust for just 5-6 seconds CanSat 2012 PFR: Team 7634 (Garuda) 10

Team Logo Here (If You Want) CanSat 2013 PDR: Team 1276 (Garuda) 11 Material Selection

Team Logo Here (If You Want) Material selection for the payload Material Selection Requirement: It should be light in weight Easily available in nearby market Easy to manufacture Material Properties CanSat 2012 PFR: Team 7634 (Garuda) 12 How to select the material Using data base software like CES Test its properties on FEM software

Team Logo Here (If You Want) Problem Statement CanSat 2013 PDR: Team 1276 (Garuda) 13 Propose a descent control system for a payload of 800gms with these requirements: It should have an initial size of 250X130mm containing all the components for descent control. During flight, it can expand to any dimension. At the ground, it should have a velocity of around 8-10m/s to ensure the safe landing of the payload.