The document discusses blimps and their anatomy. A blimp, or non-rigid airship, is an airship without an internal supporting framework. It has key components like stabilizers, an envelope, motors, a gondola, and propellers. The document also discusses how to calculate lift using helium versus other gases based on density and volume. Rigid envelopes are more efficient than latex balloons due to pressure differences. Various envelope designs and propulsion options are presented, along with a potential controller architecture and sensor options like gyros, accelerometers, GPS, digital compasses, ultrasonics, pressure sensors, IR, and vision.

1. MEAM 610BLIMPSMohit Bhoite and Saurabh Palan

2. IntroductionBlimpsAnatomyDesignControlSensing

3. Anatomy of a Blimp“A blimp, or non-rigid airship, is an airship without an internal supporting framework or keel.” - wikiStabilizers EnvelopMotorsGondolaPropellers

4. HELIUM - Calculating LiftAt standard temperature and pressure, mass density of Air : ρair= 1.293 kg/m3 Helium : ρHe=0.178 kg/m3 Neon: ρHe= 0.9 kg/m3 Wload = [(ρair– ρHe) x volume – Wenv] KgGrade A Helium gas = 99.995% He and 0.005% NeWload= [(ρair-0.99995ρHe - 0.00005ρNe) x volume – Wenv] Kg

5. HELIUM - Calculating LiftWload= [1.1149 x volume – Wenv] KgThumb rule : 1m3 of helium can lift 1.1 kg of load

6. Latex Balloons vs. Rigid EnvelopsWhich one is better?Balloons have internal pressure much higher than atmospheric => unnecessary helium mass => no extra liftRigid envelops will have pressure equivalent to atmospheric pressure => better efficiency

7. Envelop Designs

8. Envelop DesignsOff-the-shelf OptionsCost$25, 7cu feet$12$13, 5cu feet$4, 3’ dia

9. PropulsionDC Brushed motors + PropellersFlapping wings/fins !

10. Propeller Placements

11. Propeller Placements

12. Propeller Placements

13. Controller ArchitectureSensorsMain Controller(uP, uC)Motor DriverMotors, ServosCameraWireless Link

14. SensorsGyrosAccelerosGPSDigital CompassUltrasonicPressure sensorIRVision

15. SensorsGyrosAccelerosGPSDigital CompassUltrasonicPressure sensorIRVision

16. Digital CompassDevantech, acroname.com, $57

17. Digital CompassI2C interface

18. 2.7 to 5.2V supply range

19. 1 to 20Hz selectable update rate

20. True drop-in solution

21. 0.5 degree heading resolution

22. 1 degree repeatability

23. Supply current : 1mA @ 3VSparkfun.com, $60

24. Pressure SensorsBarometric pressure sensing for altitude measurementCan achieve resolution of about 10cm at sea levelPressure decreases at the rate of 100 millibars per 800 meters$55

25. Thank you!