drones-an introduction to design
Published in: Design
Transcript
- 1. Background • Drones are UAVs(unmanned aerial vehicles) • Flown remotely • Highly trained men operated many in a control room • Used to target highly dangerous enemies from afar • Usually very precise • Sometimes excessive casualties(civilian) • Limits our military casualties
- 2. Why have drones been in the news so much in recent years? Technological advances allowing unmanned flying objects to be accurately guided over large distances. Better intelligence gathering on the ground, which makes it possible to pinpoint and strike high-value military targets while keeping civilian casualties and other collateral damage as low as possible.
- 3. Drones are- • Extremely effective at disabling enemies • Limits our military losses • Gives us a reconnaissance of areas • Used to patrol borders • Piloted by some of the most capable soldiers in our military.
- 4. Some design parameters Aerodynamics Payload Endurance Speed and range Communications Navigation system Launch and recovery
- 5. payload o The carrying capacity of an aircraft or launch vehicle, usually measured in terms of weight. E.g. Satellite, space probe for a rocket Warhead for ballistic missiles
- 6. Aerodynamics The most important part in any aircraft design. The pressure difference produces lift. Also creates drag. Minimize the drag .
- 7. Endurance 1 hr for a close-range surveillance system. 24 hr+ for a long-range surveillance . Mass of the fuel carried is a function of the required endurance. The mass of the fuel to be carried may be as low as 10% of the aircraft weight for close-range UAV. Rises to 50% of its weight for the long-endurance aircraft.
- 8. Categories of systems based upon vehicle types HALE-High Altitude Long Endurance. Over 15000 altitude and 24+ hr endurance. wingspan-39.9m max. endurance-35hr max. altitude-19,800m Payload mass-1,360kg GLOBAL HAWK
- 9. Categories of systems based upon vehicle types MALE – Medium altitude long endurance Medium altitude long endurance. 5000-15000m altitude and 24hr endurance wingspan-20m Payload -mass 230kg predator-B
- 10. Categories of systems based upon vehicle types TUAV – Medium Range or Tactical UAV Range of order between 100 and 300 km wingspan 6.57m endurance of 4 h 30 min 380kg empty weight DRDO-Nishant
- 11. Navigation system Necessity of knowing the position of UAV Current popular method of position fixing is and navigation between points is by use of GPS The GPS give continuous positional update.
- 12. Continued • For non-autonomous operation other means of navigation are possible 2. Radar tracking. 3. Direct reckoning. Also known as inertial navigational system
- 13. Communications The principal requirement is to provide the data links between the CS and the aircraft. The transmission medium is most usually radio frequency. The tasks of the data links are usually as follows Uplink (i.e. from the CS to the aircraft) Downlink (i.e. from the aircraft to the CS)
- 14. Launch , Recovery and Retrieval Equipment. Launch equipment- required for those air vehicles which do not have a vertical flight capability, nor have access to a runway. • Takes the form of a ramp . Recovery equipment- required for aircraft without landing capability. • Takes the form of a parachute. Carousel apparatus into which the aircraft is flown and caught. Retrieval equipment. Required of transporting the aircraft back to its launcher.
- 15. Launching of UAV Recovering a UAV
- 16. Selection of Engines The power system for a UAV includes an energy source Different types of engines found in UAVs are Turbofans, Piston Engines, Rotary, Turboprop, Electric etc. As the weight of the plane increases so does the size of the engine. The lighter, smaller UAVs tended to use electric motors. The heavier, battle ready UAV tend to use Turbofan or Turbo shaft engines.
- 17. Turbo shaft engine
- 18. Design For Stealth There are three main reasons why it is desirable that a UAV system remains undetected in operation. • Air vehicle should remain undetected whilst on a reconnaissance/surveillance mission . • To protect the air vehicle from loss due to enemy countermeasures. • Minimising environmental disturbance.
- 19. Ways to improve stealth of UAVs • Reduce Acoustic Signature. • Design quieter engines. • Use of silencers for reducing exhaust noise. • Flying at high altitudes. • Using sound absorptive materials. • Mounting engines above wings. • Both air intake and exhaust should be directed skyward.
- 20. Ways to improve stealth of UAVs • Minimise Radio/Radar Signature • To manufacture appropriate areas of the UAV from radar- translucent material such as Kevlar or glass. • To cover the external surfaces of the aircraft with RAM (radar absorptive material). • To shape the aircraft externally to reflect radar pulses in a direction away from the transmitter.
- 21. B-2 Spirit stealth bomber of the U.S Air Force
- 22. Against the use of drones Immoral Civilian casualties Angers many people in foreign countries(infringe upon sovereignty) Can be hacked or given viruses
- 23. Current generation of drones • The current generation of drones such as the MQ- 1PREDATOR and MQ-9REAPER drones are capable of flying reconnaissance as well as offensive missions from anywhere around the world. • 3000lbs payload which it can deliver on the click of a button
- 24. Future of UAVs wide application in military and civilian roles Fire-fighters to use them in search and rescue operations Police for monitoring crowds and traffic May one day replace pilots altogether
- 25. REFERENCES Unmanned Aircraft Systems: UAVS Design, Development and Deployment (Aerospace Series). Reg Austin. MECH ENG 3016 AERONAUTICAL ENGINEERING Dr. Maziar Arjomandi CLASSIFICATION OF UNMANNED AERIAL VEHICLES , The University of Adelaide . en.wikipedia.org Google Image Search