Pteryx UAV

Pteryx UAV^[1] was a Polish Miniature Unmanned Aerial Vehicle (UAV) designed for civilian use. It was manufactured and sold by Trigger Composites.^[2] The machine was both a flying remote control (RC) model and pre-programmed vehicle. It was awarded the Innowator Podkarpacia medal for innovative design in the category of micro-enterprises of the Podkarpacie region in 2010.^[3]

Pteryx UAV
Pteryx UAV, with the camera mounted sideways.
General information
Type	UAV
Role	Photography
National origin	Poland
Manufacturer	Trigger Composites

Origin

The Pteryx UAV uses a custom derivation of the FLEXIPILOT software, designed by Aerial Robotics engineering group^[4] for photomapping purposes and civilian use.

The avionics and flying platform are capable of full operational capability without using an active transmitter or ground station.

Capabilities

Digital Surface Model of a motorway interchange construction site.

Bezmiechowa airfield 3D Digital Surface Model

4.5km² orthophotomap extracted from data collected during 1h flight

• Delivering data for generating digital elevation models using external photogrammetric software and orthorectification procedure^[5]

• Delivering data for precision agriculture by creating surface maps using mosaicking software
• Construction site and long-range linear mapping (up to around 40 km both ways with 2-hour flight time, reserve included)^[6]

• Carrying custom research equipment

The camera mount contains either pre-installed compact digital camera or can be exchanged for other equipment.

The camera can be mounted down-looking (nadir photography) or side-looking (oblique photography).

The whole head can be tilted in flight using the RC transmitter, while reducing stabilization travel to one of the sides.

Capabilities

• Flying multiple missions per day without being required to reprogram the autopilot, using waypoints.
• Exchangeable mission package
• Single button operation
• Fully enclosed camera head
• Ability to accommodate a weight range 200g-1000g
• Takeoff by catapult
• Landing through use of a parachute

Camera

The aircraft provides positions of the photos taken, and has storage for 8000 events. Ground-projected positions include the following error margins:

• GPS position error up to 5m.
• Altitude drift (up to 5m per 1 hour of flight)
• Camera head stabilization precision (transients up to 5°)
• Fuselage pitch due to turbulence (up to 8° during hot weather, typically 2° in winter)
• Camera mounting error (typically 1–4° if not calibrated)
• Heading/yaw error (the aircraft performs crabbing in presence of wind)

Typical orthophoto map precision (mean reprojection errors):

• 10 centimetres (3.9 in) horizontal
• 30 centimetres (12 in) vertical
• around 2.5m global shift to be removed with a few locally measured points

Data processing strategies

Several data processing approaches are possible depending on application:

• Direct photo examination
• Non-georeferenced image stitching using free software
• Using free 3D modelling services, as mentioned in examples section
• Importing each photo as ground overlay in Google Earth (semi-automatic with supplied software)
• Using pre-paid service based on cloud computing, yielding a result in hours (delivers orthophotomap and optionally DSM)
• Local processing using specialized GIS software created specifically for large scale image mosaicking (delivers orthophotomap and optionally DSM)

Aircraft components

• Fuselage
• 3-section wings with mounting screws
• Horizontal stabilizer section
• Parachute

Other required equipment

• LiPo batteries
• Laptop or netbook
• Compact digital camera
• RC controller compliant with local laws (see Radio-controlled aircraft Transmitting and Receiving Frequencies)

General characteristics

Masses:

• Maximum takeoff weight 5.0 kg

Dimensions:^[7][8]

• Wingspan: 2.8 m
• Length: 1.4 m
• Height: 0.33 m
• Propulsion: brushless DC electric motor and rechargeable lithium polymer battery
• Endurance: 55min with 1 kg payload, 120min with 450g payload

V speeds:

• V_C: around 50 km/h
• V_S: 34–38 km/h depending on TOW
• V_A: 120 km/h
• V_NE: 160 km/h

Flight altitude:

• Service Ceiling 3000m Pteryx Lite
• Service Ceiling 1200m Pteryx Pro
• Cruise altitude 100–520m AGL, 250m typical – dictated by photo resolution

Handling:

• Assembly time: Around 5 minutes.
• Materials: Custom fiberglass composite material covered with durable red gelcoat, carbon fiber and Kevlar reinforcements, wood and other plastics. Wooden or all-composite wings are offered.