By Peter La Franchi in London

Turkey's Kalebaykar unmanned air vehicle joint venture flew a vertical take-off and landing (VTOL) UAV  demonstrator adapted from a model helicopter in June and is planning to fly a larger, more advanced VTOL testbed by November.

The June exercise saw the demonstrator perform 30 sorties, each of around 15min. These included a flight involving fully autonomous take-off, waypoint navigation to a landing zone 1km (0.5nm) away, precision landing on a 1m (3ft) square target point in 17kt (30km/h) wind conditions, and return to the launch point.

The larger demonstrator, again being based on a model helicopter, will have a 2.2m rotor disc and is currently being modified to support continued evolution of the autonomy suite and prepare it for transition to production standard.

Kalebaykar is jointly run by the Ankara-headquartered Baykar Machine and Kalekalip Aerospace companies.

The autonomous VTOL guidance and control system is based on algorithms originally developed by the joint venture for its Bayraktar mini-UAV, a hand-launched fixed-wing system now on order for the Turkish army.

That suite was based on linear control concepts, but the helicopter version has been significantly evolved to use non-linear techniques to deal with the VTOL demonstrator’s different flight dynamics, says Haluk Bayraktar, engineering manager with Baykar Machine. While the initial VTOL flights have been successful, further changes to the suite are expected to expand its capabilities, with the joint venture also running a benchtop testbed that uses simulation-based inputs to test system characteristics.

Kalebaykar plans to develop its own low-cost VTOL airframe in the 100-200kg (220-440lb) class, says Bayraktar, with this to be pitched at both the civil and military markets. However, the civilian market is seen as offering the more significant market opportunities in the near term.

The production VTOL system will carry a sensor suite derived from commercial products as part of keeping costs down, but will use smart imaging processing to provide higher-quality images. Vibration control for the sensor suite is being pursued as an element of the flight-control software system, primarily through active engine tuning.

The likely development time for the production version is around one year, Bayraktar says, with the autonomy suite being given priority over the airframe. “Effective UAV design needs to start with the autopilot”.

 

Source: Flight International