The control power of micro UAVs, the technical challenges of micro UAVs

The Royal Academy of Military Sciences, located on Cranfield University's West Winham campus in the United Kingdom, plays a pivotal role in aerospace research and is a frontrunner in the study of micro-UAV flight systems. Dr. Rafal, the institute's chief researcher, believes that the use of insect-like flapping wings as a flight control system can provide a certain degree of maneuverability at low speeds, which is not possible with existing platforms. Since 1998, the institute has been developing an insect-like flapping wing flight control system, and has established two mechanical devices on a static platform.

The purpose of establishing such a platform for aerodynamic research is twofold: first, to study the feasibility of insect-like flapping wing mechanical devices; The second is to explore the aerodynamics of micro-UAVs. Although some fairly successful mathematical models have been developed, more data needs to be collected, especially for flapping wing micro-UAVs. Because the principles of insect flight are still poorly understood, many of these problems are difficult to explain with ordinary aerodynamic theories.

In order to change the parameters, the current model needs to be decomposed. The researchers expect to improve their maneuverability by improving the insect-like flapping wing mechanism currently under development, such as using asymmetrical wings. This involves both the study of aerodynamics and the study of flight dynamics.

Since the principle of insect flight control is not yet known, what needs to be done at the moment is to take a push-pull approach, advancing in engineering and pulling in biological science. However, it is now possible to replicate most of the maneuvering characteristics of insects, with the only obstacle being size. The average size of houseflies is only 10 times the size of the current mechanism, so it is important to find out to what extent the aerodynamic and flight dynamics characteristics of the two are identical.

This is not just a simple problem of geometric scaling, but the interrelationship between aerodynamic properties and inertial forces needs to be solved. Aerodynamic force can be generated by flapping wings, but how can it be applied to the fuselage?

For a micro drone with a wingspan of 15 cm and a housefly, will the effect of flapping the wings be the same? At present, there is some superficial understanding. From a purely aerodynamic point of view, what happens in flight with smaller insects can also happen with larger micro-UAVs.

Small insects may encounter turbulence or sudden gusts of wind in flight, and 15cm drones may also encounter them, how to increase their natural stability to maintain their course and carry out the operator's maneuvering commands? If the microcomputer needs to image a target, how can the reticle be stabilized? There has been some progress in the study of these issues, but this is only the beginning.

Full autonomy is essential for future micro-UAVs, otherwise only a large number of soldiers can be trained to control thousands of micro-UAVs.

The micro-drone combat environment is mainly between canyons and urban buildings, which means that the use of micro-drones is often non-direct-looking. Micro UAVs need to maintain communication with operators when flying in the air, but due to the limitations of volume and mass, microwave communication can only be used at present. Although microwaves can transmit large amounts of data for live television broadcasts, they cannot penetrate walls, which is a problem that needs to be solved urgently.

For non-line-of-sight data transmission, there are a number of technologies and solutions, one of which is to deploy a large number of larger UAVs over the required area to provide the network connectivity required for the entire network and transmit information in real time. Satellite communication is another way to deal with non-line-of-sight data transmission, but there are problems with excessive power consumption or potato consumption, and it also requires a communication relay station in the air to connect with the network, which can be another aircraft or satellite.

If the micro-drone is not flying under the control of the operator, then its autonomy is crucial. GPS navigation systems have been miniaturized to a size suitable for micro-UAV use, and tests have been conducted, but there is still a certain gap between the level required for autonomous flight. Micro-UAVs need to have a certain degree of autonomy beyond the limits of programmed flights, so that the UAS can fly completely independently to the desired area and collect data, and then transmit the data to combat units or networks.

This is not possible at the moment. The development of the autonomy of micro-UAVs places demands on communication bandwidth and energy. The more data is transmitted, the more energy is consumed, and the more radio spectrum is required.

In order to be used on the battlefield, micro drones also need to carry a variety of reconnaissance sensors, such as television cameras, infrared, audio and biochemical detectors. These must be miniature sensors that are ultra-lightweight, so component miniaturization is key to the development of sensor technology.

The development of the micro-UAV 1 began in the mid-1990s, the first flying prototype appeared in the late 1990s, and in 1996 the US Defense Advanced Research Projects Agency awarded the Voyage Company a development contract to conduct a feasibility study for the manufacture of micro-UAVs, the micro-UAV combat environment is mainly between canyons and urban buildings, which means that the use of micro-UAVs is often non-direct-looking. Micro-UAVs Unmanned aerial vehicles (UAVs) have become a widely recognized member of the battlefield, and in just a decade, they have gone from an occasional role in the arsenal of commanders to an indispensable role in conflict operations.