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The purpose of this paper is to provide an overview of the recent research on the interaction between flight mechanics and sensory/control systems in flies. It furthermore, explores the application to biomimetic micro‐air vehicles (MAVs).

A review of recent literature on flight in flies is given first, whereafter two biomimetic case studies are discussed; the optic flow sensor developed by a French team and the micro‐mechanical flying insect project at the University of Berkeley.

The paper discusses the many areas where biological knowledge on flight in flies can be used by designers of MAVs.

Fully autonomous MAVs, inspired by insect flight, could be useful in a wide range of areas including search‐and‐rescue, surveillance and for military purposes.

The paper gives an up to date overview of dipteran flight behaviour and points to ways in which this knowledge can be applied to MAVs. The paper should thus be useful for biologists wishing to collaborate with engineers as well as for engineers and sensor designers seeking inspiration from nature.

The purpose of this paper is to demonstrate the uncontrolled vertical takeoff of an insect-mimicking flapping-wing micro air vehicle (FW-MAV) of 12.5 cm wing span with a body weight of 7.36 g after installing batteries and power control.

The forces were measured using a load cell and estimated by the unsteady blade element theory (UBET), which is based on full three-dimensional wing kinematics. In addition, the mean aerodynamic force center (AC) was determined based on the UBET calculations using the measured wing kinematics.

The wing flapping frequency can reach to 43 Hz at the flapping angle of 150°. By flapping wings at a frequency of 34 Hz, the FW-MAV can produce enough thrust to over its own weight. For this condition, the difference between the estimated and average measured vertical forces was about 7.3 percent with respect to the estimated force. All parts for the FW-MAV were integrated such that the distance between the mean AC and the center of gravity is close to zero. In this manner, pitching moment generation was prevented to facilitate stable vertical takeoff. An uncontrolled takeoff test successfully demonstrated that the FW-MAV possesses initial pitching stability for takeoff.

This work has successfully demonstrated an insect-mimicking flapping-wing MAV that can stably takeoff with initial stability.

The purpose of this paper is to present the procedure and results from instrumented flight test performed on the flapping MAVs being developed by the authors. A test is performed using a test measurement system to obtain the real characteristics of the flapping vehicles during their flight.

The test is performed in an indoor flight test facility, equipped with a motion capture system and tracking cameras. Spatial position data are obtained from the vehicles with retro‐reflective tracking markers attached. A quantitative analysis is carried out through the investigation and interpretation of the test data for the flight performance assessment of the vehicles.

The finding of the analysis addresses that the test enabled the numerical measurement of vehicles' flying performance and shows the present vehicles have combined characteristics of both birds and insects.

The test metrics attempted in the present study are applicable to the test and evaluation of general flapping micro air vehicles. Thus, this testing method will be useful for the development of future micro air vehicle system.

Full‐scale instrumented flight test and measurement of performance parameters of flapping micro air vehicles other than visual observation are unprecedented and expected to present the guideline of systematic test and evaluation of flapping micro air vehicles.

The purpose of this paper is to provide a review of recent developments in miniaturised flying robots.

Following a brief consideration of micro‐ and nano‐aerial vehicles, the paper discusses recent US and European research into the development of miniaturised flying robots.

This paper shows that research into miniaturised flying robots is gaining pace and much is being funded by the US military. Two major strands of research are devices which mimic the flight dynamics of insects and living insect‐microtechnology hybrids (cyborgs). The technologies remain at an early stage of development but covert surveillance and intelligence gathering are key future applications.

The paper provides a technical review of the latest developments in miniaturised flying robots.

Vertical take-off is commonly adopted in most insect-mimicking flapping-wing micro air vehicles (FMAV) while insects also adopt horizontal take-off from the ground. The purpose of this paper is to study how insects adjust their attitude in such a short time during horizontal take-off by means of designing and testing an FMAV based on stroke plane modulation.

An FMAV prototype based on stroke plane rotating modulation is built to test the flight performance during horizontal take-off. Dynamic gain and decoupling mixer is added to compensate for the nonlinearity during the rotation angle of the stroke plane getting too large at the beginning of take-off. Force/torque test based on a six-axis sensor validates the change of aerodynamic force and torque at different rotation angles. High-speed camera and motion capture system test the flight performance of horizontal take-off.

Stroke plane modulation can provide a great initial pitch toque for FMAV to realize horizontal take-off. But the large range of rotation angles causes nonlinearity and coupling of roll and yaw. A dynamic gain and a mixer are added in the controller, and the FMAV successfully achieves horizontally taking off in less than 1 s.

The research in this paper shows stroke plane modulation is suitable for insect’s horizontal take-off

The aim of this paper is to investigate the effect of wing kinematics change on force generation produced by flapping wings.

Forces produced by flapping wings are measured using a load cell and compared for the investigation. The measured forces are validated by estimation using an unsteady blade element theory.

From the measurement and estimation, the authors found that flapping wings produced positive and negative lifts when the wings are attached with the +30° and −30°, respectively.

The authors quantified the characteristics of change in the force generation by flapping wings for three wing kinematics. The wing kinematics was modified by changing the initial wing attachment angle.

The result may be applicable to design of control mechanism for an insect‐mimicking flapping‐wing micro air vehicle, which has only wings without control surfaces at its tail.

The preliminary work may provide an insight for design strategy of flapping‐wing micro air vehicles with compact and handy configurations, because they may perform controlled flight even without control surfaces at their tails.

The work included here is the first attempt to quantify the force generation characteristics for different wing kinematics. The suggested way of wing kinematics change can provide a concept for control mechanism of a flapping‐wing micro air vehicle.

The purpose of this study is to experimentally analyse the effect of flexible and stiffened membrane wings in the lift generation of flapping micro air vehicle (MAV).

This is analysed by the rectangle wing made up of polyethylene terephthalate sheets of 100 microns. MAV is tested for the free stream velocity of 2 m/s, 4 m/s, 6 m/s and k^* of 0, 0.25, 1, 3, 8. This test is repeated for flapping MAV of the free flapping frequency of 2 Hz, 4 Hz, 6 Hz, 10 Hz and 12 Hz.

This study shows that the membrane wing with proper stiffeners can give better lift generation capacity than a flexible wing.

Only a normal force component is measured, which is perpendicular to the longitudinal axis of the model.

In MAVs, the wing structures are thin and light, so the effect of fluid-structure interactions is important at low Reynold’s numbers. This data are useful for the MAV developments.

The effect of chord-wise flexibility in lift generation is the study of the effect of a flexible wing and rigid wing in MAV. It is analysed by the rectangle wing. The coefficient of normal force at different free stream conditions was analysed.

OPTIMIZATION of wing design aims at finding the best compromise between conflicting aerodynamic requirements and considerations of structure weight and stiffness. Since the profile drag of a laminarizcd aircraft is very small, the induced drag has to be correspondingly reduced for proper matching. Reduction of induced drag can only be obtained, for a given dynamic pressure at the cruise, by increasing the span, and that reflects on structure weight.

The purpose of this paper is to present an approach to employ evolvable hardware concepts, to effectively construct flapping‐wing mechanism controllers for micro robots, with the evolved dynamically complex controllers embedded in a, physically realizable, micro‐scale reconfigurable substrate.

In this paper, a continuous time recurrent neural network (CTRNN)‐evolvable hardware (a neuromorphic variant of evolvable hardware) framework and methodologies are employed in the process of designing the evolution experiments. CTRNN is selected as the neuromorphic reconfigurable substrate with most efficient Minipop Evolutionary Algorithm, configured to drive the evolution process. The uniqueness of the reconfigurable CTRNN substrate preferred for this study is perceived from its universal dynamics approximation capabilities and prospective to realize the same in small area and low power chips, the properties which are very much a basic requirement for flapping‐wing based micro robot control. A simulated micro mechanical flapping insect model is employed to conduct the feasibility study of evolving neuromorphic controllers using the above‐mentioned methodology.

It has been demonstrated that the presented neuromorphic evolvable hardware approach can be effectively used to evolve controllers, to produce various flight dynamics like cruising, steering, and altitude gain in a simulated micro mechanical insect. Moreover, an appropriate feasibility is presented, to realize the evolved controllers in small area and lower power chips, with available fabrication techniques and as well as utilizing the complex dynamics nature of CTRNNs to encompass various controls ability in a architecturally static hardware circuit, which are more pertinent to meet the constraints of micro robot construction and control.

The proposed neuromorphic evolvable hardware approach along with its modules intact (CTRNNs and Minipop) can provide a general mechanism to construct/evolve dynamically complex and optimal controllers for flapping‐wing mechanism based micro robots for various environments with least human intervention. Further, the evolved neuromorphic controllers in simulation study can be successfully transferred to its hardware counterpart without sacrificing its anticipated functionality and realized within a predictable area and power ranges.

Insects depend on the spatial, temporal and spectral distribution of light in the environment for navigation, collision avoidance and flight control. The principles of insect vision have been gradually revealed over the course of decades by biological scientists. The purpose of this paper is to report on bioinspired implementations and flight tests of these sensors and reflexes on unmanned aerial vehicles (UAVs). The devices are used for the stabilization of UAVs in attitude, heading and position. The implementations were developed to test the hypothesis that current understanding of insect optical flight control systems is feasible in real systems.

Design was based on behavioral and anatomical studies of insects. The approach taken was to test the designs in flight on a UAV.

The research showed that stabilization in attitude, heading and position is possible using the developed sensors.

Partial alternatives to magnetic, inertial and GPS sensing have been demonstrated. Optical flow and polarization compassing are particularly relevant to flight in urban environments and in planetary exploration.

For the first time the use of multispectral horizon sensing, polarization compassing and optical flow-based heading control have been demonstrated in flight.