DE102005022706A1 - Helicopter especially for observation has multi rotor drive with rotor location outside the field of forward view of an onboard camera - Google Patents

Abstract

A helicopter for observation, e.g. an unmanned aircraft with a variable position onboard camera (5) has three of more rotors and no tail rotor. The rotors are driven by separate of combined drives. One or two of the rotors are in front of the camera when viewing forward. These rotors are displaced by up to 20 percent of their diameter from the general horizontal plane so as not to be in the forward field of view of the camera.

Description

background the invention

helicopter are rotorcraft aircraft with at least a motor-driven rotor. There are numerous embodiments with different numbers of rotors in different arrangements.

little one and light helicopters are gaining more and more as flying camera carriers in importance. It dominates the classic embodiment with a main rotor, primarily for lift generation, and a tail rotor for torque compensation.

disadvantage this concept: about 20% of the drive power will be for the tail rotor needed and do not stand for the buoyancy available (reduced energy efficiency). Furthermore, the mechanics of the control is relative costly and complicated (collective & cyclic pitch, stabilization systems Etc.). Furthermore feature Helicopters of this type over a rather low flight stability.

at The drive technology of helicopter camera carriers can be found in internal combustion engines most frequently. However, the electric drive is on the rise. Some advantages: quiet, reliable, whatever the weather Operating behavior, fine controllability, low vibration. Of the Trend towards the electric drive is accelerated by the continuous development electrical energy storage, towards ever higher energy and power density.

nevertheless is far from reaching the level of fossil fuels here, therefore the energetic efficiency in the development of electric helicopters always a big one Role plays to sufficiently long flight times and sufficient payloads to achieve. Above all, consistent lightweight construction is important.

A newer type of electrically powered helicopters, namely the with three or more lifting units (so-called multi-rotor helicopters) is as a flying camera carrier especially interesting. Under lifting unit, the combination is at least a rotor understood with at least one rotor driving motor. The lifting units can also contain other components, eg. B. gear or speed controller. The combination of exactly one rotor with exactly one motor is the most frequent execution a lifting unit. The axes of the rotors are typically (approximately) vertical. The rotors serve primarily the lift generation - therefore the name lifting unit.

helicopter with four lifting units allow a control of all axes alone over the Speed of the four lifting units, ie without mechanics except rotating Shafts, in particular without collective and cyclic rotor blade adjustment. 4-rotor helicopters can Accordingly, be built mechanically very minimalist. Another Advantage: The power-consuming tail rotor can be omitted.

In the plan view are the lifting units of 4-rotor helicopters almost always arranged at the corners of a square, often at the corners a square. The center distances are usually so big that the circular surfaces defined by the rotors are straight do not overlap. With that you can the rotors are arranged on one level without touching (standard construction).

These Helicopter type has been equipped with various cameras. adversely at previous solutions is that with horizontal camera alignment parts of the helicopter can be seen in the camera image. This bothers z. B. in aesthetic Photography of landscapes and buildings.

Of the Invention is the object zugunde, an efficient, compact To provide multi-rotor helicopter with a camera in which at approximate horizontal camera direction in hover, no parts of the helicopter can be seen in the camera image, in particular no rotor blades.

Short outline the invention

According to the invention the object is achieved with a helicopter with three or more lifting units, each with at least one rotor and at least one rotor driving the electric motor, and with we at least one camera, wherein at least one rotor is arranged in front of the camera, the rotor circuit surface in hover position of the helicopter in approximately horizontal shooting direction of the camera completely above, below or to the side of the opening portion of the camera and the rotor circuit surfaces of all rotors of the helicopter are outside the opening range of the camera , This ensures that no parts of the helicopter can be seen in the camera image, including no rotor blades.

The Hover position is the attitude that the helicopter hovers in a calm air. The recording direction is determined by the optical Defined axis of the lens of the camera. By "approximately horizontal" is meant that the angle deviation from the horizontal maximum about 5 degrees is. The opening area the camera is a space segment in front of the camera; he is going through the opening angle bounded from edge to edge. There are two opening angles: one vertical from upper edge to lower edge of image and a horizontal one from the right to the left edge of the picture. The bisector of an opening angle is typically on the optical axis.

To a first embodiment According to the invention, a rotor may be arranged in front of the camera, which in Hover position by at least about 20% of the mean rotor diameter the rotors is above another rotor. It can too two rotors are arranged in front of the camera, in hover position at least about 20% of the average rotor diameter of the rotors above one other rotor.

Two Rotors can be arranged in front of the camera, whose rotor circuit areas on the right and left of the opening area the camera are, so one right and one left.

The Mass of the camera can be more than about 20% of the takeoff mass of the Helicopter amount. The camera can have an opening angle between about 20 degrees and about Realize 45 degrees, horizontally and / or vertically. She also can be provided with facilities for storing images.

Of the Center of gravity of the camera can be less than about 50% of the average rotor diameter of Rotors are located away from the center of gravity of the complete helicopter. He can also less than about 50% of the mean rotor diameter of the rotors from the buoyancy center be removed from the helicopter.

Of the Helicopters can have a take-off mass of less than about 5 kg preferably less than about 1 kg. The overall dimensions of the helicopter can below about 2 m, preferably less than about 1.2 m.

Short description the drawings

Further Aspects and advantages of the invention will become apparent from the following Description of preferred embodiments, which will be explained with reference to the following figures.

1 shows a plan view of a helicopter according to the invention with a camera according to a first embodiment of the invention (Example 1);

2 shows a longitudinal view of the helicopter after 1 ;

3 shows a plan view of a helicopter according to the invention with a camera according to a second embodiment of the invention (Example 2);

4 shows a longitudinal view of the helicopter after 3 ;

5 shows a plan view of a helicopter according to the invention with a camera according to a third embodiment of the invention (Example 3);

6 shows a longitudinal view of the helicopter after 5 ;

7 shows a plan view of a helicopter according to the invention with a camera according to a fourth embodiment of the invention (Example 4); and

8th shows a longitudinal view of the helicopter after 7 ,

description preferred embodiments the invention

First, for the embodiment of the 1 and 2 (Example 1). The pictures show a remote controlled 4-rotor helicopter 1 which is suitable for aerial photography. The helicopter 1 comprises a total of four lifting units 2 , The lifting units 2 each have a rotor 3 each with two rotor blades 7 and an electric motor driving the rotor 4 , The lifting units 2 are on a support frame 8th attached and connected by this. The four lifting units 2 are identical except for the direction of rotation. Two turn to the left and two to the right.

The shoring 8th also carries a camera 5 with storage possibility of the camera images as well as a central control unit 10 , In the control unit 10 integrated are a transmitter for wireless transmission of camera images to the ground, a receiver for receiving the remote control signals from the ground, electronics for stabilizing the attitude and for controlling the lifting units and the central power supply (battery).

The helicopter 1 is remotely controlled manually to camera image. But he can also be equipped with an automatic flight guidance. The camera 5 is triggered remotely.

The technical data of the helicopter 1 are as follows: Rotor diameter: 380 mm Rotor speed: 900 1 / min Power requirement (hover): 25 W Flight time: 20 min Take-off weight: 350 g Overall dimensions (length, width): 800 mm

The shooting direction of the camera 5 in the hover of the helicopter is oriented in the horizontal direction, namely to the front. The optical axis of the camera lens extends in the direction of the longitudinal axis of the helicopter 1 , Optionally, the camera can also be pivoted on the support frame 8th to be appropriate.

Width and height of rectangular camera image from camera 5 stand in the ratio 4: 3. The horizontal opening angle of camera 5 in the exemplary embodiment is 40 degrees, the vertical 30 degrees. The angles are in the 1 and 2 located. The opening angle can vary within wide limits or be made adjustable (zoom function).

The focus of the helicopter 1 and the focus of the camera 5 lie close to each other, with a horizontal distance of about 20 mm (about 5% of the rotor diameter d). The same applies to the distance of the camera center of gravity to the center of lift (point of application of the resulting buoyancy force). The lift center lies in the plan view in the geometric center of the four lifting units and in the side view at the average height of the rotors. The mass of the camera 5 is in the exemplary embodiment about 30% of the take-off mass of the helicopter.

Two lifting units 2 are in front of the camera 5 arranged, the other two behind. The circular surfaces of the rotors 3 the lifting units in front of the camera 2 lie above the opening area of the camera 5 , as in 2 to recognize. The two front rotors 3 are higher by one measure h than the two rear rotors 3 , The dimension h is about 40% of the rotor diameter d. With this rotor assembly, a free horizontal camera view can be achieved under the two front rotors.

helicopter 1 is built very compact to him even in confined spaces, such. B. inside buildings, to be able to use. The axial distances of the lifting units are just so great that the rotor blade tips do not touch each other in plan view. Thus, with small outer dimensions much rotor surface is accommodated. The low circular area load (mass per rotor area) contributes significantly to the high energy efficiency of the helicopter.

At the camera 5 it is a commercial digital camera. Although it is relatively light at around 100 g in absolute terms, it still carries a large part of the take-off weight. Alternatively, the images transmitted by wireless can be stored on the ground, but storing them in the camera has the advantage that the image quality is not improved depends on the radio link.)

• • Die Hubeinheiten werden gleichmäßig belastet Durch die mittige Platzierung der Kamera liegt auch der Gesamtschwerpunkt des Hubschraubers dort. Jede Hubeinheit trägt daher zu gleichen Teilen am Gesamtaufrieb bei. Die Leistungsreserve der Hubeinheiten ist gleich hoch.
• • Keine störenden Roll- und Nickmomente beim horizontalen Beschleunigen des Hubschraubers Auftriebsmittelpunkt (Angriffspunkt der resultierenden Auftriebskraft) und Schwerpunkt (Angriffspunkt der resultierenden Massenkraft) liegen näherungsweise in einer Höhenebene. Daraus resultiert ein neutrales Flugverhalten. Bei einem größeren, vertikalen Abstand dieser Punkte zueinander (z. B. wegen einer sehr tief montierten, relativ schweren Kamera) würden beim horizontalen Beschleunigen oder Verzögern des Hubschraubers Roll- bzw. Nickmomente auftreten, die beträchtliche Unruhe in das Fluggerät bringen können und es im Extremfall unbeherrschbar machen.
• • Geringe Massenträgheit durch Massenkonzentration im Zentrum Damit werden die Flugstabilität und die Agilität des Hubschraubers erhöht. Auch die kompakten Abmessungen tragen dazu bei.

The concept of the featured helicopter 1 with camera 5 also offers flight dynamics advantages:

• • The lifting units are evenly loaded Due to the central positioning of the camera, the overall center of gravity of the helicopter is also there. Each lifting unit therefore contributes in equal parts to the total drive. The power reserve of the lifting units is the same.
• • No disturbing roll and pitch moments when the helicopter is accelerating horizontally. The center of lift (point of application of the resulting buoyancy force) and the center of gravity (point of application of the resulting inertia force) are approximately in one height level. This results in a neutral flight behavior. With a larger, vertical distance of these points to each other (for example, because of a very deep-mounted, relatively heavy camera) roll or pitch moments would occur when horizontal acceleration or deceleration of the helicopter, which can bring considerable unrest in the aircraft and it Make extreme case unmanageable.
• • Low mass inertia due to mass concentration in the center This increases the flight stability and agility of the helicopter. The compact dimensions also contribute to this.

The 3 to 8th show variants of the featured helicopter. In Examples 2 and 3, the rotors are on the longitudinal and transverse axes of the helicopter, in Examples 1 and 4 between the axles. The front rotors 3 are in the examples 1 to 3 above the opening range of the camera 5 arranged (height graduation of the rotors), in Example 4 right and left of it (greater lateral distance of the rotors). Common to all the examples is the free camera view without annoying helicopter components in the image when the camera is near the center of the buoyancy (distance less than 10% of d).

In some cases, the dimensions of the presented helicopters can be further reduced. In example 3 ( 5 and 6 ) can z. B. the center distances of each opposing rotors are further significantly reduced without adjacent rotors collide with each other. The height offset makes it possible.

1

helicopter

2

lifting unit

3

rotor

4

electric motor

5

camera

7

rotor blade

8th

shoring

10

control unit

Claims (11)

Helicopter ( 1 ) with three or more lifting units ( 2 ) each having at least one rotor ( 3 ) and at least one rotor ( 3 ) driving electric motor ( 4 ), as well as with at least one camera ( 5 ), wherein at least one rotor ( 3 ) in front of the camera ( 5 ) is arranged, the rotor circling surface in hover position of the helicopter ( 1 ) at approximately horizontal shooting direction of the camera ( 5 ) completely above, below or to the side of the opening area of the camera ( 5 ) and the rotor circuit surfaces of all rotors ( 3 ) of the helicopter ( 1 ) outside the opening area of the camera ( 5 ) lie. Helicopter ( 1 ) according to claim 1, characterized in that a rotor ( 3 ) in front of the camera ( 5 in hover position by at least about 20% of the mean rotor diameter of the rotors ( 3 ) above another rotor ( 3 ) lies. Helicopter ( 1 ) according to claim 1 or 2, characterized in that two rotors ( 3 ) in front of the camera ( 5 are arranged in hover position by at least about 20% of the average rotor diameter of the rotors ( 3 ) above another rotor ( 3 ) lie. Helicopter ( 1 ) according to one of claims 1 to 3, characterized in that two rotors ( 3 ) in front of the camera ( 5 ) whose rotor circuit areas on the right and left of the opening area of the camera ( 5 ) lie. Helicopter ( 1 ) according to one of claims 1 to 4, characterized in that the mass of the camera ( 5 ) more than approximately 20% of the departure mass of the helicopter ( 1 ) is. Helicopter ( 1 ) according to one of claims 1 to 5, characterized in that the camera ( 5 ) has an opening angle between about 20 degrees and about 45 degrees. Helicopter ( 1 ) according to one of claims 1 to 6, characterized in that the camera ( 5 ) is provided with facilities for storing images. Helicopter ( 1 ) according to one of claims 1 to 7, characterized in that the center of gravity of the camera ( 5 ) by less than approximately 50% of the average rotor diameter of the rotors ( 3 ) from the center of gravity of the complete helicopter ( 1 ) is removed. Helicopter ( 1 ) according to one of claims 1 to 8, characterized in that the center of gravity of the camera ( 5 ) by less than approximately 50% of the average rotor diameter of the rotors ( 3 ) from the center of lift of the helicopter ( 1 ) is removed. Helicopter ( 1 ) according to one of claims 1 to 9, characterized in that the helicopter ( 1 ) has a take-off mass of less than about 5 kg, preferably less than about 1 kg. Helicopter ( 1 ) according to one of claims 1 to 10, characterized in that the overall dimensions of the helicopter ( 1 ) are below about 2 m, preferably below about 1.2 m.