Abstract:
The invention describes a microaircraft, which can be associated for instance to a cellular phone, provided with at least four microrotors actuated with compressed fluid or by ring-shaped electric motors.

Description:
SUMMARY OF THE INVENTION  
       [0001]     The present invention relates to a microaircraft comprising a basically flat body having at least four ring-shaped microrotors, basically co-planar and arranged on the vertices of a quadrilateral, motor means for controlling said microrotors and an electronic microcontroller for controlling said motor means.  
         [0002]     In a preferred embodiment, the aforesaid microrotors are compressed air turbines and the aforesaid motor means comprise a combustion microchamber for a nano-particle fuel and one or more nozzles associated to each microturbine for directing onto the latter one or more shock fronts generated inside the combustion microchamber.  
         [0003]     In an alternative embodiment, the motor means are made up of a ring-shaped electric motor for each of the micromotors, each microrotor constituting the rotor of a corresponding electric motor.  
         [0004]     The invention also relates to a cellular phone to which a microaircraft as referred to above is connected in a removable way. The cellular phone is equipped with means for remote control of the air-craft. Preferably, the microaircraft is provided with multimedia means, such as for instance a miniature camera and a microphone, and can therefore transmit audio and video messages to the guest mobile phone or also to other cellular systems and Internet networks.  
         [0005]     The control means of the four microrotors of the microaircraft are designed to control said microrotors independently from one another or in pairs. Preferably, the microaircraft is controlled by generating a clockwise rotation on the two ring-shaped microturbines placed on two opposite vertices of the quadrilateral, and a counter-clockwise rotation on the other two microturbines. The aircraft has four degrees of freedom. By changing simultaneously or differentially the speed of the microturbines, it is possible to obtain a vertical motion (upwards and downwards), a lateral motion (right or left), a horizontal motion (forwards and backwards) or a rotation around a yaw axis.  
         [0006]     The vertical motion is controlled by increasing or decreasing simultaneously the power of all four microturbines. The lateral motion is controlled by increasing the power of two turbines on the same side of the quadrilateral with respect to the other two. For instance, by increasing the speed of the turbines on the left the aircraft shifts towards the right. In the same manner, a power increase of the two back or front turbines causes a forward or backward motion, respectively. The fourth degree of freedom is controlled by the induced moment generated by rotor resistance. This moment acts in the opposite direction with respect to rotor rotation. In order to eliminate aircraft yaw, the sum of all induced moments should be zero. However, if a set of rotors, for instance those turning clockwise, arranged on the vertices of the quadrilateral, increases its rotational speed, the resulting induced moment will generate a counter-clockwise rotation of the aircraft.  
         [0007]     In the specific case in which propulsion is obtained with electric motors, in a preferred embodiment the microaircraft uses commercially available thin film batteries or microfuel cells. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]     Further characteristics and advantages of the invention shall be evident from the following description with reference to the accompanying drawings, provided as mere non-limiting examples, in which:  
         [0009]      FIG. 1  is a perspective front view of a cellular phone-microaircraft assembly according to the invention, in disassembled condition,  
         [0010]      FIG. 2  is a perspective rear view of the assembly of  FIG. 1 ,  
         [0011]      FIG. 3  is a magnified, partially sectioned perspective view of the microaircraft belonging to the assembly of  FIGS. 1, 2 ,  
         [0012]      FIG. 3A  shows a variant,  
         [0013]      FIG. 4  is a diagram showing the control criterion applied to the four microrotors of the microaircraft,  
         [0014]      FIGS. 5, 6  are perspective views of possible embodiments of each microrotor, and  
         [0015]      FIG. 7  is a block diagram of the control system of the microaircraft according to the invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0016]     With reference to  FIGS. 1, 2 , number  1  globally refers to a microcellular phone provided with means for the removable connection of a microaircraft  2 . The third generation of cellular phones, after analogical TACS generation and digital GSM generation, can reach transmission rates up to 2 megabits per second, i.e. 200 times more with respect to the limits of GSM system, thus enabling high definition audio and video transmissions. The success of said standard as global mobile communication standard allows a virtual connectivity worldwide. The microaircraft  2  comprises, as shown in  FIG. 3 , a basically flat body  3  with four microrotors  4  arranged on the vertices of a quadrilateral, basically co-planar one to the other. A compressed gas (or air) tank  5  supplied through a valve  6  is defined inside the body  3 . Each microrotor  4  is associated to one or more nozzles  7  connected to a combustion microchamber  8 , in which a nano-particle fuel generates a microcombustion causing one or more shock fronts for controlling each microrotor. The nozzles  7  can be arranged on the two opposite ends of the same combustion microchamber placed between two adjacent turbines ( FIG. 3A ), so as to control both turbines. The system for obtaining a pulsed jet can be of “valveless” or “detonation” type. The rotor of each microturbine can be of “magnetic lift” type.  
         [0017]     In  FIG. 4  the microrotors  4  are referred to in short with AS (front left), AD (front right), PS (rear left) and PD (rear right). The two rotor pairs AS, PD and AD, PS are rotated in opposite directions, as shown in  FIG. 4 , so as to ensure the reciprocal cancellation of yaw moments. As already mentioned above, the vertical, lateral, horizontal motion and a yaw rotation are obtained by means of a selective control of the rotation speed of the four microrotors.  
         [0018]      FIGS. 5, 6  are perspective views of two possible embodiments of each microrotor  4 .  
         [0019]     According to an alternative embodiment, each rotor  4  is the rotor arranged inside the ring-shaped stator of a ring-shaped electric motor.  
         [0020]     The body  3  of the microaircraft houses an electronic microcontroller  5 , which communicates at a distance with the cellular phone  1 . Multimedia means are further arranged on board the microaircraft, such as a miniature camera, a microphone or various sensors transmitting audio and video messages to the guest mobile phone or to other cellular systems or Internet networks.  
         [0021]      FIG. 7  shows the structure of the control system in which two main elements can be identified, i.e. the microaircraft  2  and the base station. The microaircraft  2  comprises the four microrotors  4  with their control motors  7  controlled by means of an electronic speed controller  8  by a microprocessor  5 . The latter communicates by means of sensors  20  and a GPS antenna  21  at radio frequency with the mobile phone or an Internet station, which send control data, whereas the aircraft transmits audio-video data. Said result is achieved by means of one or more miniature cameras  22  connected through a video transmitter  23  and an antenna  24  with the antenna  25  of a video base receiver  26 . The miniature cameras (CCD or CMOS) are also designed as dynamic view sensors for self-movement. Control signals are sent by the control station  27  or by the mobile phone by means of a R/C transmitter  28  and a transmitting antenna  29 , so as to be received by means of an antenna  30  by a data receiver  31  receiving a power line  32  and transmitting to the microprocessor  5  on a four-channel line  33 . The microaircraft is eventually associated to a battery assembly  34 .  
         [0022]     The microprocessor is the core of the microaircraft. It receives input signals from on-board sensors and video information from cameras and sends output signals for electronic (nano-particle) speed controllers of the microturborotors. As was already said, in an alternative version with respect to compressed air motors, said motors can be ring-shaped electric motors. Anyhow, a preferred characteristic of the invention is the use of compressed air turborotors supercharged by means of microcombustions.  
         [0023]     A self-charge function of turborotors and of ring-shaped electric motors can be provided by means of wind energy.  
         [0024]     As was already said, a thin film battery or a microfuel cell can be used.  
         [0025]     Obviously, though the basic idea of the invention remains the same, construction details and embodiments can widely vary with respect to what has been described and shown by mere way of example, however without leaving the framework of the present invention.