This invention is in the field of control systems, more particularly control systems directed to RC (remote control) of electric motor power systems in aircraft, particularly unmanned small scale model and toy helicopters, via space-transmitted energy delivering RC commands originated in the form of gestures of a user's empty hand.
Wireless RC of a moving object has been known and practiced for many years and has become highly developed as exemplified by the advent of unmanned drone aircraft. Typically, in all categories of electric control technology including wired, wireless, remote and local, a user initiates control commands via tactile electro-mechanical “hands-on” (or foot-actuated) manipulation of user-interface control devices including proportional controls such as joysticks, sliders and rotary knobs of potentiometers and variable resistors, etc., and binary digital switching controls such as keyboards, key pads, pushbuttons, toggle switches, etc.
The hobby of model aircraft has benefited greatly from advances in wireless RC development, particularly in the categories of model and toy helicopters continuing to increase in public popularity due to ergonomic innovations and improvements which contribute greatly to the convenience, safety and recreational benefits from these hobbies in addition to their educational and training value. Ongoing development efforts in the technology of toy helicopters and RC thereof continue to provide increased convenience, performance and safety at lower cost.
Further technical challenges are encountered in attempting to RC a small-scale or toy helicopter even if it is equipped with costly state-of-the-art omni-directional position-sensing automatic control technology. The need for such automation operating in conjunction with good RC capability becomes evident when attempting to RC a typical model helicopter with dual counter-rotating rotors running at equal constant speed for the desired hovering altitude and with horizontal travel controls set and held at neutral. Without position-sensing control automation, excessive erratic sway and random travel drift off station are almost inevitable, due mainly to unpredictable self-generated and/or environmental air currents aggravated by nearby buildings, walls or other objects. Accomplishing hand-gesture RC capability that simulates or at least approaches the control capabilities available to an onboard pilot poses even further heretofore unfulfilled technical challenges and needs that are hereby addressed by the present invention.
U.S. Pat. No. 2,281,928 issued Feb. 28, 1928 to Leo S. Theremin for METHODS AND APPARATUS FOR THE GENERATION OF SOUNDS, originated in Russia in 1919, teaches control of a musical instrument, e.g. regarding frequency (pitch) and loudness, from gestures of at least one empty hand in open space above control elements that make the space an electrostatic charge field of a capacitance in an oscillator circuit caused to vary in frequency from the influence of hand movements because the dielectric constant of the hand is much greater than that of the surrounding charge field medium.
U.S. Pat. No. 6,27Wang9,777 issued Aug. 21, 2001 to Goodin et al for DISPENSING CONTROL SYSTEM discloses a system for controlling operation of a device in response to the presence of a human body part, utilizing a theremin for such detecting.
U.S. Pat. No. 7,100,866 B2 to Rehkemper et al for CONTROL SYSTEM FOR A FLYING VEHICLE utilizes on on-board proximity sensor wherein the sensor element operates in a known basic binary logic mode, i.e. switching a command signal between two states (on/off) depending on the criteria of whether or not a reflected signal is received.
U.S. Pat. No. 8,639,400 B1, issued Jan. 28, 2014 to Wang for ALTITUDE CONTROL OF AN INDOOR FLYING TOY, in each of three independent claims, calls for sensing vehicle position, at least altitude, by a proximity sensor having a light beam directed from the vehicle toward a surface, and repeatedly “increasing said light intensity I”, and responding to the binary criteria “ . . . if said reflected signal is received”. by adjusting a counter rate (e.g. rotor speed). The specification at column 8, lines 3, 17, describes using a hand-held controller as a proximity sensor for “ . . . gesture mode control in which player can tilt the transmitter . . . ” relative to a reflecting surface.
No RC systems are known for controlling moving objects, particularly toy helicopters, utilizing empty-hand gestures in the manner of the present invention.
It is a primary object of the invention to enable RC of a moving object in response to gestures of an RC user's hand.
It is a further object for the RC user-interface module of the invention to be made to co-operate with a known RC processor/transmitter to form an RC system wherein the module actuates at least one RC channel thereof for hand-gesture RC of the moving object.
It is a further object to incorporate in the module at least one proximity sensor unit including an emitter element radiating an energy beam and a sensor element responsive to a reflected energy beam received from the user's hand reflecting the radiated energy beam,
The foregoing objects have been met by the present invention of an user-interface preprocessor module that co-operates with a known processor to form a control system that can remotely control a moving object in response to human hand gestures. The module includes at least one emitter element radiating energy and at least one sensor element monitoring energy reflected from a hand intercepting a portion of the radiated energy and gesturing in a manner to indicate desired control. The module sends a detected energy signal to at least one RC input channel of a known RC processor/transmitter controlling the moving object. With a toy helicopter as the moving object, a single-channel module co-operating with a processor/transmitter can enable wireless RC of rotor speed and thus vertical travel and altitude proportional to hand height, enabling takeoff, hovering and landing. Additional RC channels can be incorporated in a module for gesture RC of additional functions including horizontal travel and steering.
If the controlled object 26 is in a stationary location, link 24 can be a direct wire connection as shown; otherwise RC of moving objects typically requires link 24 to be a wireless link including a transmitter at the output of processor 22 radiating, typically at RF (radio frequency), to a compatible receiver at the remote moving location of the controlled object 26. (see
Emitter element 12 is typically an LED (light-emitting diode) radiating at IR (infra red) frequency. Other types of emitter element could be utilized, and the operating frequency can be anywhere in a spectrum from audio, through RF and microwave to light. However, IR is preferred for its line-of-sight advantages, and LEDs are preferred for their high level of technological development, reliability and efficiency. The sensor element 18 could be any of several types of light sensitive devices including active and passive photocells, cadmium sulfide light-dependent resistors, photo voltaic cells, photo conductive strips, etc. A light-sensitive semiconductor diode or transistor, optimized to operate at the same IR frequency as the emitter element 12, offers good efficiency and reliability.
Hand gesture control actuates sensor element 18 only when the reflector (hand 16) is located within a cone-shaped working region starting from a lower limit located closely above module 10 and expanding as it extends upwardly, sized by inherent beamwidth angles of the emitter and sensor elements and any modification by lenses, apertures or nearby structure. The upper boundary of the working region is limited by the power level of energy radiated by emitter element 12 and system sensitivity which is in turn limited by background noise at the minimum signal level threshold of sensor 18.
Anywhere within this working region, energy radiated from emitter element 12 can be intercepted by a reflector such as hand 16 and reflected back down onto sensor element 18 so as to enable module 10 to produce a detected signal at node 20 from which processor 22 formulates channel command data that is relayed to control mechanisms of the controlled object 26, thusly responsive to reflector movements, i.e. gestures of the user's hand 18, in accordance with the present invention
Optionally, an optical lens could be located above sensor element 18 and/or emitter element 12 for enhancing system efficiency to increase the upper boundary height limit of the working region and/or reduce the required working power level of emitter element 12.
Moving hand 16 away from this axis within the working region will shift the “spotlight” accordingly, e.g. as indicated by circle “a”, which, encompassing sensor element 18, represents an control system condition that remains fully functional as “margin of error” tolerance. However the output of sensor element will fall to zero and proportional analog RC operation will become interrupted by displacement of the hand 16 off-axis in any direction to an extent that the off-axis “spotlight” of beam 14″ no longer encompasses sensor element 18.
Such on-off switching can be utilized in the most basic form of the invention wherein a single sensor element 18 is operated as a binary 0/1 switch providing an output of zero volts for binary “0” whenever no reflected energy is sensed, and switching the output to a detected DC output voltage for binary “1” upon receiving reflected energy. The detected DC output, whatever its voltage, is amplified if necessary and buffered to a standard voltage called for in a binary signal protocol: “1” whenever hand 16 is moved into the working region, switching to send “0” whenever hand 16 is moved sufficiently out of the working region in any direction; a horizontal gesture is typically preferred and utilized in this basic binary mode, wherein hand gestures will have no effect as long as the hand remain within the working region. An analog proportional channel can be controlled simultaneously by the same hand, but would require “dead man throttle ” capability to hold the current analog settings whenever the hand is moved/held out of the working region to send binary “1”.
Alternatively and preferably, a single-sensor module 10 as in
In an exemplary 3 channel control system, logic multiplexer 20 is designed with logic that automatically selects either sensor element 18′ or 18″, whichever is developing higher detected DC voltage, as the source for channel C to operate as the main channel providing proportional gesture-originated control in essentially the same manner as described above for a single channel module 10 (
For simple vehicle control, channel C could provide proportional throttle/velocity/motor-speed control, either as forward only, with zero (stop) at one end of the range, or forward/reverse, with zero (stop) at or offset from mid-range. Channels B and D could provide binary left/right vehicle steering (or heading) control actuated by the user moving hand 16 far enough off-axis to shift the circular reflected beam “spotlight” to location “b” or “d” as shown in
Optionally a “dead man throttle” feature could be incorporated to reset the three RC channels to neutral default settings in the event of input system failure, e.g. absence of a reflected energy beam 14″ as indicated by zero output from both sensor elements.
Additional gesture-originated control capabilities can be facilitated by additional sensor elements using various multiplexing, logic, and/or electro-optical techniques e.g. special aperture beam-shaping, optical geometry configurations and/or addition of one or more optical lenses above sensor and or emitter element(s).
In a basic illustrative embodiment directed to model and toy helicopters, the left hand 16 gesture-controls vertical travel and thus altitude via the single RC channel of module 10, while the right hand 16′ gesture-controls horizontal travel, including speed and steering, via the 3 RC channels of module 19′.
Module 10 is made and arranged to provide single-channel RC, as described above in connection with
Module 10′ is made and arranged to provide 3-channel RC, as described above in connection with
An optional “dead man throttle” feature as described above in connection with
Indoors in a room with an 8′ to 10′ ceiling, the lift force of the rotors increases considerably as the altitude is reduced approaching the floor due to the increasing reaction of the downdraft impacting the floor, the RC channel (3) altitude=controlled helicopter will tend to seek and move vertically to a hover altitude at which the lift force of the rotors (depending on their rotational velocity) is held equal to the helicopter's weight.
However, in attempting to hover in place without benefit of the control functions of channels (1) and (2), there would be a tendency to sway and drift horizontally out of place in random directions due to environmental and self-generated air current disturbances influenced by nearby walls and/or other objects. Due to environmental and self-generated air currents, etc., hovering stably and accurately in place typically requires horizontal stabilization and, in the absence of sophisticated onboard positional automatic control, will demand ongoing attention and control compensation from a pilot, either onboard or by RC. Otherwise, even if hovering altitude can be maintained, excessive swaying and horizontal drift are virtually inevitable.
In single-rotor helicopters, inherent counter-rotation of the fuselage, in reaction to the rotation of the rotor, is compensated by a tail-located vertical-plane fan controlled in speed, (optionally controlled automatically in conjunction with a gyro-compass) to cancel counter-rotation to maintain a constant desired heading, or altered in speed to allow counter-rotation for the purpose of altering heading direction. In helicopters with co-axial shafted dual stacked rotors, fuselage counter-rotation is inherently neutralized by the balance of equal rotor speeds. with the option of providing steering control by introducing a rotor speed differential that will cause the fuselage to rotate to a desired new heading direction, while holding an average of the rotor speeds that maintains the desired rotor lift.
Modules 10 and 10′ could be integrated into a single module with fixed hand-to-hand spacing, however two modules are advantageous not only for the benefit of adjustable spacing for user comfort, but also the flexibility for creating special RC systems using either module alone in other modes, e.g. sharing selected RC channel capabilities in co-operation with the known processor 22, interchanging the locations of modules 10′ and 10″ for a left-handed user, forming a 2-channel RC system with two single channel modules 10, or forming a 6-channel system with two 3 channel modules 10″.
The principle of the invention can be practiced in many other possible modes including manipulating a compact module embodiment held in one hand while directing the emitted beam 14′ either to a fixed reflecting surface such as a wall or floor, or even using the other hand as the reflector and varying the beam length by varying the hand-to-hand spacing in the manner of an accordion type musical instrument.
Multi-sensor-element module IR embodiments have the potential of gesturing to deliberately energize more than one sensor simultaneously to provide additional control channels by binary combinations, assuming appropriate optical selectivity. As shown in
To serve as processor 22, known brands are available with typically 2 to 4, 5 or 6 RC channels for standard toy helicopters controlled in various modes, e.g.:
(1) Using both hands, the left hand over one sensor element and the right hand over another sensor element, the right-hand controls the throttle of the vehicle by going up-and-down in the proximity detector beam. An upward thrust of the hand increases the throttle and a downward thrust of the hand decreases the throttle. The left-hand controls the forward motion of the helicopter, and the right and left hands together cause a turning motion of the helicopter, left or right, depending on whether the hands move left or right. On the left-hand side of the controller three sensors are in a V-type formation, one in front of the hand, one to the left, and one to the right. As the operator moves an outstretched hand forward covering the first middle sensor, this causes the helicopter to move forward. Covering the left hand sensor causes the helicopter to rotate to the left. Covering the right hand sensor causes the helicopter to rotate to the right. Covering the right hand sensor and the forward sensor at the same time with the left-hand causes the helicopter to go forward and travel to the right. As the operator covers the forward sensor and the left sensor at the same time, it causes the helicopter to go forward and travel to the left at the same time. The operator's right hand is making adjustments to the up-and-down travel of the helicopter.
(2) With the second controller type the right hand operates the same as the first type. However, the operator's hand is extended straight forward, intercepting the first beam. Raising hand about 4 inches causes the helicopter to rotate to the right. Raising the hand the next 4 inches commands the helicopter to rotate the left. Moving the hand forward covers the second detector and causes the helicopter to go forward. Moving the hand up and down can control left and right motion and then forward motion by raising the hand another ˜4 inches.
(3) With the third type of controller for 2 to 4 channel standard helicopters, all throttle and directional control is done with only the right hand. As the hand moves up the helicopter rises; as the hand is lowered the helicopter is lowered. As a hand comes up and moves forward the helicopter goes forward. As the hand rotates to the left the helicopter rotates to the left. As the hand rotates to the right the helicopter rotates to the right and so on.
Again, the vehicles could be of any type. In addition, objects that have a three dimensional range of motion could be similarly controlled in this remote manner.
All of these controllers could be situated on a belt, attached to the front to allow the operator to walk around and have mobility. Alternatively, they could be on a type of strap around the neck and so on.
The principles and spirit of the present invention can be readily applied to both full-sized and scaled-down objects, both fixed and moving, and are particularly applicable as an entertaining and intuitive way of remotely controlling model helicopters and other motion toys.
The key system performance characteristic is the proportionality, i.e. the detected DC voltage v from sensor element 18 as a function of the height h of hand 16 or other reflector above the sensor element 18 (i.e. length of reflected beam 14″). A hypothetical system as in
The invention may be embodied and practiced in other specific forms without departing from the spirit and essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, and all variations, substitutions and changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.
Benefit is claimed under 35 U.S.C. 119(e) of pending provisional application 61/920,365, filed Ser. No. 12/23/2013.