Sound System That Determines the Position of an External Sound Source and Points a Directional Microphone/Speaker Towards It

1. Field of Invention

This invention relates to drive-up ordering stations in fast food restraints. Specifically to. the sound system of remote ordering by sound speaker & microphone connection.

2. Prior Art

Doi (U.S. Pat. No. 4,037,052) has a paraboloid pickup (microphone) assembly. Srour etal, (U.S. Pat. No. 4,964,100) has a similar acoustical detector with paraboloid reflector. Zlevor (U.S. Pat. No. 4,264,790) shows a portable directional microphone that has a paraboloid reflector. All of these systems do not have a bidirectional communication of the paraboloid reflector.

Saylors (U.S. Pat. No. 4,313,183) teaches a way to determine distance by sonar methods. However, it does not require triangulation technique.

The object of this invention is make two-way sound communication require less effort from the human elements. That is, this sound system makes human communication clearer to understand one another. Conventional microphone & speaker systems use wide angle dispersion of sound for communication. This system uses a paraboloid reflector to narrow the angle and localize the communication.

The present invention is a sound system that can triangulate an external sound source's position and then to point a paraboloid microphone/speaker towards that position. This would allow for two people to have two-way communication between the external sound source and the person who is linked to the paraboloid microphone/speaker.

1 Sound source in vehicle

1A Sound waves in air

1B Computer

1C Menu ordering board

2 Sound receiver sensors

2A Origin of coordinate system

3 Paraboloid microphone/speaker

3A Paraboloid reflector surface

3B Microphone & Speaker combination

3BA Communication wire

3C Positioning motors of reflector surface

FIG. 1 shows the working model of the system. Shown is a car with a person ordering by sound into a menu board.

The menu board has the sound system of sound sensors and a paraboloid microphone/speaker.

FIG. 2A illustrates the geometry of the three sound sensors and the triangulation principle.

FIG. 2B shows the equations necessary for determining the external sound source's position.

FIG. 3 describes the paraboloid microphone/speaker subsystem.

FIG. 4 illustrates the flow diagram for the system's computer.

FIG. 1 shows a global view of the system. A vehicle 1 drives upto a fast food drive up ordering menu board. The pressure plate in the drive way (not shown) is activiated by the vehicle's weight. As a result, the three sound sensors R1,R2 & R3 are activated. These sensors 2 report the sound intensity of the vehicle's sound source 1 to the computer 1B. That is, the sound source 1 of the driver's voice produces sound waves if that intersect the sound sensors 2 (R1,R2 & R3). An analog to digital convertor (not shown) changes the sensors 2 signals into computer language (digital). The computer calculates (see FIGS. 2A & 2B) the voice's position 1 relative to the menu board's coordinate system. After this calculation or triangulation, the paraboloid microphone/speaker 3 (see FIG. 3) is pointed, as a vector, towards the source 1. Since the paraboloid microphone/speaker 3 is bidirectional, a source person to destination person is more localized than any conventional wide angle microphone/speaker system.

FIG. 2A shows the geometry of the triangulation. A source 1 sends sound waves to the sensors 2. (r1,r2,r3) are distances from the source 1 to the sensors (R1,R2,R3) respectfully. These distances are determined by the sound intensities at R1,R2 & R3 from source 1 and sound's inverse square law for intensity vs distance. Likewise, (s1,s2,s3) are the known distances (system installation) to (R1,R2,R3) respectfully. The paraboloid microphone/speaker 3 is identical to the origin's 2A coordinate system. The vector V points from the origin 2A to the source 1.

FIG. 2B are equations of triangulation. (a) is the distance si from the sensors 2 to the origin 2A. That is, (xi,yi,zi) are the origin's coordinates from (R1,R2,R3) to origin 2A. (b) is the intensity to distance relation (ie inverse square law for sound). In an algebraic way (not shown) if sound intensity is known, distance from the source can be known. (c) is the equations of three spheres with there origins being R1,R2 & R3. That is, these equations are spheres that are displaced from the origin 2A by s1,s2 and s3. These three nonconcentric spheres will intersect at two points (atmost). One of these two points will be above ground and the other below ground. The one above will be the source 1 solution for the triangulation. (d) describes the problem statement of 3 quadratic equations (spheres) and 3 unknowns with a set of two solutions. (e) is the vector V from the origin 2A to the source 1. V is the vector that points the paraboloid microphone/speaker 3 towards the source 1 from the origin 2A (where the paraboloid microphone/speaker 3 is located).

FIG. 3 is a close up of the paraboloid microphone/speaker 3. The reflector surface 3A is a finite paraboloid surface of material that can focus, at one point, the plane waves traveling towards the axis of the paraboloid (ie a parabolic curve rotated about an axis forms a paraboloid surface). At the focus 3B is a microphone and a speaker combined into one. This allows the focus 38 to receive waves and transmit waves. The connecting wire 3BA from the microphone/speaker leads into the computer 1B and the remote person (the other two-way communication connection).

The motor 30 moves the paraboloid surface 3A with two dimensional freedom (left-right and up-down). This gives it full directional motion towards the source 1.

FIG. 4 is the flow diagram for the computer's processor 1B. From the start, the question is "Is the pressure plate active?" Or "Has a car drove up to the menu board?" If not then repeat question. If so, activate sound sensors and wait until voice contact is initiated. Next, triangulate the voice with the sound sensors R1,R2 & R3 (see FIG. 2A & 2B). The computer calculates the vector V and points the paraboloid microphone/speaker 3 towards the source by vector V. Begin communicating transaction of ordering unless interrupted or "Is the communication clear?" (or "Has the voice shifted it's position?"). If so, retriangulate source and repeat pointing paraboloid. If communication remains clear and transaction is completed, return back to first question.