Presentation supporting device

• US 5,874,941 A
• Filed: 09/27/1995
• Issued: 02/23/1999
• Est. Priority Date: 09/28/1994
• Status: Expired due to Term

• Current Assignee: Rakuten, Inc. (Rakuten Group, Inc.)
• Original Assignee: NEC Corporation
• Inventors: Yamada, Keizo
• Primary Examiner(s): WU, XIAO MIN
• Application Number:
  US08/534,299
• Time in Patent Office: 1,245 Days
• Field of Search: 345/163, 345/166, 345/157, 345/158, 345/156, 345/159, 345/161, 345/162, 345/169, 345/145, 345/146, 340/988
• US Class Current: 345/157
• CPC Class Codes: G06F 3/0346 with detection of the device orientation or free movement in a 3D space, e.g. 3D mice, 6-DOF [six degrees of freedom] pointers using gyroscopes, accelerometers or tilt-sensors

Abstract

A presentation supporting device having excellent operability and adaptability to oral presentations in a computer multimedia environment. First and second accelerometers detect first and second acceleration of gravity resulting from inclinations in first and second sensitivity axis directions perpendicular to each other to output first and second acceleration signals, and first and second signal processors process the input first and second acceleration signals to output cursor moving control signals for controlling moving speeds and moving directions in the first and second coordinate axis directions of a cursor on a computer display screen in response to voltage values and polarities of the first and second acceleration signals.

Claims

1. A presentation supporting device comprising:

first and second discrete accelerometers for individually detecting first and second accelerations of gravity resulting from inclinations in first and second sensitivity axis directions perpendicular to each other to output first and second acceleration signals; and

first and second discrete signal processors, individually associated with the first and second accelerometers, for processing input first and second acceleration signals to output cursor moving control signals for controlling moving speeds and moving directions in the first and second coordinate axis directions of a cursor on a computer display screen in response to voltage values and polarities of the first and second acceleration signals, wherein each of the first and second signal processors includes;

an amplifier circuit for amplifying the acceleration signal to output an amplified acceleration signal;

an absolute value circuit for converting the amplified acceleration signal to an absolute value having a voltage value of a positive polarity with respect to a predetermined first reference value to output an absolute value signal; and

a first threshold circuit for comparing the amplified acceleration signal with the first reference value to output a phase switch signal corresponding to the comparison result.

2. The presentation supporting device as claimed in claim 1, wherein each of the first and second accelerometers includes:

a cantilevered beam mounted at its first end and having a mass on its free end; and

a strain gauge attached near the first end of the cantilevered beam,

wherein each accelerometer detects distortion of the cantilevered beam by using the strain gauge to measure the acceleration corresponding to a given stress caused by the mass.

3. The presentation supporting device as claimed in claim 1, further comprising a differentiation circuit for differentiating the acceleration signal to output a differentiated acceleration signal proportional to rotational speed of rotatory motion generating the inclination.

4. The presentation supporting device as claimed in claim 1, further comprising a differential amplifier,

wherein the first accelerometer includes first and second rotational accelerometers which are arranged in opposite sides around an imaginary axis of rotation so that their sensitivity axes face to opposite directions, and output first and second rotational acceleration signals,

the differential amplifier calculating a difference between the first and second rotational acceleration signals to output a differential rotational acceleration signal.

5. The presentation supporting device as claimed in claim 1, further comprising a reset push button switch for supplying a reset instruction for setting the cursor to an initial position predetermined on the computer display screen.

6. The presentation supporting device as claimed in claim 1, further comprising paging push button switches for instructing page forward and return of the computer display screen.

7. The presentation supporting device as claimed in claim 1, further comprising a radio signal conversion circuit for coding the cursor moving control signals to obtain coded cursor moving control signals and converting the coded cursor moving control signals to radio signals of a predetermined modulation system.

8. A presentation supporting device comprising:

first and second discrete accelerometers for individually detecting first and second accelerations of gravity resulting from inclinations in first and second sensitivity axis directions perpendicular to each other to output first and second acceleration signals; and

first and second discrete signal processors, individually associated with the first and second accelerometers, for processing input first and second acceleration signals to output cursor moving control signals for controlling moving speeds and moving directions in the first and second coordinate axis directions of a cursor on a computer display screen in response to voltage values and polarities of the first and second acceleration signals, wherein each of the first and second signal processors includes;

an amplifier circuit for amplifying the acceleration signal to output an amplified acceleration signal;

an absolute value circuit for converting the amplified acceleration signal to an absolute value having a voltage value of a positive polarity with respect to a predetermined first reference value to output an absolute value signal;

a first threshold circuit for comparing the amplified acceleration signal with the first reference value to output a phase switch signal corresponding to the comparison result;

a voltage frequency conversion circuit for converting the absolute value signal to a pulse signal of a frequency corresponding to the voltage value;

an emulation waveform generator circuit for converting the pulse signal to first and second emulation waveforms as control signals for moving the cursor; and

phase switch circuit for selecting either a first or second emulation waveform in response to the phase switch signal supplied to output the cursor moving control signal.

9. The presentation supporting device as claimed in claim 8, wherein each signal processor further includes a second threshold circuit for comparing the absolute value signal with a predetermined second reference value to output an enable signal for allowing the cursor moving control signal to output only when the absolute value signal is larger than the second reference value.

10. The presentation supporting device as claimed in claim 9, wherein the voltage frequency conversion circuit includes a voltage-controlled oscillator circuit which is either operated or stopped in response to either a first or second level of the enable signal supplied.

11. The presentation supporting device as claimed in claim 8, wherein each signal processor further includes a first switch circuit for allowing the first and second emulation waveforms to either pass or stop in response to either a first or second level of the enable signal supplied.

12. The presentation supporting device as claimed in claim 8, further comprising a radio signal conversion circuit for coding the cursor moving control signals to obtain coded cursor moving control signals and converting the coded cursor moving control signals to radio signals of a predetermined modulation system.

13. A presentation supporting device comprising:

first and second accelerometers for detecting first and second accelerations and for out-putting first and second acceleration signals each having a voltage value;

first and second signal processors, connected to said first and second accelerometers respectively, for processing input first and second acceleration signals to output cursor moving control signals;

wherein at least one of said first and second signal processors includes a voltage to frequency conversion circuit for converting the acceleration signal voltage value to a pulse signal of a frequency corresponding to the voltage value, wherein said at least one of said first and second signal processors further includes an emulation waveform generator circuit for converting the pulse signal to first and second emulation waveforms as control signals for moving the cursor; and

wherein said at least one of said first and second signal processors further includes a first threshold circuit for comparing the acceleration signal with a first reference value to output a phase switch signal corresponding to the comparison result.

14. The presentation supporting device as in claim 13, wherein said at least one of said first and second signal processors further includes a phase switch circuit for selecting either a first or second emulation waveform in response to the phase switch signal supplied to output the cursor moving control signal.

15. The presentation supporting device as in claim 14, wherein said at least one of said first and second signal processors further includes an amplifier circuit for amplifying the acceleration signal to output an amplified acceleration signal, and an absolute value circuit for converting the amplified acceleration signal to an absolute value having a voltage value of a positive polarity with respect to a predetermined first reference value to output an absolute value signal;

wherein said voltage to frequency conversion circuit converts the absolute value signal to a pulse signal of a frequency corresponding to the voltage value.