Method for capacitative object recognition in motor vehicles
First Claim
1. A method for capacitive detection of an object in a vehicle having first and second condenser electrodes that are excited by an alternating voltage, the presence of an object being detected by a change of the total capacity of a condenser, said method comprising:
- exciting the first and second electrodes with separate oppositely phased alternating voltages, whereby alternating currents in feed lines of the two electrodes are added up; and
detecting at least one of presence, size and position of an object adjacent said electrodes based upon determined impedance of said first and second electrodes.
1 Assignment
0 Petitions
Accused Products
Abstract
A capacitive object detection system for a vehicle has first and second capacitive electrodes embedded in the vehicle seat. The two electrodes are excited by oppositely phased alternating voltages, which are adjusted by a controller such that the resulting alternating currents in their respective feed lines are substantially equal and oppositely phased. The presence, size and location of an adjacent object is then determined based on an analysis of the impedances of the first and second electrodes.
27 Citations
15 Claims
-
1. A method for capacitive detection of an object in a vehicle having first and second condenser electrodes that are excited by an alternating voltage, the presence of an object being detected by a change of the total capacity of a condenser, said method comprising:
-
exciting the first and second electrodes with separate oppositely phased alternating voltages, whereby alternating currents in feed lines of the two electrodes are added up; and
detecting at least one of presence, size and position of an object adjacent said electrodes based upon determined impedance of said first and second electrodes. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. Apparatus for detecting an object in an automobile, comprising:
-
first and second electrodes embedded in a surface of said automobile adjacent a location where an object is to be detected;
an alternating voltage source connected to supply oppositely phased first and second alternating voltages to said first and second electrodes, respectively; and
a controller for adjusting said first and second alternating voltages such that a sum of alternating currents in feed lines of the first and second electrodes is substantially equal to zero;
wherein said controller determines at least one of presence, size and position of an object in said location, based on a determination of a.c. impedances of said first and second electrodes. - View Dependent Claims (11, 12, 13, 14, 15)
-
Specification