Orientation sensor utilizing intra-pattern property measurements

Abstract

An orientation sensor capable of generating at least one output signal indicative of a particular orientation parameter is described. The orientation sensor comprises a sensor housing defining a closed internal chamber including a first internal surface. The first internal surface supports a first electrically conductive pattern which itself forms part of a sensing arrangement. The first electrically conductive pattern includes an arrangement of electrically isolated segments in a predetermined configuration. A flowable material is contained within the internal chamber, which flowable material contacts a portion of the first internal surface dependent upon the value of the particular orientation parameter. An electrical property is measurable between the segments such that the orientation parameter can be determined using the output signal based only on the electrical property and, therefore, only on the portion of the first internal surface contacted by the flowable material. Thus, intra-pattern measurements yield the measured property without the need for conductive members distributed along the length of the chamber. A combination pitch/roll sensor is described in which a single electrically conductive pattern cooperates with the flowable material so as to produce independent electrical signals corresponding to the pitch and roll of the housing. In one aspect, first and second electrically conductive patterns are provided at opposing ends of a flowable material chamber. Use of signals from the patterns results in ratiometric cancellation of temperature error.