| US 7,367,232 B2 | ||
| System and method for a three-axis MEMS accelerometer | ||
| Vladimir Vaganov, 129 El Porton, Los Gatos, Calif. 95032 (US); and Nickolai Belov, 118 Plazoleta, Los Gatos, Calif. 95032 (US) | ||
| Filed on Jan. 24, 2005, as Appl. No. 11/42,721. | ||
| Claims priority of provisional application 60/538638, filed on Jan. 24, 2004. | ||
| Prior Publication US 2005/0160814 A1, Jul. 28, 2005 | ||
| Int. Cl. G01P 15/12 (2006.01) | ||
| U.S. Cl. 73—514.33 | 13 Claims |
| 1. A method of determining three components of an applied inertial force with respect to an orthogonal coordinate system,
said method comprises the steps of:
providing a semiconductor sensor chip having side 1 and comprising a frame element, a proof mass element and an elastic element mechanically coupling the frame and proof mass
element;
selectively positioning only three stress-sensitive IC components integrated into three local areas of the elastic element;
orienting the orthogonal coordinate system such that X and Y axes are located in the plane of side 1 and Z axis is perpendicular to side 1;
applying a known inertial force to the sensor chip along X, Y and Z axes;
determining the matrix of offsets and matrix of sensitivities of the stress-sensitive IC components to the orthogonal components
of the known applied force;
determining three orthogonal components of the unknown applied inertial force by solving with digital processing a system
of three equations containing the three orthogonal components of the unknown applied force, matrixes of offsets and sensitivities
of the stress-sensitive IC components to orthogonal components of the known inertial force vector.
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