Triaxial angular rate and acceleration sensor

• US 6,463,802 B2
• Filed: 02/15/2001
• Issued: 10/15/2002
• Est. Priority Date: 02/08/1991
• Status: Expired due to Fees

• Current Assignee: Rand H. Hulsing II
• Original Assignee: Rand H. Hulsing II
• Inventors: Hulsing, Rand H. II
• Primary Examiner(s): CHAPMAN JR, JOHN E
• Application Number:
  US09/788,166
• Publication Number:
  US 20010042405A1
• Time in Patent Office: 607 Days
• Field of Search: 735/040.4, 735/041.2, 735/10
• US Class Current: 73/504.04
• CPC Class Codes: F02G 1/044 having at least two working members, e.g. pistons, delivering power output
• CPC Class Codes: F02G 1/0445 Engine plants with combined cycles, e.g. Vuilleumier
• CPC Class Codes: F16L 37/24 in which the connection is made by inserting one member axially into the other and rotating it to a limited extent, e.g. with bayonet action
• CPC Class Codes: G01C 19/56 Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces
• CPC Class Codes: G01C 19/5719 using planar vibrating masses driven in a translation vibration along an axis
• CPC Class Codes: G01C 19/574 the devices having two sensing masses in anti-phase motion
• CPC Class Codes: G01P 15/0802 Details
• CPC Class Codes: G01P 15/097 by vibratory elements
• CPC Class Codes: G01P 15/18 in two or more dimensions
• CPC Class Codes: G01P 2015/0828 the mass being of the paddle type being suspended at one of its longitudinal ends

Abstract

A triaxial sensor substrate is adapted for use in measuring the acceleration and angular rate of a moving body along three orthogonal axes. The triaxial sensor substrate includes three individual sensors that are arranged in the plane of the substrate at an angle of 120 degrees with respect to one another. Each sensor is formed from two accelerometers having their sensing axes canted at an angle with respect to the plane of the substrate and further being directed in opposite directions. The rate sensing axes thus lie along three orthogonal axes.

In order to reduce or eliminate angular acceleration sensitivity, a two substrate configuration may be used. Each substrate includes three accelerometers that are arranged in the plane of the substrate at an angle of 120 degrees with respect to one another. The sensing axes of the accelerometers of the first substrate are canted at an angle with respect to the plane of the first substrate toward the central portion thereof so that they lie along three skewed axes. Similarly, the sensing axes of the accelerometers of the second substrate are canted at an angle with respect to the plane of the second substrate away from the central portion thereof so that they lie along same three but oppositely directed axes. The sensing axes of the first and second substrates are aligned to prevent angular acceleration sensitivity.

Claims

1. A generally planar substrate adapted for use in a triaxial angular rate and acceleration sensor comprising:

central hub;

a first set of coplanar accelerometers formed in said substrate, each of said first set of accelerometers having a sensing axis canted at an angle with respect to the plane of said substrate, said first set of accelerometers being arranged in the plane of said substrate to place said sensing axes of said first set of accelerometers skewed to one another;

a second set of coplanar accelerometers formed in said substrate, each of said second set of accelerometers having a sensing axis canted at an angle with respect to the plane of said substrate, said second set of accelerometers being arranged in the plane of said substrate to place said sensing axes of said second set of accelerometers skewed to one another, each of said second set of accelerometers being paired with a corresponding accelerometer of said first set accelerometers, corresponding accelerometer pairs having sensed axes that are parallel or anti-parallel;

linking means respectively associated with each corresponding accelerometer pair for connecting each accelerometer of each corresponding accelerometer pair together so that a dither motion on one accelerometer of said corresponding accelerometer pair creates an opposite dither motion on the other accelerometer of said corresponding accelerometer pair; and

a radial hub member respectively associated with each of said corresponding accelerometer pairs, each of said radial hub members connecting the respective linking means to said central hub.

2. A generally planar substrate adapted for use in a triaxial angular rate and acceleration sensor comprising:

a main frame;

a first set of coplanar accelerometers formed in said substrate, each of said first set of accelerometers having a sensing axis canted at an angle with respect to the plane of said substrate, said first set of accelerometers being arranged in the plane of said substrate to place said sensing axes of said first set of accelerometers skewed to one another;

a second set of coplanar accelerometers formed in said substrate, each of said second set of acclerometers having a sensing axis canted at an angle with respect to the plane of said substrate, said second set of accelerometers being arranged in the plane of said substrate to place said sensing axes of said second set of accelerometers skewed to one another, each of said second set of accelerometers being paired with a corresponding accelerometers of said first set of accelerometers, corresponding accelerometer pairs having sensed axes that are parallel or anti-parallel;

a hub having a plurality of arms, each arm of said plurality of arms being associated with a respective corresponding accelerometer pair;

a plurality of spokes connecting said hub to said main frame, said spokes providing means for connecting said first and second set of accelerometers to said main frame; and

linking means respectively connected to each arm of said hub for connecting each accelerometer of said corresponding accelerometer pair together so that a dither motion on one accelerometer of said corresponding accelerometer pair creates an opposite dither motion on the other accelerometer of said corresponding accelerometer pair.

3. A generally planar substrate adapted for use in a triaxial angular rate and acceleration sensor comprising:

a first set of coplanar accelerometers formed in said substrate, each of said first set of accelerometers having a sensing axis canted at an angle with respect to the plane of said substrate, said first set of accelerometers being arranged in the plane of said substrate to place said sensing axes of said first set of accelerometers skewed to one another;

a second set of coplanar accelerometers formed in said substrate, each of said second set of acclerometers having a sensing axis canted at an angle with respect to the plane of said substrate, said second set of accelerometers being arranged in the plane of said substrate to place said sensing axes of said second set of accelerometers skewed to one another, each of said second set of accelerometers being paired with a corresponding accelerometers of said first set of accelerometers, corresponding accelerometer pairs having sensed axes that are parallel or anti-parallel;

a hub in the form of an equilateral triangle, each side of said triangle being attached to a corresponding accelerometer pair by a plurality of parallel flexures, said hub having an arm extending from each side of said equilateral triangle; and

linking frame means respectively connected to each arm of said hub for connecting each accelerometer of said accelerometer pair together so that a dither motion on one accelerometer of said corresponding accelerometer pair creates an opposite dither motion on the other accelerometer of said corresponding accelerometer pair.