Sensor orientation for environmental error reduction
A processor of an apparatus in one example makes a determination of an environmental characteristic based on a plurality of concomitant values that correspond to the environmental characteristic. A plurality of sensors obtains the plurality of concomitant values. The plurality of sensors configured in a plurality of orientations.
1 . An apparatus, comprising:
a plurality of sensors that obtain a plurality of concomitant values indicative of an environmental characteristic, the plurality of sensors being configured respectively in a plurality of orientations; and
a processor having a plurality of inputs for receiving the plurality of concomitant values and having an output that provides a determination of the environmental characteristic;.
2 . The apparatus of claim 1 , wherein each sensor of the plurality of sensors lies along a common three-dimensional unit vector;
wherein the plurality of orientations comprise a first orientation and a second orientation; and
wherein the second orientation is inverted on the three-dimensional unit vector relative to the first orientation.
3 . The apparatus of claim 2 , wherein the plurality of sensors comprise electronic sensors; and
wherein at least one of the plurality of electronic sensors is coupled to a first side of a circuit board and at least one of the plurality of electronic sensors is coupled to a second side of the circuit board.
4 . The apparatus of claim 2 , wherein the environmental characteristic comprises an angular rate;
wherein the plurality of sensors comprise a first gyroscope that obtains a first value of the plurality of concomitant values and a second gyroscope that obtains a second value of the plurality of concomitant values; and
wherein the processor determines a difference between the first value and the second value such that an error term of the angular rate that corresponds to a second order gravity term is reduced.
5 . The apparatus of claim 1 , wherein each sensor of the plurality of sensors is associated with a three-dimensional unit vector;
wherein axes of the plurality of sensors lie along a common three-dimensional unit vector;
wherein the plurality of orientations comprise a first orientation and a second orientation; and
wherein the second orientation is rotated about the three-dimensional unit vector relative to the first orientation.
6 . The apparatus of claim 5 , wherein the second orientation is rotated about the three-dimensional unit vector by one of 0, 45, 90, 135, 180, 225, 270, or 315 degrees relative to the first orientation.
7 . The apparatus of claim 5 , wherein the environmental characteristic comprises an angular rate;
wherein the plurality of sensors comprise a first gyroscope that obtains a first value of the plurality of concomitant values and a second gyroscope that obtains a second value of the plurality of concomitant values;
wherein the first gyroscope has the first orientation;
wherein the second gyroscope has the second orientation;
wherein the second orientation is rotated about the three-dimensional unit vector by 180 degrees relative to the first orientation; and
wherein the processor determines a difference between the first value and the second value such that error terms of the angular rate that corresponds to a first order gravity term and/or third order gravity term is reduced.
8 . The apparatus of claim 1 , wherein the plurality of sensors comprise at least one of gyroscopes and accelerometers; and
wherein the environmental characteristic comprises at least one of an angular rate and an angular acceleration.
9 . An apparatus, comprising:
a plurality of sensors that obtain a plurality of concomitant values indicative of an environmental characteristic, the plurality of sensors being configured respectively in a plurality of orientations; and
a processor having a plurality of inputs for receiving the plurality of concomitant values and having an output that provides a determination of the environmental characteristic
each sensor of the plurality of sensors associated with a three-dimensional unit vector, axes of the plurality of sensors lying along a common three-dimensional unit vector;
the plurality of sensors being configured in at least one opposing orientation set;
each opposing orientation set comprising first and second sensors; and
the second sensor having an orientation that is rotated about the three-dimensional unit vector by 180 degrees and/or inverted on the three-dimensional unit vector relative to an orientation of the first sensor.
10 . The apparatus of claim 9 , wherein each opposing orientation set of the at least one opposing orientation set comprises the first sensor, the second sensor, a third sensor, and a fourth sensor;
wherein the second sensor has an orientation that is rotated about the three-dimensional unit vector by 180 degrees relative to the orientation of the first sensor;
wherein the third sensor has an orientation that is inverted on the three-dimensional unit vector relative to the orientation of the first sensor; and
wherein the fourth sensor has an orientation that is inverted on the three-dimensional unit vector relative to the orientation of the first sensor and rotated about the three-dimensional unit vector by 180 degrees relative to the orientation of the first sensor.
11 . The apparatus of claim 10 , wherein the at least one opposing orientation set comprises first, second, third, and fourth opposing orientation sets;
wherein the first sensor of the second opposing orientation set has an orientation that is rotated about the three-dimensional unit vector by 45 degrees relative to the first sensor of the first opposing orientation set;
wherein the first sensor of the third opposing orientation set has an orientation that is rotated about the three-dimensional unit vector by 90 degrees relative to the first sensor of the first opposing orientation set; and
wherein the first sensor of the fourth opposing orientation set has an orientation that is rotated about the three-dimensional unit vector by 135 degrees relative to the first sensor of the first opposing orientation set.
12 . The apparatus of claim 9 , wherein the at least one opposing orientation set comprise a plurality of opposing orientation sets;
wherein each opposing orientation set of the plurality of opposing orientation sets provides a value of the environmental characteristic to the processor; and
wherein the processor determines an average of the values of the environmental characteristic.
13 . A method, comprising:
obtaining, via a plurality of sensors, a plurality of concomitant values indicative of an environmental characteristic, the plurality of sensors being configured respectively in a plurality of orientations, each sensor of the plurality of sensors associated with a three-dimensional unit vector, axes of the plurality of sensors lying along a common three-dimensional unit vector, the plurality of sensors being configured in at least one opposing orientation set, with each opposing orientation set comprising first and second sensors, the second sensor having an orientation that is rotated about the three-dimensional unit vector by 180 degrees and/or inverted on the three-dimensional unit vector relative to an orientation of the first sensor; and
calculating from the plurality of concomitant values at least a single value indicative of the environmental characteristic.
14 . The method of claim 13 , wherein each opposing orientation set of the at least one opposing orientation set comprises the first sensor, the second sensor, a third sensor, and a fourth sensor;
wherein the second sensor has an orientation that is rotated about the three-dimensional unit vector by 180 degrees relative to the orientation of the first sensor;
wherein the third sensor has an orientation that is inverted on the three-dimensional unit vector relative to the orientation of the first sensor; and
wherein the fourth sensor has an orientation that is inverted on the three-dimensional unit vector relative to the orientation of the first sensor and rotated about the three-dimensional unit vector by 180 degrees relative to the orientation of the first sensor.
15 . The method of claim 14 , wherein the at least one opposing orientation set comprises first, second, third, and fourth opposing orientation sets;
wherein the first sensor of the second opposing orientation set has an orientation that is rotated about the three-dimensional unit vector by 45 degrees relative to the first sensor of the first opposing orientation set;
wherein the first sensor of the third opposing orientation set has an orientation that is rotated about the three-dimensional unit vector by 90 degrees relative to the first sensor of the first opposing orientation set; and
wherein the first sensor of the fourth opposing orientation set has an orientation that is rotated about the three-dimensional unit vector by 135 degrees relative to the first sensor of the first opposing orientation set.
16 . The method of claim 13 , wherein the at least one opposing orientation set comprise a plurality of opposing orientation sets;
wherein each opposing orientation set of the plurality of opposing orientation sets provides a value of the environmental characteristic to the processor; and
wherein the processor determines an average of the values of the environmental characteristic.