JP-7855898-B2 - Inertial sensor

JP7855898B2JP 7855898 B2JP7855898 B2JP 7855898B2JP-7855898-B2

Inventors

伊藤郁哉

Assignees

セイコーエプソン株式会社

Dates

Publication Date: 20260511
Application Date: 20220330

Claims (10)

A first sensor for detecting a first physical quantity in the first axis, A first detection circuit that performs detection processing of the first physical quantity based on the first sensor signal from the first sensor and outputs first detection information, A second sensor for detecting a second physical quantity in the second axis, A second detection circuit that performs detection processing of the second physical quantity based on the second sensor signal from the second sensor and outputs second detection information, A range setting unit that performs range setting processing, Includes, The range setting unit is, Based on the first detection information and the second detection information, the range setting process is performed to set the detection range of the first physical quantity in the first detection circuit. The first axis is the X-axis or the Y-axis, The first physical quantity is the X-axis angular velocity, which is the angular velocity around the X-axis, or the Y-axis angular velocity, which is the angular velocity around the Y-axis. The second axis is the Z-axis, The inertial sensor is characterized in that the second physical quantity is the Z-axis angular velocity, which is the angular velocity around the Z-axis .
In the inertial sensor described in claim 1 , The range setting unit is, An inertial sensor characterized by setting the detection range of the X-axis angular velocity or the Y-axis angular velocity to be reduced when the Z-axis angular velocity exceeds a threshold.
A first sensor for detecting a first physical quantity in the first axis, A first detection circuit that performs detection processing of the first physical quantity based on the first sensor signal from the first sensor and outputs first detection information, A second sensor for detecting a second physical quantity in the second axis, A second detection circuit that performs detection processing of the second physical quantity based on the second sensor signal from the second sensor and outputs second detection information, A range setting unit that performs range setting processing, Includes, The range setting unit is, Based on the first detection information and the second detection information, the range setting process is performed to set the detection range of the first physical quantity in the first detection circuit. The first axis is the Z-axis, The first physical quantity is the Z-axis angular velocity, which is the angular velocity around the Z-axis. The second axis is the X-axis or the Y-axis, The inertial sensor is characterized in that the second physical quantity is either the X-axis acceleration, which is the acceleration in the X-axis direction, or the Y-axis acceleration, which is the acceleration in the Y-axis direction .
In the inertial sensor described in claim 3 , The range setting unit is, An inertial sensor characterized by setting the detection range of the Z-axis angular velocity to be increased when the X-axis acceleration or the Y-axis acceleration exceeds a threshold.
A first sensor for detecting a first physical quantity in the first axis, A first detection circuit that performs detection processing of the first physical quantity based on the first sensor signal from the first sensor and outputs first detection information, A second sensor for detecting a second physical quantity in the second axis, A second detection circuit that performs detection processing of the second physical quantity based on the second sensor signal from the second sensor and outputs second detection information, A posture calculation unit that determines posture information of the object to be measured based on the first detection information and the second detection information, A range setting unit that performs range setting processing, Includes, The range setting unit is, An inertial sensor characterized by performing a range setting process to set the detection range of the first physical quantity in the first detection circuit based on the attitude information obtained by the attitude calculation unit .
In the inertial sensor described in claim 5 , The first axis is the X-axis or the Y-axis, The first physical quantity is the X-axis angular velocity, which is the angular velocity around the X-axis, or the Y-axis angular velocity, which is the angular velocity around the Y-axis. The attitude calculation unit, The roll angle, which is the rotation angle around the X axis, or the pitch angle, which is the rotation angle around the Y axis, is determined as the attitude information. The range setting unit is, An inertial sensor characterized by setting the detection range of the X-axis angular velocity or the Y-axis angular velocity to be reduced when the roll angle or the pitch angle exceeds a threshold.
A first sensor for detecting a first physical quantity in the first axis, A first detection circuit that performs detection processing of the first physical quantity based on the first sensor signal from the first sensor and outputs first detection information, A second sensor for detecting a second physical quantity in the second axis, A second detection circuit that performs detection processing of the second physical quantity based on the second sensor signal from the second sensor and outputs second detection information, A range setting unit that performs range setting processing, Includes, The range setting unit is, Based on the first detection information and the second detection information, the range setting process is performed to set the detection range of the first physical quantity in the first detection circuit. The first axis is the X-axis or the Y-axis, The first physical quantity is the X-axis angular velocity, which is the angular velocity around the X-axis, or the Y-axis angular velocity, which is the angular velocity around the Y-axis. The second axis is the Z-axis, The second physical quantity is the Z-axis angular velocity, which is the angular velocity around the Z-axis. The range setting unit is, An inertial sensor characterized in that , in the initial setup, the detection range for the Z-axis angular velocity is set to a size less than or equal to the detection range for the X-axis angular velocity or the Y-axis angular velocity .
In an inertial sensor according to any one of claims 1 to 4 , A third sensor for detecting a third physical quantity in the third axis, A third detection circuit that performs detection processing of the third physical quantity based on the third sensor signal from the third sensor and outputs third detection information, Includes, The range setting unit is, An inertial sensor characterized by performing a range setting process to set the detection range of the first physical quantity based on the first detection information, the second detection information, and the third detection information.
In the inertial sensor described in claim 8 , Includes a posture calculation unit that determines posture information of the object to be measured based on the first detection information, the second detection information, and the third detection information. The range setting unit is, An inertial sensor characterized by performing the range setting process based on the attitude information obtained by the attitude calculation unit.
In an inertial sensor according to any one of claims 1 to 9 , The range setting unit is, An inertial sensor characterized in that, when the first detection circuit is performing detection processing of the first physical quantity in the first detection range, and the detected value of the first detection information exceeds a first threshold within the first detection range, the detection range of the first physical quantity is set to a second detection range that is larger than the first detection range.

Description

This invention relates to inertial sensors, etc. Patent Document 1 discloses a method for changing the detection range of an inertial sensor. According to this method, the detection circuit of the inertial sensor changes the detection range by changing the voltage value per unit physical quantity based on the output signal that has passed through the filter section. Japanese Patent Publication No. 2017-173280 An example configuration of the inertial sensor of this embodiment.A diagram showing the relationship between output voltage and dynamic range.A circuit diagram showing an example of a range adjustment section.A diagram showing details of an example configuration of the inertial sensor in this embodiment.A specific example of the configuration of the inertial sensor of this embodiment.A diagram explaining Euler angles.A diagram illustrating tangential acceleration.A diagram illustrating centripetal acceleration.An example of range adjustment when applying the third embodiment.A diagram showing an example of the time evolution of angular velocity.A diagram showing an example of how acceleration changes over time.An example of range adjustment when applying the fourth embodiment.An example of range adjustment when applying the fifth embodiment. The following describes this embodiment. Note that the embodiment described below does not unduly limit the scope of the claims. Furthermore, not all of the configurations described in this embodiment are necessarily essential components. 1. Inertial Sensor The inertial sensor 1 of this embodiment will be described with reference to Figure 1. Figure 1 is a diagram showing an example of the configuration of the inertial sensor 1. The inertial sensor 1 can be implemented as, for example, a MEMS (Micro Electro Mechanical Systems) device. Note that, for the sake of explanation, not all components are shown in Figure 1 and Figures 4 and 8 described later. For example, electrode wiring, electrode terminals, etc., are omitted from the illustration as appropriate. Furthermore, the following explanation will use the case where the physical quantities detected by the inertial sensor 1 are acceleration, angular velocity, and attitude as an example, but the physical quantities are not limited to these and may be other physical quantities such as displacement, velocity, and the rate of change of angular velocity over time. Next, we will consider the motion of the device on which the inertial sensor 1 is mounted in three-dimensional space. Three-dimensional space is understood using the first axis A1, second axis A2, and third axis A3 which are perpendicular to each other. The first axis A1, second axis A2, and third axis A3 are, for example, the X axis, Y axis, and Z axis. The X and Y axes are parallel to the mounting surface on which the inertial sensor 1 is installed. The Z axis is perpendicular to the mounting surface on which the inertial sensor 1 is installed, i.e., the XY plane. Note that "perpendicular" includes not only intersections at 90°, but also intersections at angles slightly tilted from 90°. The inertial sensor 1 detects physical quantities. The inertial sensor 1 is an element that detects physical quantities such as velocity, displacement, and angular velocity, and is implemented using, for example, a MEMS (Micro Electro Mechanical Systems) device. The inertial sensor 1 of this embodiment detects physical quantities as a first physical quantity PQ1 and a second physical quantity PQ2. The first physical quantity PQ1 is, for example, acceleration, angular velocity, or attitude. Acceleration is the acceleration along each of the first axis A1, second axis A2, and third axis A3, and angular velocity is the angular velocity along each of the first axis A1, second axis A2, and third axis A3. Attitude, as explained later in Figure 6, is a physical parameter that identifies the attitude, and is a physical quantity expressed, for example, by Euler angles or quaternions. The second physical quantity PQ2 is a physical quantity other than the first physical quantity PQ1. Furthermore, as described later in "2. Second Embodiment," the inertial sensor 1 also detects physical quantities as a third physical quantity PQ3. The third physical quantity PQ3 is a physical quantity other than the first physical quantity PQ1 and the second physical quantity PQ2. As shown in Figure 1, the inertial sensor 1 of this embodiment includes a first sensor 51, a second sensor 52, a first detection circuit 61, a second detection circuit 62, a range setting unit 140, and an attitude calculation unit 150. The first sensor S1 and the second sensor 2 are sensors that detect physical quantities. Specifically, they detect acceleration or angular velocity. Acceleration is detected for the acceleration of the first axis A1, second axis A2, and third axis A3, using, for example, a capacitive accelerometer, a frequency-variable accelerometer, or a piezoresistive accelerometer. Angular velocity is detecte