Single Drive Multi-Axis Gyroscope with High Dynamic Range, High Linearity and Wide Bandwidth

• Main Authors: Faisal Iqbal, Hussamud Din, Byeungleul Lee
• Format: Article
• Language: English
• Published: MDPI AG 2019-06-01
• Series: Micromachines
• Subjects: MEMS; inertial sensor; single drive; multi-axis gyroscope; dynamic range; wide bandwidth
• Online Access: https://www.mdpi.com/2072-666X/10/6/410

This paper presents the design, fabrication, and characterization of a highly sensitive, single drive multi-axis gyroscope. The multi-axis gyroscope allows for a wide bandwidth in all three axes (X, Y, Z) and exhibits high linearity. The fabricated multi-axis gyroscope was fabricated with a structural thickness of 30 &#181;m and packaged at 100 mtorr using wafer level packaging. The fabricated multi-axis gyroscope has a small footprint of 1426 &#215; 1426 &#181;m², making it one of the smallest multi-axis gyroscopes. A custom printed circuit board (PCB) was designed for the evaluation of the multi-axis gyroscope. The experimental results demonstrate that the gyroscope has a high sensitivity of <inline-formula> <math display="inline"> <semantics> <mrow> <mn>12.56</mn> <mrow> <mtext>&nbsp;</mtext> <mi mathvariant="sans-serif">&#956;</mi> <mi mathvariant="normal">V</mi> </mrow> <mo>/</mo> <mi>dps</mi> <mo>,</mo> <mtext>&nbsp;</mtext> <mn>17.13</mn> <mrow> <mtext>&nbsp;</mtext> <mi mathvariant="sans-serif">&#956;</mi> <mi mathvariant="normal">V</mi> </mrow> <mo>/</mo> <mi>dps</mi> </mrow> </semantics> </math> </inline-formula> and <inline-formula> <math display="inline"> <semantics> <mrow> <mn>25.79</mn> <mrow> <mtext>&nbsp;</mtext> <mi mathvariant="sans-serif">&#956;</mi> <mi mathvariant="normal">V</mi> </mrow> <mo>/</mo> <mi>dps</mi> </mrow> </semantics> </math> </inline-formula> in the roll (X-sense), pitch (Y-sense) and yaw (Z-sense) modes respectively. The scale-factor non-linearity of the gyroscope is less than <inline-formula> <math display="inline"> <semantics> <mrow> <mn>0.2</mn> <mo>%</mo> </mrow> </semantics> </math> </inline-formula> for roll and pitch mode and <inline-formula> <math display="inline"> <semantics> <mrow> <mn>0.001</mn> <mo>%</mo> </mrow> </semantics> </math> </inline-formula> for the yaw mode, in the full-scale range of <inline-formula> <math display="inline"> <semantics> <mrow> <mo>&#177;</mo> <mn>1500</mn> <mrow> <mtext>&nbsp;</mtext> <mi>deg</mi> </mrow> <mo>/</mo> <mi mathvariant="normal">s</mi> </mrow> </semantics> </math> </inline-formula>. The multi-axis gyroscope demonstrates an angle random walk of <inline-formula> <math display="inline"> <semantics> <mrow> <mn>2.79</mn> <mrow> <mtext>&nbsp;</mtext> <mi>dps</mi> </mrow> <mo>/</mo> <msqrt> <mrow> <mi>Hz</mi> </mrow> </msqrt> </mrow> </semantics> </math> </inline-formula>, <inline-formula> <math display="inline"> <semantics> <mrow> <mn>2.14</mn> <mrow> <mtext>&nbsp;</mtext> <mi>dps</mi> </mrow> <mo>/</mo> <msqrt> <mrow> <mi>Hz</mi> </mrow> </msqrt> </mrow> </semantics> </math> </inline-formula>, and <inline-formula> <math display="inline"> <semantics> <mrow> <mtext>&nbsp;</mtext> <mn>1.42</mn> <mrow> <mtext>&nbsp;</mtext> <mi>dps</mi> </mrow> <mo>/</mo> <msqrt> <mrow> <mi>Hz</mi> </mrow> </msqrt> </mrow> </semantics> </math> </inline-formula>, for the roll, pitch and yaw rate with the in-run bias stability <inline-formula> <math display="inline"> <semantics> <mrow> <mn>1.62</mn> <mrow> <mtext>&nbsp;</mtext> <mi>deg</mi> </mrow> <mo>/</mo> <mi mathvariant="normal">s</mi> </mrow> </semantics> </math> </inline-formula>, <inline-formula> <math display="inline"> <semantics> <mrow> <mn>1.14</mn> <mrow> <mtext>&nbsp;</mtext> <mi>deg</mi> </mrow> <mo>/</mo> <mi mathvariant="normal">s</mi> </mrow> </semantics> </math> </inline-formula> and <inline-formula> <math display="inline"> <semantics> <mrow> <mn>0.84</mn> <mrow> <mtext>&nbsp;</mtext> <mi>deg</mi> </mrow> <mo>/</mo> <mi mathvariant="normal">s</mi> </mrow> </semantics> </math> </inline-formula> respectively.