A Capacitive 3-Axis MEMS Accelerometer for Medipost: A Portable System Dedicated to Monitoring Imbalance Disorders

Abstract

The constant development and miniaturization of MEMS sensors invariably provides new possibilities for their use in health-related and medical applications. The application of MEMS devices in posturographic systems allows faster diagnosis and significantly facilitates the work of medical staff. MEMS accelerometers constitute a vital part of such systems, particularly those intended for monitoring patients with imbalance disorders. The correct design of such sensors is crucial for gathering data about patient movement and ensuring the good overall performance of the entire system. This paper presents the design and measurements of a three-axis accelerometer dedicated for use in a device which tracks patient movement. Its main focus is the characterization of the sensor, comparing different designs and evaluating the impact of the packaging and readout circuit integration on sensor operation. Extensive testing and measurements confirm that the designed accelerometer works correctly and allows identifying the best design in terms of sensitivity/stability. Moreover, the response of the proposed sensor as a function of the applied acceleration demonstrates very good linearity only if the readout circuit is integrated in the same package as the MEMS sensor.

Thermal Performance of a Capacitive Comb-Drive MEMS Accelerometer: Measurements vs. Simulation

“…Each trimming may lead to slightly different results, as the trimming circuitry has limited precision of adjustment. Measurements taken as a function of a tilt angle and gravitational acceleration presented in [21] show a high degree of linearity of the MEMS and ROIC system operation. For a more precise shape comparison, the curves for acceleration equal to −1 and 1 g of this figure were shifted and overlapped with the curve for 0 g acceleration, and the resulting curves are presented in Figure 13.…”

“…Consequently, the displacement of the sensor caused by electrostatic force should be negligibly small with respect to the displacement caused by acceleration. In [21], we present a more in-depth analysis of the impact of electrostatic force on the measurement results.…”

MEMS capacitive accelerometer: A review

“…The magnitude of the acceleration is calculated by measuring the capacitance values. As a result of the acceleration, the values of the capacitances C1 and C2 are measured as in Equation 4 [36].…”

In-Home Older Adults’ Activity Pattern Monitoring Using Depth Sensors: A Review

“…Monitoring is the primary part of care; however, engaging a human to monitor the activity pattern of a senior 24 × 7 is a tedious task. Fortunately, it can be achieved using an intelligent system by analyzing the collected data of different sensors in real-time [ 9 , 10 , 11 , 12 , 13 ]. This system can be developed by integrating both wearable and non-wearable sensors.…”