A novel piezoelectric dynamometer based on double-sensor for thermal compensation

Abstract

A piezoelectric dynamometer can produce thermal forces because of temperature fluctuations, thus affecting measurement precision. To investigate the influence of the thermal force on the dynamometer, this article proposes a hypothesis of decreasing the conduction power and establishes the function of a thermal force over time in an ordinary dynamometer based on the heat conduction differential equation. A novel double-sensor thermal compensation dynamometer is designed, with static calibration in constant temperature and force/heat coupling experiments, to solve the problem of the thermal force. The experimental results indicate that the nonlinearity and repeatability of the double-sensor thermal compensation dynamometer are less than 1% full scale (FS) of the static calibration at a constant temperature; in the force/heat coupling experiments, at a heating rate of 0.4 ℃/s to 110 ℃ with a loading force of 500 N, the maximal output deviation is less than 1.06% (FS), realizing the unidirectional thermal force compensation of the structure. The double-sensor thermal compensation dynamometer can be utilized in sharp temperature fluctuations environment, like rocket engine forces measurement.

Simulation of capacitive pressure sensor based on microelectromechanical systems technology

“…The difference between these pressures (32.46 Pa) is the sensor error under the mentioned conditions. The temperature sensitivity of the pressure sensor is 255 × 10 −6 K −1 .…”

“…Now, the same procedure is applied to calculate pressure error, which is 1160 Pa. Temperature sensitivity of the sensor in this case is 9112.75 × 10 −6 K −1 . It can be seen that with the spring K , temperature sensitivity of the structure is reduced significantly, which verifies our approach (Table 1).…”

“…5 Temperature compensation is one of the most important and active research areas in the field of MEMS sensors. Different methods have been reported in literature for the aim of compensating the effects of temperature variations on the sensors operations such as using of double sensors, 6 employing of micro oven 7 and electronically compensation methods. 8 This paper proposes a novel geometrical method for self-compensation of this error.…”

Sensor bonding surface parting parameter analysis and experiment

“…The development of the current machinery industry is becoming more and more precise, and the impact of microparameters on macro-mechanism has become a hot spot nowadays. Piezoelectric force sensors are a kind of self-generated power type sensors [1][2], which need to be pre-tensioned to eliminate the mounting gap. This results in a large number of bonding surfaces, and the morphological characteristics of the bonding surfaces have a significant impact on the performance index of the sensor.…”