Low-frequency vibration is a harmful factor that affects the accuracy of micro/nano-measuring machines. Low-frequency vibration cannot be completely eliminated by passive control methods, such as the use of air-floating platforms. Therefore, low-frequency vibrations must be measured before being actively suppressed. In this study, the design of a low-cost high-sensitivity optical accelerometer is proposed. This optical accelerometer mainly comprises three components: a seismic mass, a leaf spring, and a sensing component based on a four-quadrant photodetector (QPD). When a vibration is detected, the seismic mass moves up and down due to the effect of inertia, and the leaf spring exhibits a corresponding elastic deformation, which is amplified by using an optical lever and measured by the QPD. Then, the acceleration can be calculated. The resonant frequencies and elastic coefficients of various seismic structures are simulated to attain the optimal detection of low-frequency, low-amplitude vibration. The accelerometer is calibrated using a homemade vibration calibration system, and the calibration experimental results demonstrate that the sensitivity of the optical accelerometer is 1.74 V (m·s−2)−1, the measurement range of the accelerometer is 0.003–7.29 m·s−2, and the operating frequencies range of 0.4–12 Hz. The standard deviation from ten measurements is under 7.9 × 10−4 m·s−2. The efficacy of the optical accelerometer in measuring low-frequency, low-amplitude dynamic responses is verified.

Low-frequency vibration is one of the harmful factors that affect the accuracy of micro-/nano-measuring machines because its amplitude is significantly small and it is very difficult to avoid. In this paper, a low-cost and high-precision vibration generator was developed to calibrate an optical accelerometer, which is self-designed to detect low-frequency vibration. A piezoelectric actuator is used as vibration exciter, a leaf spring made of beryllium copper is used as an elastic component, and a high-resolution, low-thermal-drift eddy current sensor is applied to investigate the vibrator’s performance. Experimental results demonstrate that the vibration generator can achieve steady output displacement with frequency range from 0.6 Hz to 50 Hz, an analytical displacement resolution of 3.1 nm and an acceleration range from 3.72 mm s−2 to 1935.41 mm s−2 with a relative standard deviation less than 1.79%. The effectiveness of the high-precision and low-cost vibration generator was verified by calibrating our optical accelerometer.

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The dynamic characteristics of a probing system directly affect the accuracy of dynamic measuring results and should be investigated comprehensively. Many methods can be used to identify the dynamic model of a probe. However, the uncertainty evaluation for the identified probe model remains a problem. A method based on signal transmission chain analysis is proposed in this paper to evaluate the uncertainties for dynamic identification of a micro contact probe. Taking a homemade micro contact probe as an example, the adaptive recursive least squares method is adopted to identify the probe model parameters according to the step input signals and the corresponding output signals of the probe. The signal transmission chain analysis method is utilized to analyse the source of uncertainties and their transmission relationships. The Monte Carlo method is employed to evaluate and combine the uncertainties of the obtained model parameters. Evaluation results are verified by experiments. The results of uncertainty evaluation can guide the compensation and improvement of the dynamic characteristics of the probing system. The proposed method can also be used to evaluate the uncertainties of dynamic identification for other sensors.