Shaft angular acceleration is one of the most important parameter of rotary machines, the error of angular acceleration increased when the shaft speed up. For this problem, a new high accuracy angular acceleration measurement system is presented, the principle of measurement is self-regulating the period of speed sampling signal according to the proportion of the shaft speed up. This measuremen...

The stability of a railway bridge is mainly governed by level of acceleration, vertical displacement, and twist. While acquiring acceleration is relatively easy task in the data measurement respective, displacement and twist are very challenging due to lack of appropriate sensors. Furthermore, as most existing displacement sensors are confined to measuring single displacement, twist which is ob...

High precision measurement of acceleration levels is required to allow active control for vibration isolation platforms. It is necessary to propose an accelerometer configuration measurement model that yields such a high measuring precision. In this paper, an accelerometer configuration to improve measurement accuracy is proposed. The corresponding calculation formulas of the angular accelerati...

The wearable sensor system developed by our group, which measured lower limb angles using Kalman-filtering-based method, was suggested to be useful in evaluation of gait function for rehabilitation support. However, it was expected to reduce variations of measurement errors. In this paper, a variable-Kalman-gain method based on angle error that was calculated from acceleration signals was propo...

We report experimental results on the acceleration component probability distribution function at R λ = 690 to probabilities of less than 10 −7. This is an improvement of more than an order of magnitude over past measurements and allows us to conclude that the fourth moment converges and the flatness is approximately 55. We compare our probability distribution to those predicted by several mode...

[1] Measurements of streamer velocity reflect the detailed internal microphysics of sprite development that is connected to the effects streamers create in the mesosphere. We report intensified high speed video observations of streamer development acquired at 5,000 to 10,000 frames per second that include the entire altitude range of sprites ( 40–90 km). Downward streamers accelerate to a maxim...