7 results about "Accelerometer" patented technology

A mirror or other reflecting surface is used for collecting and reflecting incident solar radiation. The mirror is supported for independent motion about a pair of axes. An accelerometer generates signals representative of an amount and direction of motion of the mirror about each of the axes. Motors or other drive mechanisms independently drive the mirror about each of the axes. A tracking device provides information about the current position of the Sun. A control is connected to the accelerometer, the motors and the tracking device for maintaining a predetermined optimum orientation of the mirror as the Sun moves across the sky. Position sensors that sense the position of the mirror relative to the earth's magnetic field may also be employed.

A towrope type ocean controllable source electromagnetism and earthquake data collection system is composed of electric field sensors (non-polarized electrodes) distributed in three or more towropes uniformly or not, three-component induction coil type or three-component fluxgate type magnetic field sensors and sonic sensors composed of hydrophones or accelerometers and is used for measuring ocean three-component magnetic-field components, electric field components EX distributed in the cable direction, electric field components EY distributed in the vertical cable direction and ocean earthquake data. The towrope type ocean controllable source electromagnetism and earthquake data collection system can collect ocean electromagnetism data and ocean earthquake data in the time domain and the frequency domain at the same time, increase the collection quantity of ocean geophysics data of advancing construction at a time in a multiplying mode, effectively improve the target detection precision and explore and evaluate ocean mineral products, oil and gas resources and methane hydrates through combination and comprehensive application of ocean controllable source time-frequency electromagnetism and the earthquake exploration technology.

The invention discloses a method for correcting feedback of an inertial navigation system/global position system (INS/GPS) combined navigation system based on lever arm estimation. The method comprises the following steps of: extending a lever arm error to a system error state vector for estimation, judging whether a random error of an inertial device is accurately estimated through comparing whether the difference between a lever arm estimation value and a true value exists in an error threshold range, wherein the error of the inertial device is effectively estimated when the error of the lever arm estimation value is smaller than a set threshold value, measured outputs of a gyroscope and an accelerometer are corrected by utilizing the error of a random constant of the estimated inertial device, and unity feedback correction is performed during combined Kalman filtering, otherwise, feedback correction is not carried out on the error of the inertial device. According to the method, the error of the random constant of the inertial device can be subjected to effective estimation and unity feedback correction, and the precision of the INS/GPS combined navigation system can be effectively improved.

The present invention provides an angular accelerometer signal adaptive denoising method based on wavelet analysis. Compared with a conventional wavelet analysis denoising method, the method of the present invention comprises the steps of calculating the difference quotient of the wavelet energy entropies and the energy entropies of a signal with noise and a noisy signal to determine an optimal wavelet decomposition level of the signal with noise, applying the median filtering to evaluate a noise width and a noise standard deviation, and combining a 3 sigma criterion to set a threshold value to thereby carry out the adaptive filtering. At the aspect of the threshold value selection, the method has better effects by being compared with a conventional heuristic sure criterion, a maximum and minimum value criterion and a penalty criterion. The above methods have better effects on the denoising processing of a periodic signal and a high-dynamic signal of a molecule type liquid-ring angular accelerometer.

A high-g shock accelerometer is provided with an LCC case. A MEMs acceleration sensor is positioned in an interior of the LCC case. The MEMs acceleration sensor has exterior surfaces including top and bottom surfaces and side surfaces. An elastomer is in an adjacent relationship or in contact to a majority of the exterior surfaces and to the interior of the LCC case. The MEMs acceleration sensor with the elastomer attenuates LCC case strain sensitivity while retaining wide band frequency response.

The invention discloses a three-vector coarse alignment method. The method comprises the following steps: eliminating noise in measured values of a gyroscope and an acceleration meter by adopting Kalman filtering, wherein in the Kalman filtering, a residual x2 detection method is adopted to adjust a measurement noise covariance and a Kalman gain matrix in the current iteration, and the adjusted measurement noise covariance and Kalman gain matrix are used for the next iterative calculation; and inputting the noise-eliminated measured values of the gyroscope and the accelerometer into a preset three-vector alignment model, and performing coarse alignment. Meanwhile, the invention discloses a corresponding system. According to the method, noise in measured values of the gyroscope and the accelerometer is eliminated through Kalman filtering, the influence of the noise on three-vector coarse alignment is reduced, and the alignment precision is improved.

The invention provides a gyroscope detection range expansion method and system, and the method comprises the steps: calculating the angular acceleration of a carrier at the current moment according to the acceleration data of the carrier at the current moment collected by a plurality of acceleration sensors which are regularly arranged; based on a Kalman filtering algorithm, fusing the angular velocity, collected by a gyroscope, of the carrier at the current moment with the calculated angular acceleration, calculating real angular velocity information fused at the current moment, and estimating angular velocity information of the carrier at the next moment; wherein the plurality of acceleration sensors and the gyroscope are arranged on the circuit board, and the circuit board is arranged on the carrier. The accelerometer combination is installed according to a specific arrangement rule, the system receives data of the accelerometer combination and data of the angular velocity of the gyroscope at the same time, optimized angular velocity data can be obtained after data fusion, and the value of the angular velocity can still be accurately detected after the data exceed the measuring range of the gyroscope in the system.