Electrical computers: arithmetic processing and calculating – Electrical digital calculating computer – Particular function performed
Reexamination Certificate
1998-05-26
2001-05-29
Ngo, Chuong Dinh (Department: 2121)
Electrical computers: arithmetic processing and calculating
Electrical digital calculating computer
Particular function performed
C702S142000
Reexamination Certificate
active
06240435
ABSTRACT:
BACKGROUND OF THE INVENTION
Sensors convert nonelectrical physical or chemical quantities into electrical signals. The behavior of semiconductor sensor devices is modeled, under a series of assumptions, by a system of nonlinear partial differential equations and associated boundary and input value conditions. For such sensors, it is essential to solve numerically at least some of the equations in order to obtain a meaningful result describing environmental conditions encountered by the sensor. Mechanical sensors also suffer from some of the same issues relating to nonlinearity and associated boundary and initial value considerations.
When the desired result is determined by the integration of sensor output over time, errors of bias scale, and nonlinearity occur. Mathematical algorithms are used to improve the accuracy of the result by correcting for such errors of bias, scale and nonlinearity.
The present invention relates to methods and devices of determination of an input signal which changes in time as well as of its integral value.
Methods are known of the above mentioned general type and disclosed for example in Inventor's Certificates of the USSR 1,453,418 and 1,541,635. In accordance with the method and device disclosed in these references, integration is performed to a given value of the integration result. This objective is presented for example in inertia systems of targeting, for turning off an engine when a rocket reaches a desired speed V
r
. The input signal in this case is an acceleration which is measured by accelerometer, and its inaccuracies are a main source of error of the system as a whole. The device includes a convertor
1
for a frequency of pulse sequence, a frequency multiplier
2
, an integrator or pulse counter
3
, a source of reference signals
4
, keys
5
and a control device
7
. A code corresponding to a desired value of speed is introduced into the pulse counter by integration of reference signals (accelerations) during a time corresponding time interval. The values of the reference signals can be obtained by turning a sensitivity axis of the accelerometer relative to a local vertical. Then, during measurements of the input signal which is the acceleration during a flight, an inverse integration is performed. In other words, the pulses from the convertor, multiplied many times by the frequency multiplier are deducted in the counter from the code obtained during the time of direct integration when the counter was operating for addition of the reference signals. A system of equations was used to determine the reference signals and time intervals. The nature of change of the input signal was approximately known beforehand, and therefore an initial moment of the input signal was calculated. Zeroing of the pulse counter is a signal that the speed reached the desired value. The above described method has a high accuracy. However, it has some disadvantages, namely the fact that the high accuracy is guaranteed in only one point and not along the whole scale of speed changes. This values must be known in order to determine of the location of a rocket. The known method and device are not always technically implementable since it is necessary that one reference signal is greater and the other is smaller than an average value of the input signal. However, the acceleration can reach a few g while on the ground during giving of the reference signals not always there is a standard of acceleration more than 1 g.
SUMMARY OF THE INVENTION
Accordingly, it is an object of present invention to provide a method and device which eliminates the disadvantages of the prior art.
In keeping with these objects and with others which will become apparent hereinafter, one feature of present invention resides, briefly stated, in a method of determination of an input signal changing in time, in which conversions which were performed for a final point in accordance with a known algorithm disclosed in the prior art, is also performed for final point t
n
for intermediate t
1
, t
2
, t
k
in accordance with a modified algorithm, so that it is possible to use not reference signals which are required by change curve of a changing acceleration, but reference signals which are available or in other words can be less than 1 g. The desired movement parameters are determined during the flight, and therefore a deviation of the acceleration curve from an expected acceleration curve does not reduce the accuracy.
In accordance with another feature of the present invention the device is provided with means for performing the above mentioned conversions for intermediate points as well.
The novel features which are considered as characteristic for the present invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
REFERENCES:
patent: 4030038 (1977-06-01), Daniel et al.
patent: 5031134 (1991-07-01), Kaplan et al.
patent: 5490067 (1996-02-01), Teguri et al.
patent: 5790442 (1998-08-01), Ninomiya et al.
Ngo Chuong Dinh
Zborovsky I.
LandOfFree
Method and device of determination of an input signal which... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and device of determination of an input signal which..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and device of determination of an input signal which... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2477255