Projectile Muzzle Velocity Measurement via Waveguide Electromagnetic Calibration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for determining the muzzle velocity of a projectile are not precise and are influenced by temperature changes and the shape of the projectile tip, which affects the accuracy of measurements.
Innovation Solution
A measuring device using a smooth waveguide with a transmitter and receiver coupler, where the electromagnetic field is detected before and after the projectile's passage, allowing for calibration and compensation of temperature-related influences, and the use of a signal generator to excite specific waveguide modes for accurate velocity measurement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If electromagnetic waves are used to measure muzzle velocity, then measurement capability is provided, but temperature changes and projectile tip shape influence measurement accuracy
Solution Approach 1:
The system performs preliminary calibration measurements by moving a mirror through the waveguide to establish reference data before actual projectile measurements. This preliminary action creates a baseline that accounts for waveguide characteristics, enabling subsequent compensation of temperature and geometric variations during actual measurements
Solution Approach 2:
The system uses feedback by comparing actual projectile measurements against the calibration reference data. The evaluation device processes the difference between measured electromagnetic field changes and calibration data to compensate for temperature changes and projectile tip shape variations, improving measurement accuracy
2Adaptability or versatility
If the waveguide is operated above the limit frequency, then waveguide modes can be utilized, but the measurement becomes sensitive to temperature and geometric variations
Solution Approach 1:
The system changes the operating parameter by operating the waveguide below the limit frequency for the relevant waveguide mode. This parameter change reduces sensitivity to temperature and geometric variations while maintaining measurement capability through alternative measurement approaches
3Speed
If direct measurement of current muzzle velocity is performed, then real-time velocity data is obtained, but the measurement is influenced by projectile tip shape variations
Solution Approach 1:
The system extracts and separates the projectile tip shape influence from the measurement by using calibration data that accounts for geometric variations. The evaluation device isolates the velocity information from the tip shape effects through comparison with reference measurements
Solution Approach 2:
The system introduces an intermediary calibration process that mediates between the raw electromagnetic field measurements and the final velocity determination. This intermediary step compensates for projectile tip shape variations before the final velocity calculation
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method provides a precise and accurate determination of muzzle velocity, independent of temperature changes and projectile shape, by normalizing the change in electromagnetic field during projectile passage, ensuring reliable speed measurement.
Implementation Method 1
a signal generator (e.g. oscillator) delivers a signal with a constant center frequency... The oscillator 4 stimulates a waveguide mode via the transmission coupler 2
Implementation Method 2
The electromagnetic mode is measured in a first step Field without a projectile 6... the change in the electromagnetic field over time is recorded
Implementation Method 3
A smooth tube of any desired cross-section is preferably used as the waveguide... a first smooth tube 1 of any desired cross-section is used as a waveguide
Data Source
Figure 1~2
AI summary
The invention relates to a device for measuring the muzzle velocity (V0) of a projectile (6) or similar and to a method that can implement said device. Said device comprises: a weapon barrel or a filling barrel as a wave guide (1), a signal generator (4) that is electrically connected by a signal supply to at least one emission coupler (2) for exciting the weapon or filling barrel (1), and a receiving line for transferring the measured signals of at least one receiving coupler (3) to an evaluation device (5). The distance between the emission coupler (2) and the receiving coupler (3) is variable and can be individually selected according to the selection mode of the wave guide (1). The position of the receiving coupler (3) in relation to the emission coupler (2) depends upon the preferred measuring method. The receiving coupler (3) is disposed between the base of the projectile and the emission coupler (2) if the speed is measured after the projectile (6) has passed, and the receiving coupler (3) is between the tip of the projectile and the emission coupler (2) if the speed is measured (V0) prior to the passing of the projectile (6). When both measuring methods are combined, at least two receiving couplers (3) are integrated and the emission coupler (2) is then placed between both receiving couplers (3). The electromagnetic field of the empty weapon and filling barrel (1) is measured without the projectile (6), in front of the projectile (6) or behind the projectile (6) or in combinations therewith. The muzzle speed (V0) is determined from the measured signals.