Radar Measurement of Extruded Tubes Using Total Reflection Peaks
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing radar measurement methods for tubular objects after extrusion face challenges due to unknown refractive indices, deformation of inner surfaces, and misalignments, leading to inaccurate determination of geometric properties like outer diameter, inner diameter, and wall thickness.
Innovation Solution
A radar measuring method and device that adjusts the radar transceiver vertically to detect total reflection peaks without partial reflections, allowing for the determination of refractive index and geometric properties by analyzing beam geometry and travel time, enabling precise measurements even with deformations and without requiring complex positioning systems.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the radar transceiver measures through the center of the pipe, then the measurement can directly determine geometric properties, but partial reflection peaks cannot be determined precisely due to surface deformations and misalignments
Solution Approach 1:
The invention extracts and utilizes only the total reflection peak from the measurement signal, deliberately ignoring the unreliable partial reflection peaks. By focusing exclusively on the total reflection peak which remains detectable despite surface deformations, the method achieves reliable geometric property determination without being compromised by the instability of partial reflections.
Solution Approach 2:
The invention changes the measurement approach from relying on partial reflection peak positions to using the propagation delay of the total reflection peak combined with the vertical position of the transceiver. This parameter transformation allows accurate geometric property calculation through the relationship between propagation delay, transceiver position, and pipe dimensions, bypassing the need for stable partial reflection peaks.
2Ease of operation
If a special mirror arrangement and focusing of THz radiation is used, then measurement can be performed, but errors occur if the pipe is positioned off-center
Solution Approach 1:
The invention makes the measurement system dynamic by moving the radar transceiver vertically along the pipe. Instead of requiring precise static positioning of both the transceiver and pipe, the method continuously adjusts the transceiver position and uses this positional information combined with propagation delay to calculate geometric properties. This dynamic approach eliminates the need for complex mirror arrangements and focusing optics while maintaining measurement accuracy even with off-center pipe positioning.
Solution Approach 2:
The invention replaces the complex mechanical mirror arrangement and focusing optics with a simpler system using a moving transceiver and computational evaluation. The mechanical complexity of aligning mirrors and focusing THz radiation is substituted by electronically controlling transceiver movement and using software to process the measurement signals, achieving the same measurement capability with reduced hardware complexity and improved robustness to positioning errors.
3Measurement precision
If the radar beam is transmitted through the pipe material, then geometric properties can be measured, but significant attenuation and absorption of the radar beams occur
Solution Approach 1:
The invention performs a preliminary empty measurement without the pipe in place to establish a reference propagation time. This preliminary action allows the system to later calculate the propagation delay through the pipe material by comparing the measured total reflection peak timing against the reference, enabling geometric property determination without requiring the radar beam to maintain high energy levels throughout the measurement process.
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
Enables reliable measurement of tubular objects by determining refractive index and geometric properties without partial reflection peaks, overcoming issues of surface deformations and misalignments, and providing accurate outer and inner radius measurements.
Implementation Method 1
a radar transceiver (6) emits a radar transmission beam (Th) along an optical axis (A6), receives reflected radar radiation and generates a signal amplitude as a function of time or frequency
Implementation Method 2
the speed of light of radar radiation in the tube is determined by the refractive index
Data Source
Figure 1~2
Figure 3
Figure 4a~5
AI summary
The invention relates to a method for measuring a tubular measuring object (4), in particular after its extrusion, with the following steps: guiding the tubular measuring object (4) in an object adjustment direction (z) through a measuring space (3) between a radar transceiver (6) and a reflector (8), - emitting a radar transmission beam (Th) from the radar transceiver (6) along its optical axis (A-SO) in a transverse direction (x) through the measuring space (3) to a reflector (8) and back to the radar transceiver (6), while determining an idle propagation time (tp0), - adjusting the radar transceiver (6) in an adjustment direction (y), which is preferably perpendicular to the transverse direction (x), and emitting and receiving the radar transmission beam (Th) in different adjustment positions (SO, S1, SM, SU), - upon detection of a measurement signal which has: = a total reflection peak (P1) with a Runtime shift (Delta t) compared to the empty measurement,and = no further partial reflection peaks, measuring the adjustment position (ys) and the transit time shift (Delta t), - measuring an outer radius (r) of the tubular measurement object (4), and - determining the refractive index (n) of the tubular measurement object (4) from the recorded values. The invention also relates to a corresponding device.