Surveying Instrument Aiming via Iterative EDM Distance Refinement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In surveying instruments with cameras, determining correct horizontal and vertical rotation angles for an EDM beam is challenging when the camera center and instrument center are non-coaxial, as rotation angles calculated from the camera image do not directly apply to the instrument's optical axis, requiring a known distance to derive accurate angles.
Innovation Solution
A method involving coarse and fine distance measurements to calculate and adjust rotation angles, starting with initial assumptions and refining based on pixel differences in the camera image, allowing the EDM beam to be accurately aimed at a target selected within the camera's field of view.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If rotation angles are determined directly from camera image without iterative refinement, then the aiming process is simple and fast, but the accuracy of aiming the EDM beam to the selected target is insufficient due to camera-instrument eccentricity
Solution Approach 1:
The patent applies preliminary action by first performing a coarse distance measurement to obtain an initial distance estimate, which is then used to calculate preliminary rotation angles. This preliminary aiming positions the instrument close to the target before the fine adjustment step, effectively breaking down the complex aiming task into manageable stages that improve overall precision without requiring the entire system to be perfectly calibrated at once.
Solution Approach 2:
The patent implements feedback through its iterative refinement process. After calculating rotation angles based on the camera image and current distance estimate, the instrument performs a distance measurement to the aimed point, uses this measured distance to recalculate more accurate rotation angles, and repeats the process. This feedback loop continuously improves aiming precision by using actual measurement results to correct and refine the rotation angle calculations.
2Measurement precision
If the instrument uses a single distance measurement approach, then the measurement process is simple, but it cannot provide both coarse positioning and fine accuracy adjustment
Solution Approach 1:
The patent applies segmentation by dividing the distance measurement process into distinct coarse and fine measurement stages. The coarse measurement provides initial positioning and is used for calculating preliminary rotation angles, while the fine measurement refines the distance value after the instrument has been aimed more accurately. This segmentation allows each measurement to serve a specific purpose in the overall aiming and measurement process, improving efficiency by avoiding unnecessary high-precision measurements at early stages.
Solution Approach 2:
The patent implements dynamics by making the measurement process adaptive and iterative. The instrument dynamically adjusts its aiming based on feedback from distance measurements, and the measurement precision is dynamically optimized by performing coarse measurements when the instrument is far from the target and fine measurements when closely positioned. This dynamic approach optimizes the balance between measurement time and accuracy throughout the aiming 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 precise aiming and measurement of targets by iteratively refining rotation angles using coarse and fine distance measurements, ensuring the EDM beam aligns correctly with the selected point, even when camera and instrument centers are eccentric.
Implementation Method 1
a distance along said intermediate line of sight is measured
Data Source
AI summary
A method for aiming a surveying instrument towards a selected target is disclosed. The method includes, in at least one embodiment, capturing an image using a camera in the surveying instrument; selecting a target by identifying an object point in the image captured by the surveying instrument; calculating first horizontal and vertical rotation angles based on the object point identified in the image; rotating the surveying instrument over the first horizontal and vertical rotation angles to an intermediate line of sight; measuring a distance to a point along the intermediate line of sight; and calculating second horizontal and vertical rotation angles based on the object point in the image and on the measured distance. In at least one embodiment, the method may be implemented using computer software, hardware, firmware or a combination thereof. There is also disclosed a surveying instrument in which at least one embodiment of the method is implemented.