Sensor Array Position Determination with Opposing Read-Out Directions
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing position determination methods for code-carrying carriers, particularly at high read-out speeds, suffer from errors due to nonlinearities and nonidealities in sensor elements and signal output stages, leading to distorted peak detection and inaccurate position values.
Innovation Solution
The solution involves using sensor arrays with opposing read-out directions to compensate for displacement errors, allowing for error correction and improved accuracy by averaging position values from pairs of sensors read in the same and opposite directions, and employing CMOS arrays for non-destructive reading.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If high read-out speeds are used for fast position determination, then productivity is improved, but measurement precision deteriorates due to nonlinearities and nonidealities in sensor elements and signal output stages
Solution Approach 1:
The patent creates a complementary copy of the sensor array with inverted read-out direction. This copy detects the same optical signal but processes it in the opposite direction, allowing the system to obtain two measurements (one with error, one without) from the same physical measurement event, thereby enabling error correction without requiring additional measurement time
Solution Approach 2:
The patent inverts the read-out direction of at least one sensor array relative to the movement direction. By reading out pixels in the opposite direction to the carrier movement, the system creates a measurement that is insensitive to certain types of errors (such as those caused by nonidealities in the signal output stage), allowing these errors to be identified and corrected by comparing with the normally-oriented sensor array
2Measurement precision
If complex correction methods are used to improve measurement precision, then measurement precision is improved, but device complexity increases
Solution Approach 1:
The patent merges the error correction function into the normal position determination process by using sensor arrays that are already part of the basic system configuration. The complementary sensor array uses the same optical path and detection mechanism as the primary array, simply inverted in read-out direction, thereby correcting errors without adding separate correction hardware or complex processing systems
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 approach significantly reduces errors associated with read-out frequency, light intensity, and temperature-dependent drifts, enabling precise and fast position determination even at high speeds without the need for complex or costly components.
Implementation Method 1
a sensor array extending at least over part of a code or of a graduation has to detect the imaging of a code excerpt onto the sensor array
Data Source
AI summary
To determine the positions of a code on a movable support, said support can be moved in a displacement direction relative to a sensor element comprising at least one sensor array in the vicinity of said array. The sensor array or arrays determine(s) the position of imaged code elements that can be differentiated from radiation in the vicinity of the sensor elements, the recorded values being read out in at least one read-out direction and positional values being determined from said values. The array or arrays is or are read out twice from opposite read-out directions, or one sensor pair consisting of two sensor arrays, is read out as a pair from opposite directions. Positional values are derived from the positions of the differentiated code elements and said values are averaged to provide a position with an improved accuracy. The accuracy can thus be increased by simple means.