Tool Detection Device Using Pulsed Light Pattern Recognition
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing tool detection systems face challenges with misalignment due to vibrations, limited reflectivity of tools, interference from coolant and debris, and false triggers from coolant or swarf, especially in laser-based systems, which affect the accuracy and safety of tool detection in machining processes.
Innovation Solution
A detection device using a light transmitter with varying intensity and circuitry that records and compares signal patterns during repetitive motion to identify the presence of a tool, allowing for safer operation and reduced false triggers by analyzing light reflections and ambient noise separately.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a laser transmitter is used to detect tools through reflected light, then the detection range and capability are improved, but the average output power may exceed safety limits
Solution Approach 1:
The laser transmitter operates in pulsed mode rather than continuous wave, transmitting light in periodic bursts. This allows the peak power during pulses to be high enough for reliable detection while the average power remains below safety thresholds. The detection system synchronizes with these pulses to capture reflected light during active transmission periods.
Solution Approach 2:
The system dynamically adjusts the transmission characteristics by using variable intensity pulses. The light transmitter can modulate its output intensity based on detection requirements, environmental conditions, and safety constraints, optimizing the balance between detection capability and safety compliance.
2Reliability
If the light transmitter operates continuously, then the detection coverage is improved, but the periodic power output must be reduced to maintain safe average levels
Solution Approach 1:
The system uses periodic pulsed transmission where the transmitter activates in regular intervals. During each pulse period, full power is available for reliable detection, while the duty cycle ensures the average power remains safe. The receiver is synchronized to detect during these periodic active periods.
3Device complexity
If a simple threshold-based detection system is used, then the device complexity is reduced, but false triggers from coolant or swarf increase
Solution Approach 1:
The system incorporates feedback mechanisms where the detection signal is analyzed in the context of the tool's rotational position and motion patterns. The controller compares detected light reflections with expected patterns based on tool geometry and rotation phase, enabling discrimination between genuine tool reflections and false targets like coolant droplets or swarf.
Solution Approach 2:
The system uses preliminary characterization of the tool's geometric features and rotational signature to establish expected detection patterns before actual machining begins. These pre-established patterns serve as reference templates for validating subsequent detections, allowing the system to reject anomalies that don't match the known tool characteristics.
4Ease of operation
If the transmitter and receiver are aligned directly, then the setup simplicity is improved, but vibrations cause misalignment affecting detection accuracy
Solution Approach 1:
The transmitter and receiver are combined into a single integrated detection unit or housing, maintaining their relative alignment fixed with respect to each other. This mechanical coupling ensures that vibrations affecting the tool or workpiece do not cause differential misalignment between transmitter and receiver, as they move together as one unit.
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
The solution enables accurate detection of rotating tools by pattern recognition, reducing false triggers and ensuring safe operation within acceptable laser safety limits, while also accounting for tools with multiple cutting edges and geometrical changes, thus improving machining efficiency and reducing scrap.
Implementation Method 1
a light transmitter and a light receiver positioned relative to the light transmitter to receive light reflected by the object
Data Source
AI summary
A device and method for detecting the presence or absence of an object which has repetitive motion are disclosed comprising, a receiver for receiving a signal from the object, and circuitry for determining the presence or absence of the object to be detected, wherein the circuitry records the signal from the receiver as a pattern of data during at least part of the repetitive motion of the object, compares the data with a previously recorded data pattern and, produces an output signal based on the comparison. The signal may be received during discrete time intervals, and may be light which can be transmitted with varying intensity. The circuitry may determine the value of signal received at a receiver and produce a binary value. The signal received at the receiver can be reflected from the object to be detected.