Robotics ｜ Sample handling & automated measurement
Fully automated colour evaluation of optical filters with a robot
Robotic sample exchange × UV-Vis spectroscopy × real-time CIE chromaticity analysis. Everything from picking up the filter to measuring the transmission spectrum and plotting it on the CIE xy chromaticity diagram is fully automated. With every measurement, the chromaticity coordinates, L*a*b* and luminous transmittance appear on screen immediately, and the results are logged and accumulated automatically.
Demo video
The sequence runs from the robot picking up the sample, inserting it, measuring, through to returning it.
* The sRGB colour swatches on screen are for illustration; the quantitative results are the xy coordinates and the numbers.
The problem
Colour evaluation of materials and films centres on measuring the transmission spectrum with a spectrometer and converting it to colour coordinates. The measurement itself is quick, but mounting and removing the sample requires a person, so for inspections covering many samples, or repeated measurements under varying conditions, that becomes the bottleneck.
When a person swaps the samples, variation in how they are placed affects the measured value. If repeating a measurement on the same sample gives a different result, you cannot separate a real material difference from operator variability.
What we built
Sample exchange, spectroscopy, chromaticity analysis and logging are automated end to end.
01 Pick up
The robot arm picks a filter out of the rack.
02 Insert
It is inserted horizontally into the spectrometer stage.
03 Measure
The transmission spectrum is acquired with a UV-Vis spectrometer.
04 Analyse & log
CIE XYZ, xy chromaticity, L*a*b* and sRGB are computed from the transmittance, displayed immediately and logged automatically.
05 Return
The filter is returned to its rack and the robot moves to the next sample.
Seven filter types can be measured automatically in sequence, and the system can also be switched to measuring a single filter chosen by the operator.
Where it applies
Manufacturing & quality control
100% inspection of colour and transmittance for films, resins and glass; lot-to-lot colour difference (ΔE) control; blocking-rate inspection of UV-cut products. Periodic sampling inspections that used to need an operator present can run unattended, with every result logged automatically for traceability.
R&D
Multi-sample screening — concentration determination from solution absorbance, fixed-point measurement for ageing and weathering tests. Data accumulated by automated measurement connects to machine learning and Bayesian optimisation, extending into autonomous experiments: measure → learn → decide the next condition.
Swappable components
Sample (film → solution cell, powder, component) / instrument (UV-Vis → fluorescence, IR, film-thickness gauge, camera) / output (chromaticity → concentration, thickness, pass/fail). A configuration that keeps your instrument and automates only sample exchange and logging is also possible.
Summary
In this case we combined robotic sample exchange, UV-Vis spectroscopy and real-time CIE chromaticity analysis to automate the whole colour-evaluation workflow end to end. Taking the operator out of the rate-limiting mount-and-remove step, and removing the measurement scatter caused by how samples are placed, raises both throughput and reproducibility for multi-sample and repeated measurement.
* This system is an exhibition and proof-of-concept demonstration. Specific configurations, specifications and implementation details are discussed individually on enquiry.
Tell us about the experiment you want automated
We will ask about the target operation, the instruments you have and your sample throughput, then propose where to start.
- Unattended weighing, dispensing and sample exchange
- Control systems built around your existing instruments
- PoCs that connect automatically acquired data to analysis and experimental design