Identification of sample cells in a chromatography autosampler

A method for identification of sample cells of a sample tray placed in a chromatography autosampler, each sample cell having (i) a container having a translucent or transparent side wall, and (ii) a cap having an end surface visible from the sample tray, the method comprising:

• top scanning, with a camera assembly of a machine vision (MV) module of the autosampler, the end surfaces of all the sample cells;
• gripping, lifting, and rotating, with a cell gripper of the autosampler, each of the sample cells such that each of the sample cells is gripped while in the sample tray, lifted from the sample tray, and rotated above adjacent sample cells of the sample tray;
• side scanning, with the MV module, the side walls of each of the sample cells, with the camera assembly;
• returning, with the cell gripper, each of the sample cells to the sample tray;
• determining, with a computing device, an identity of each of the sample cells within the sample tray based upon the top scanning;
• determining a bottom liquid level at a lowermost portion of an inner volume of each sample cell;
• identifying an inner bottom surface of the sample cell and a foreign object within the sample cell, and
• controlling the sampling needle assembly and limiting the insertion depth of a sample needle of the sampling needle assembly based on a position of the bottom liquid level, the bottom surface, and the foreign object of a respective sample cell to avoid damaging the sample needle,
• wherein the computing device controls the MV module.