Buying a Used Robot With Vision: What the Demonstration Must Identify

A used robot may be sold with a camera and a demonstration program that locates a part. The demonstration is useful evidence, but it does not establish that the vision system will work with a different workpiece, lighting arrangement or camera position. Before purchase, identify the complete vision setup and agree what must be tested after it is installed at the buyer's site.

List the hardware and software in the offer

Record the camera, lens, mounting hardware, lighting, controller, cables and any external computing equipment. Ask for model numbers, serial identifiers and the software versions used during the demonstration. Identify which items are included in the sale and which belong to the seller's test cell. A robot arm offered without the demonstrated camera or light is not the same configuration.

Ask whether the vision software, calibration files and any optional licenses can be transferred and used by the buyer. Keep the seller's answer with the equipment list. If a license or component is missing, include the cost and availability of a replacement in the purchase review rather than assuming it will be included later.

Record the camera's physical position

A camera can be mounted on the robot or fixed relative to the cell. Record its mounting location, orientation and relationship to the work area during the demonstration. Photograph the setup and retain any drawings or configuration records provided by the seller. If the camera or mount is removed for shipment, the buyer should plan for the installation and calibration work required at the new location.

Universal Robots' camera mounting guidance for its AI kit notes the need for consistent camera positioning and says calibration should be repeated after the camera position is adjusted. This is guidance for a specific product; the applicable procedure for another vision system must be checked with its manufacturer or integrator.

Look beyond a clear image

A sharp image is helpful, but the vision task also depends on what the camera can see and how the image relates to the robot's work area. Record the workpiece, viewing position, camera distance and the region used in the demonstration. Ask what features the system uses to identify the part and whether it was tested with the range of positions and orientations expected by the buyer.

Universal Robots' camera calibration instructions explain that calibration must be repeated after changes affecting the camera's position on the robot. A calibration result is tied to its setup and procedure. A seller's file does not automatically prove that the camera is calibrated after transport, remounting or changes to the workcell.

Document lighting and workpiece conditions

Ask which lights were used, how they were positioned and whether surrounding light affected the demonstration. A buyer's factory may have different reflections, shadows or ambient conditions. Record the workpiece material, surface finish and any variation represented in the test. A demonstration using one clean sample does not establish performance across a production batch.

Keep a record of any protective enclosure or shade used during the demonstration. If that equipment is not included in the sale, the buyer needs to understand how it will reproduce the intended imaging conditions. Ask the integrator which changes require a new evaluation and what evidence will be used to judge the result at the new site.

If the application involves recognition software trained on images, ask what data was used, what rights accompany it and whether it represents the buyer's parts and environment. Do not assume that an existing model or training set can be transferred with the robot. The supplier or integrator should explain what validation is needed at the destination.

Agree on an acceptance test

Before purchase, define the intended task and the representative parts, positions and environmental conditions for a test. Record the number of attempts, successful results, failures and any operator intervention. Keep the raw observations and the test conditions with the report. A small demonstration can reveal useful issues, but it cannot establish long-term reliability by itself.

Installation and testing must follow the site's safety procedures and the equipment manufacturer's instructions. A vision result is not automatically a safety function. The complete robot application, including the tool, workpiece and surrounding equipment, needs the appropriate assessment by qualified personnel.

Close the handover with open questions

Keep the equipment list, camera mounting information, calibration records, software terms, demonstration results and unresolved compatibility questions together. Agree who will remount the camera, perform any required calibration and verify the system at the buyer's site. If the seller cannot provide a file or license, write that limitation into the purchase record.

For another used-equipment issue, read our support lifecycle guide and browse the used robot archive. A documented vision setup helps the buyer distinguish what was demonstrated from what remains to be validated.