Thursday May 26, 2022

XY tables: How do they differ from Cartesian and gantry systems?

Currently, there exist different means of building up the Cartesian coordinates of X, Y, and Z.

What we use in describing these systems are based on the way the axes are being linked, the position that the load is in, and what the system is used for.

Gantry and Cartesian robots are quite common in a lot of industrial applications, while in those precision applications, people prefer to make use of XY tables. Why is this so? This is because these tables are quite small, rigid, as possesses high accuracy levels in positioning and travel.

Cartesian systems

This system possesses either two or three axes of XYZ, XZ, and XY. They normally come with an end effector, as well as a rotational component. They are able to orient the workpiece while offering linear motion in more than one of the Cartesian coordinates.

Usually, when the Cartesian system is made use of, the load will be cantilevered, originating from the outermost to the innermost axis. The outermost axis is either the Z or Y.

In the case of an X-Y gantry, their load is hinged on the Y-axis. Sometimes, it may be hinged on either the axis’ end or far from the Y-axis.

This system makes the load capacity restricted, especially when its outermost axis comes with quite a lengthy stroke. While this goes on, it creates a big moment on those supporting axes that are lower.

The Cartesian systems are designed to be used in a myriad of situations and come with the maximum number of strokes on every axis that is at most one meter.

This system is designed to work in the following applications are assembly, dispensing, and pick-and-place.

Gantry systems

Gantry systems are designed to make use of two axes, and sometimes, two Z and two Y axes to solve the problem of the outer axes leading to a moment load on the inner axes.

Gantry systems, in a lot of cases, use three axes, such as X, Y, and Z.

In the gantry system, the load is sited inside the footprint of the gantry, while the gantry is hinged on the working area.

If the parts are unable to be handled by the above, the gantry systems can easily be calibrated to work from under.

This system works well in those applications that need long strokes, strokes that are more than a meter long. The gantry system can also transport large payloads that can’t be done well with a cantilevered design.

A common use of this system is the overhead transport like transporting big automotive parts from a station to a different one while an assembly process is ongoing.

XY tables

The XY tables bear similarities to the XY Cartesian systems because they both have two axes of X and Y that are hinged on each other. They are also similar because they possess strokes that are at most a meter in length.

The major disparity between the XY tables and XY Cartesian systems is the way the load is placed. In the Cartesian system, it is cantilevered, while in XY tables, the load that rests on the XY table is close to the Y-axis, having no generous moment.

XY tables are designed to work solely on their footprint. What this means is that under no condition does the load move past the Y-axis.

This is why XY tables are great for those scenarios where you have to position a load on the horizontal plane (X-Y). A great way of showing this is placing the semiconductor wafer for inspection. Another way is positioning a part for machining processes.

Those XY tables that have open frame are said to come with an opening at the center of those tables.

The open aperture of this table permits them to be used in those cases, where items have to be passed through. It is great for applications like back-lit inspection, as well as the insertion processes.

You can easily identify an XY table because they come with an opening in the middle of that table. Out of all of them, the XY table is the most flexible.