What is the Difference Between Cartesian and Gantry Robots?
Cartesian and gantry robots are both types of linear robotic systems. Instead of being stationary with rotational movement like the more traditional articulated robot, these robots move in a straight line along a rail system. The rail system of both robot types features multiple axes that run perpendicular to one another creating a rectangular or cubic work envelope. The terms cartesian and gantry are often interchanged with one another, however, these robot types are not exactly the same. While both move linearly, the main differences between them are how their axes are configured, how the workload is positioned, and the distance they are capable of covering.
Cartesian RobotsCartesian robots consist of either a two axis or a three axis configuration. Two axis cartesian robots may be configured as either an X, Y setup or an X, Z setup. Three axis cartesian robots will have all three X, Y, and Z axes.
Workload positioning for cartesian robots is always supported on one of the outer axes, either the Y or Z axis. With a two axis cartesian X, Y robot the workload will be supported by the Y axis while a three axis cartesian the workload can be supported by either the Y or Z axis. Since cartesian robots use only their outer axes for supporting workloads their payload capacity can be limited.
Cartesian robots are commonly used for automating pick and place, assembly, and dispensing applications. Cartesian industrial robots are mainly used to automate processes requiring a travel distance of one meter or less.
The advantages of cartesian robots include their ease of programming and well defined work envelope. Since cartesian robots only move linearly, programming is simplified as there are fewer motions to calculate and only two to three axes to consider, unlike with the FANUC Lr Mate 200ic and other traditional robots. The rectangular work envelope of cartesian robots is well defined by their grid system making it easy to visualize, which can help with safeguarding and part placement.
Gantry RobotsWhile the number of axes for cartesian robots can vary between two and three, gantry robot grid systems always consist of all three X, Y, and Z axes. Another difference between gantry and cartesian configurations is gantry robots use two X axes. Some robots feature two X axes classifying it as a gantry robot as opposed to a cartesian robot. Some gantry robot systems may also have two Y or two Z axes.
Workload placement for a gantry robot is centralized within its footprint as opposed to only being supported by an outer axis as is the case with cartesian robots. The centralized workload placement allows gantry robots to overcome one of the limitations of cartesian robots which is payload capacity.
Gantry robots are used to automate applications requiring a travel distance greater than one meter. Gantry robots are commonly used for part transfer, palletizing, picking, machine loading, and assembly applications.
The advantages of gantry robots are their higher payload capacity and longer reach capabilities. The extra X axis provides additional support allowing gantry robots to handle heavier workloads for their size. Centralized workload positioning also helps increase their payload capacities. Their workload positioning also allows them to overcome the reach limitations of cartesian robots to cover greater distances.