UR3e

What it's for

The UR3e is the smallest cobot in the Universal Robots line, with a 3 kg payload and a 540 mm reach, so it fits on an ordinary table and needs neither a hall nor a fenced cage. Six degrees of freedom are enough for pick&place, light assembly and feeding parts to machines, and the force/torque sensor at the tip lets it "feel" the pressure while inserting components.

The manufacturer lists three main roles: electronics assembly, pick&place and quality inspection. In quality control the UR3e holds a part in front of a camera or touches a measuring probe to successive points, repeatably and without eye fatigue. In the laboratory it serves as an arm that moves test tubes and plates between instruments, because a short reach means a small risk zone around the person. In small-batch production it has one advantage over a dedicated automat: changeover is a new program and a different gripper rather than a rebuild of the machine. Add tools such as grippers (Robotiq, OnRobot) and force sensors (ATI Industrial Automation), chosen for the specific operation.

Where does the UR3e have no business? Anywhere a part weighs more than about a kilogram together with the gripper, because the 3 kg payload includes the tooling. For palletizing, tending large machine tools or welding you need a bigger sibling, for example the UR5e or UR7e. If, on the other hand, you are building an assembly cell in a factory with many small stations, several UR3e units side by side may work out better than one large robot. The same goes for the laboratory and schools, where safety in close work with people and the ability to program without a weeks-long course matter.

Who it's for

Yes: for companies with small-batch production of electronics and small components that want to replace monotonous benchtop assembly. Yes: for research and testing laboratories where the robot moves samples or runs measurements. Yes: for technical universities that want equipment also used in industry, and therefore teaching real skills (see “Educational Robots for Schools and Universities”).

No: for plants that need a payload above a few kilograms or a long reach; then look at the higher models in the series. No: for those seeking the lowest price on the market; the UR3e is not a hobbyist robot, and its cost is the cost of industrial equipment. No: for companies with no plan for integration, since the robot alone is only the start and the gripper, software and safeguards have to be planned. If you do not know where to begin, read “How to Buy a Cobot Step by Step” and “What Is a Cobot and How Does It Differ from an Industrial Robot”.

Deployments

All we know is that the robot is offered in Poland by elmark.com.pl. What exists in the category: “Cobots” is the most developed segment of collaborative robotics, with many models available from Polish distributors. If you want to see the UR3e at work, ask the distributor about a demo station or for references from your industry.

UR5e: the same manufacturer and the same ecosystem, but a 5 kg payload and an 850 mm reach. Choose it when the parts or the gripper are heavier than the UR3e can lift.

FANUC CRX-3iA: a FANUC cobot with the same 3 kg payload; it tempts with a brand known from factory floors, and the family is described in “FANUC CRX: The Cobot Series with 8 Years of Zero Maintenance”.

KUKA LBR iisy 3 R760: 3 kg payload and a listed price of about 23.4 thousand EUR (roughly 102 thousand PLN); sensible if KUKA dominates in the plant.

igus ReBeL: a 2 kg payload and about 22.7 thousand PLN. Much cheaper, but it is equipment for learning and light tasks, not an equivalent of the industrial class.

DENSO COBOTTA: a 0.5 kg payload and 4 kg weight; for the finest operations, not for work with a 3 kg gripper.

The UR3e reached the market in 2018 as the smallest member of the Universal Robots e-Series. The company from Odense, Denmark, founded in 2005, is regarded as one of the pioneers of the collaborative robot market, and the e-Series equipped the arms with a built-in force/torque sensor. The UR3e joined the larger models that we describe in the comparison “Universal Robots UR5e, UR10e and UR20 Compared”. There are no separate events on record from the history of this specific model, so we do not add later generations or dates that cannot be confirmed. Today there are a dozen or so models of this brand, from the UR3e to the heavy UR20 and UR30.