How a robot picks parts off a conveyor

A pick and place cell pairs a camera, a conveyor and a robot arm. The camera spots each item and the controller tracks it as the belt moves, so the arm can meet it on the fly, grab it with a suction cup or gripper, and drop it in a bin. Whether one robot is enough comes down to simple arithmetic: picks it can make per minute versus items arriving per minute.

Controls

Labels

Animation speed

Robot cycle time per pick

Conveyor speed

Spacing between items

Step through it

Seeing the itemsA camera over the belt finds each item's position and orientation. An encoder on the conveyor tells the controller how far the belt has moved since.
Picking on the flyThe robot does not stop the belt. It predicts where the item will be, matches its speed, and grabs it with a suction cup.
Place and returnOne cycle is reach, pick, carry, place and return. Most of that time is robot motion, so shorter moves and lighter grippers raise picks per minute.
OverloadedSpeed the belt to 30 m/min with items 200 mm apart and 150 arrive each minute. A one second robot only manages 60, so 90 slip past.
Faster robotA high speed robot with a 0.4 second cycle reaches 150 picks per minute, just enough for that line.

The throughput math

A robot that needs c seconds per pick can make 60 / c picks per minute at best. Items arrive at the belt speed divided by their spacing: a belt at 12 m/min with items every 250 mm delivers 48 per minute.

If arrivals exceed capacity, the extras pass the robot. Lines then add a second robot downstream, slow the belt, or spread items farther apart.

Try it: start at a 1 second cycle and 12 m/min. The robot keeps up with 12 picks per minute spare. Raise the belt to 20 m/min and it falls behind by about 20 items per minute, then fix it by cutting the cycle time to 0.7 seconds.

What real cells add

Real capacity is lower than 60 / c because of gripper vacuum time, items that land too close together, and pick zones the arm cannot reach in time. Engineers validate true picks per minute with prototype tests. This model is a simplified teaching estimate, and the scene runs at half speed.

Where Avid uses this

Avid works on agricultural robotics, where the same vision plus motion timing decides how fast a machine can handle produce.

Sources

Perception and Motion Planning for Pick-and-Place of Dynamic ObjectsCarnegie Mellon University, Robotics Institute
Selection and Optimization of the Parameters of the Robotized Packaging Process of One Type of ProductSensors (MDPI, open access)

How to cite this model

Avid Solutions International. (2026, November 11). How a robot picks parts off a conveyor [Interactive 3D model]. Avid Field Lab. https://avidsolutionsintl.com/explore/robotic-pick-and-place

Last updated November 11, 2026

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