Robotic sorting arm that classifies and distributes objects

The problem

Manual sorting in packaging plants and recycling centers is slow and tiring, and errors rise as the hours go on. Ready-made industrial sorting systems cost tens of thousands, so small workshops can't afford them and keep sorting by hand.

How it works

1. TransportThe conveyor belt moves objects at a known speed.
2. ImagingThe camera captures the object and extracts its color and shape.
3. InspectionThe metal proximity sensor identifies the material.
4. DecisionThe system merges the readings and decides the object's class and its bin.
5. CaptureThe arm calculates the object's position at the moment it arrives and picks it up.
6. MeasurementThe system logs the correct-sorting rate and throughput.

Project features

• Three sorting criteria in the same device: color, shape, and material.
• Metal detection with a separate sensor, since the camera can't tell metal from plastic of the same color.
• Synchronizing the conveyor with the arm: the object is moving, so picking must calculate its position at the moment of arrival.
• A clear performance metric: the correct-sorting rate and pieces per minute.
• Classification can be extended with a new class through brief training, without rebuilding the system.

Expected challenges

These are the main obstacles to expect during the build, laid out clearly so you know them before you start.

• Lighting is the first factor in color classification: any change in light can flip the result.
• Synchronizing the arm with the conveyor is harder than the classification itself: an error of a few hundredths of a second drops the piece.
• Overlapping or touching objects confuse both the camera and the arm.
• Servos heat up and lose precision with continuous operation.
• The gripper must fit the object's shape; one gripper can't pick up every object.

The consultation gives you a solution for each one.