What is a product sorting system?
A product sorting system is an automated arrangement that identifies or classifies products according to defined characteristics, then directs each product to a selected path, destination or category.
It can combine a conveyor, sensors or machine vision, control logic and a mechanical gate, arm or diverter. The exact method depends on the product and the sorting criterion.
A brief overview:
- Sorting criteria can include colour, shape, size, material, weight or product type, with sensing selected for the specific application.
- A common arrangement combines a conveyor, sensors or a camera, control logic and a gate, arm or diverter to route products.
- Camera-based sorting performance can be affected by image clarity, camera resolution, conveyor speed, product movement and illumination conditions.
- Product handling around labelling can include conveying, spacing, orientation, accumulation, transfer, inspection, rejection and presentation around the wider line.
How does a product sorting system identify and route products?
Sorting starts with the characteristic that separates product groups. Sensing detects the relevant characteristic, control logic determines the route, and a physical mechanism carries out the diversion.
Sorting criteria and sensing methods
Colour, shape, size, material, weight or product type can provide the basis for classification.
The sensing approach is selected for the application. Camera-based identification systems can provide one source of data where the requirement involves visual or code-based identification, but a camera is not mandatory for every sorting system.
Detection, control and product diversion
A typical sorting sequence contains three connected stages.
Detection identifies or classifies the product. The controller determines the required response. A gate, arm, pusher or other diverter then performs the physical routing action.
The detection technology and diversion method can vary, but the same basic sequence applies: detect, decide and route.
What can affect product sorting performance?
Camera-based sorting depends on the quality and timing of the information available to the detection system. Image clarity, camera resolution, product movement, conveyor speed and illumination can all affect how reliably visual characteristics are detected.
Image clarity and camera resolution
Low-resolution or unclear images can make product features harder to distinguish.
Stable product presentation also helps keep the camera view consistent. Excessive movement or motion blur can reduce the usable visual detail available for classification.
The required camera and imaging arrangement therefore depends on the product characteristics that the system needs to distinguish.
Belt speed and illumination
As conveyor speed increases, the available image-capture time can decrease and motion blur can become more significant.
Lighting conditions also matter. Shadows, glare or insufficient contrast can make visual characteristics harder for a camera-based system to distinguish.
The appropriate speed, lighting and imaging arrangement depends on the product and application. Camera-based sorting performance depends on the specific system, product, operating conditions and production-line configuration, so speed, accuracy and throughput should be assessed for the intended application.
How does product sorting differ from rejection?
A product sorting system identifies or classifies products using defined characteristics and directs them towards a selected category or destination.
A reject system has a different purpose. It removes or diverts products that fail an inspection or another configured acceptance condition.
The physical equipment can overlap. A gate, arm or diverter may route products in a sorting system and may also remove non-conforming products in a reject application. The difference lies in the decision being carried out: sorting routes by classification, while rejection responds to a failed acceptance condition.
How does product sorting relate to product handling and end-of-line automation?
Product sorting can operate alongside the equipment that moves and presents products through a production line. Conveying, spacing, orientation and transfer can support how products reach the detection and routing points without defining the sorting decision itself.
Product-handling functions around labelling and inspection
A sorting requirement can be assessed alongside wider conveyor systems and product-handling functions. For example, conveying or presentation may control how a product reaches the detection point, while the sorting system still performs the classification and route decision.
A requirement to classify products by colour, size, material or type points towards sorting. Product-handling equipment can support that process without turning conveying or presentation into the sorting function itself.
Position within the end-of-line sequence
An end-of-line arrangement can include conveyors and spacing control, vision inspection, verification, reject or divert stations and final pack-off.
Product sorting should remain distinct from inspection, verification and rejection. A gate or diverter may form part of the sorting mechanism, but it carries out the route decision rather than making the classification itself.
Barcode reading captures information encoded in a barcode. Barcode verification assesses code quality against a defined verification method. Vision inspection checks configured visible features.
A sorting system makes the classification and route decision. A gate, arm or diverter carries out the physical routing. In a reject application, a similar mechanism may instead remove a non-conforming product.
Traceability connects items, batches, lots, pallets or shipments to records and events, so it should not be treated as a synonym for sorting. RFID is also a separate identification method based on radio technology rather than optical barcode reading.
These functions may sit around labelling systems within the same end-of-line arrangement, but each should be specified according to its own purpose.
The required equipment scope should therefore be defined around the specific production and routing requirement.
ALS Identify product handling systems around a product sorting system
Where a sorting requirement needs to connect with conveying, spacing, transfer or product presentation, ALS Identify can support the surrounding product handling systems. Define the products, sorting criteria, required destinations and relevant line constraints when discussing the wider arrangement.
