Conveyor Tracking

The Business Issue

The Civil Aviation Authority (CAA) enforce UK legal requirements for the carriage of dangerous goods by air. In order to address these requirements a leading logistics provider needed to identify and track packages containing particular dangerous goods that might be routed by air - for example lithium batteries, nail varnish, aerosols, perfumes and other liquids. This ideally needed to be done at the time the goods were passing through the x-ray security screening process without the need to open any bags or packages. The tracking system needed to be completely non-intrusive such that no additional manpower would be required and there would be no reduction in throughput at its air freight sorting and screening centres. Furthermore, local IT infrastructure was not available to transfer collected data back to a central system.

In order to fit in with the process custom hardware and software would need to be developed to meet the requirement.Codegate was initially approached to develop suitable hardware, tracking software and a cloud based solution to collect and record the tracking data.

The Solution

Proof of concept

Codegate initially designed and built a trial RFID reading system that could be installed in front of an x-ray machine, together with a display fitted next to the main x-ray image screens. At the start of the shipping process packages containing dangerous goods would be marked with a UHF Gen 2 RFID tag. Each tag was uniquely identified in accordance with a GS1 numbering format. As containers of mixed freight were fed into the x-ray machine the front end RFID reader would pick up the number of individual RFID IDs found on packages within the container. As the container moved into the x-ray chamber that number was displayed next to the x-ray screens enabling the screener to quickly verify it against the number of visible dangerous goods packages. If there was a discrepancy the container could be set aside to remove any dangerous goods packages that were not correctly labelled.

The RFID reader was housed in a protective enclosure with a single board computer, GPRS router and other electronics. Data could therefore be sent to the cloud via a mobile phone network. It also allowed Codegate to access the computer remotely in order to carry out diagnostics and software updates.

The trial ran for three months, during which time ergonomic feedback was received from the users and other interested parties to ensure that the level of additional distraction to screeners was reduced to to an acceptable minimum. Despite extremely high levels of interference from the x-ray machines themselves the required gap between adjacent freight containers (necessary to ensure RFID tag reads were assigned to the correct container) was gradually reduced to a level which eliminated any drop in overall throughput performance.


The proof of concept units showed the technology was capable of delivering the level of accuracy and reliability required to track dangerous goods through the process, even when the number, size and orientation of packages within each container could be considered random. There was also no control over package contents, including the presence of materials that would affect the read performance of the RFID system. This was further compounded by the very close proximity of adjacent x-ray machines, machinery and infrastructure metalwork. Phase 2 was therefore to design and build prototype production units for deployment to one screening site, and to further fine-tune the system to minimise such contaminating effects.

Codegate was selected to design, produce and install the prototype units at one trial site. Six months of intensive on-site testing followed in order to steadily improve the hardware configuration and software algorithms to the point where performance was acceptable even at over 100 times the expected level of dangerous goods throughput. At the same time the equipment was put through rigorous compliance testing resulting in CE approval and certification.

Work then began on the cloud system to receive data from all installed scanning machines and make it available simple summary formats over the web. This would allow data from individual machines and sites to be looked at in isolation, as well as keeping a transaction history of every single package.

Delivery and maintenance

Following a successful pilot Codegate procured full production units and rolled the system out nationwide. A cloud based maintenance and incident reporting system was developed to support the system, enabling users to report problems on line 24/7, with a next working day fix SLA. Since all installed systems can be accessed by Codegate remotely many issues can be resolved without an on-site visit being necessary.

Because the system was designed to be flexible it can be adapted for installation into many general conveyor systems. All software was developed in-house by Codegate, and therefore can be adjusted to meet particular process requirements. The number, type and configuration of RFID antennas can be changed to optimise performance with different environments and asset types. As each unit only requires a power socket connection it can be installed in areas where WiFi or LAN connectivity is unavailable or intermittent.

In Conclusion

This application example illustrates Codegate's capability to develop custom hardware and software, and to tackle ground-breaking proof of concept developments. Backed up with system integration, cloud services, ongoing helpdesk and maintenance support for both hardware and software Codegate can deliver any level of system development up to and including the complete solution.