Zebra Technologies product manager, John Fulton, discusses a rack tracking project with a major US vehicle manufacturer.
A major US OEM had a multi-million dollar problem with the purchasing and tracking of steel, reusable parts racks and wanted to be more efficient and save money. To address this they brought in Zebra Technologies to implement a tracking solution that utilises RFID tags. These tags send a signal every four minutes (as a standard setting), which is picked up by a receiving infrastructure at the OEM’s facility.
Based on which sensors receive the signal it is possible to triangulate the precise position of the rack within the facility.
“This provides an active, realtime locating system, with each rack having its own identity tag making it possible to track its movements and storage location within the plant,” explains product manager John Fulton.
The system is configurable so it can recognise a rack of a particular type (what type of load, fast or slow turn around) and its location in a specific production zone within the facility. It will also register how long that rack has been at that location (if it is a loading or unloading zone). This allows the system to automatically update the load status of the rack (i.e. full or empty) providing greater visibility to the usability of the rack fleet at any given time. “There are some features of the system that will allow us to capture the event even if it occurs in a short space of time such as under the standard four minute ‘blink rate’,” says Fulton.
The benefit to production is much better visibility of storage resources. Fulton offers a press shop as an example: “If the press shop is planning to begin a production run of a set number of panels they need to know if there are enough empty or undamaged racks, of the correct type on site, available to store the pressed parts. Otherwise costly delays can occur.”
Another issue relates to purchasing of large numbers of racks from the manufacturers. Often the new racks are delivered to the OEM’s facility in small batches and this can result in difficulty in accurately accounting for a complete order. “Clearly the OEM wants to know if the correct quantity and type of racks has been delivered,” says Fulton.
“The solution is to have the rack manufacturer apply RFID tags to the new units, so that when they arrive at the OEM’s facility they ‘blink’ to indicate the racks have arrived on site.”
This is a common cost issue with rack purchasing.
Once in use racks can become damaged and unusable.
This system also assists in the maintenance process, allowing the rack’s usability status to be flagged through the RFID tag. This can be done either at a remote PC workstation or by an operator responsible for the movement of the racks around the plant on a daily basis. “The flagging of a rack as damaged/unusable can also initiate communications to the maintenance department so action is taken to repair or replace the rack,” says Fulton.
It’s also quite common for functional changes to be made to the racks. The original configuration of the rack may not be suitable for later generations of parts for a given model or platform, so modifications are required. The system stores the rack’s revision level, ensuring that correct version of the rack is in use and provides information on the exact location, type and quantity of racking is available to production staff. Fulton explains: “If an operative is running short on a particular type of racking they are able to refer to a digital map locating additional (suitable) racks available in the facility and providing the quantity at that location”.
Updating the rack’s other statuses can be done automatically as it is placed in a predetermined zone (a designated maintenance zone for example), however, this can also be updated manually, as was the preference of the US OEM working with Zebra. This customer requested automation of the ‘full or empty’ status indication while all other statuses were to be updated manually, but they can still be automatically updated states Fulton: “Using a series of ‘WherePorts’ the rack’s tag is automatically triggered as it passes into a different zone or reaches a particular station in the production process. This can then signal a change in status. As such the system can become self-correcting. “We can create and modify the rules of operation according to the customer’s requirements.”
Fulton also points out that simpler (and cheaper) passive label type tags could also be used. The company is currently working on integrating this tracking system with its existing stock replenishment software known as Zebra’s Material Flow software. The application of the rack tracking system can go beyond the production department. Fulton suggests that purchasing are interested in using it to establish type, quantity and location of racks across a number of facilities, even to the extent of which model/platform they have been specified for.