RFID Brings Precision to Dice Rolls

By Claire Swedberg

EPC Solutions Taiwan has built a solution enabling 99.7 percent accuracy of automated dice-throw reads, with an RFID reader built into a throwing machine, six UHF RFID tags in each die and custom near-field antennas that can read tags with 1-centimeter precision.

Since its establishment in the 1990s, online gambling has become one of the most popular businesses on the Internet. It is legal in parts of North America, Europe and Asia, and was estimated as being a $56 billion industry in 2018. Several gaming machine companies are developing an online system that uses RFID to track the exact orientation of dice after they are thrown for Internet-based bets, thereby enabling online gamers to know, with certainty, what was thrown and thus whether or not they won.

The firms' online gaming solution, provided by EPC Solutions Taiwan, consist of a UHF RFID reader in an automated dice-throwing machine, as well as tags built into the dice. With the use of RFID, its automated system can identify each dice throw, based on which of six tags in each die is read and, therefore, the result of the throw. The data is then displayed online so that the casino or gaming company, as well as gamers, can view the results in real time. The product, known as Sicbo, has been in use for three years, and the company says that with RFID it has been providing more accurate gambling results than other automated systems.

There is an inherent risk for players of online games since, unlike with casino slot machines or table games, the online gambling process takes place remotely, so players cannot physically confirm the dice that are being thrown. Traditionally, companies have used human dealers and a webcam so that gamblers can see the dice as they are thrown. Gamblers place their bets online, with a dealer rolling the dice and then recording the results. Recently, casinos and gambling companies have moved to the use of machines. After players place their bets, adealer simply pushes a start button. The machine then rolls the dice and a camera mounted above the machine scans the points. The software calculates and displays the results for each gambler and identifies those who won.

These days, most online casinos are using such automated machines and camera-based systems. However, cameras alone cannot always provide the correct results. Light reflections on the dice sometimes alter the results, which can lead to a dispute between the system and players. For the gaming companies, that meant an accuracy rate of about 98 percent, which wasn't enough to assure players of almost certain accuracy.

The gaming companies, which have asked to remain unnamed, sought a way to provide automated throwing of dice without the potential failures of a camera system. It began working with EPC Solutions Taiwan in 2016 to develop a solution that would employ RFID to identify how the dice were thrown without failures, according to T.H. Liu, the company's president. The RFID firm then went about engineering a system that could detect an RFID tag at very close range, without capturing stray reads from other tags on the same die.

The resulting system consists of a UHF RFID reader built into the floor of the machine, along with six tags in each die. The reader only reads the tag on the side of the dice facing down, and the software can thus calculate the throw results. For instance, if a die lands with one dot facing the machine floor, the software will recognize that a six has been rolled. EPC Solutions Taiwan's engineers selected UHF RFID using an Alien Technology Higgs 3 RFID tag chip, as well as an Alien ALR-F800 reader, built underneath the machine's rolling surface. The company custom-designed the antennas for both the tag and the reader.

When it came to creating RFID-enabled dice, the challenge was in the size. The company had to accommodate six tags, one on each side, and the tags needed to be uniquely identified within very close proximity. "We worked with the dice manufacturer to embed RFID chips into the dice during manufacturing process," Liu explains. However, he notes, the system would also require the reader to read only one side of each die—the one facing down on the surface—and not the other RFID chips.

EPC Solutions Taiwan had tested HF 13.56 MHz technology, but it found that there were inaccuracies in the dice reads. "We found there were many null points—blind areas," Liu says. "So we redesigned using UHF." Together with the dice manufacturer, the engineers were able to position the UHF tags in the dice properly so that the nearest tag would always be read, without any stray reads from those on the other sides of the dice. The tags come with a custom-designed loop antenna sized at 0.5 millimeter (0.02 inch) square.

In the dice machine, the reader antenna, designed by EPC Solutions Taiwan, measures approximately 16 centimeters (0.6 inch) in diameter. The near-field antenna accomplishes a read distance of about 1 centimeter (0.04 inch). "It took us half a year to develop the antenna, and another half a year to develop the dice," Liu states. A further challenge was ensuring that the tags could withstand the hard knocks of dice being thrown many times. In fact, he reports, it was designed to endure one million rolls.

Since the system was released, EPC Solutions Taiwan has found that gaming machines are achieving 99.7 percent reading accuracy. The firm has provided gaming solutions for casinos, Liu says, but this is the first RFID system it has offered that reads dice to identify a throw. According to Liu, his company specializes in challenging use cases for RFID that require custom designs for tag and reader antennas.