Camera Robot Tracks Its Moving Pictures Via RFID

By Claire Swedberg

Move 'N See is using ultra-wideband technology from DecaWave as part of its indoor positioning and robotics solution, Pixio, enabling the automatic filming of moving athletes or other individuals.


French robotic video company Move ‘N See is adding RFID-based real-time location system (RTLS) technology to its automated video-tracking product for athletes. The Pixio robot, which operates a camera mounted on top of it, uses location data derived from RFID-enabled wristbands worn by the athletes. The result is an automated method of video-taping individuals as they move around a field, arena or other area, either indoors or outdoors.

The technology was intended to make it possible to record video of a moving person (such as a surfer or cyclist) without the need for someone to operate the camera. Eric Willemenot, a sports and video enthusiast with a background in satellite technology, saw a need for a solution that would make it easier to record video of athletes in action. Prior to launching the company, he recalls, he would often take videos in difficult places, such as using a helmet-mounted camera to record his fellow athletes as they skydived.

“Video tools are growing fast, and video use is growing fast,” Willemeno states. “But the problem is you need a cameraman behind the camera, and often there is no one available.” He founded his company in 2012 to develop robots that would take on the job of following an individual’s movements. The resulting videos could then be used for training purposes, as well as for promotion.

Move ‘N See launched a GPS-based product in 2013, Willemenot says. The initial product uses satellite locations to capture an individual’s position based on a relatively large device worn on his or her arm, which receives GPS signals and transmits the user’s GPS coordinates to the robot.

The GPS solution, known as E-Fullmotion, is still in use for outdoor applications, especially for scenarios in which an athlete may be a considerable distance from the camera and its robot. Customers have included surfers, wind surfers, kayakers, horseback riders, cyclists and skateboarders. In some cases, the customers have been the athletes themselves, while in others, a school or trainer purchased the system.

However, for indoor sports or other activities, the solution was not suitable for some situations. GPS doesn’t work indoors, and its location accuracy was insufficient for some applications. Therefore, approximately two years ago, Move ‘N See began working with DecaWave, an Irish firm that makes ultra-wideband (UWB) transceiver chips that can be used for RFID and RTLS applications, to develop the Pixio solution. The system consists of an RFID wristband with a rechargeable battery and DecaWave’s DW1000 UWB chip, which complies with the IEEE 802.15.4-2011 (UWB PHY) standard.

Three readers, which Move ‘N See calls beacons, and which also have built-in DecaWave DW1000 chips, are installed around an area in which an activity is being filmed, in order to receive transmissions from the wristbands. The robot employs Move N’See software to use the beacon to identify where the camera must be pointed. Location data is measured using the RF signal’s time of flight (TOF), which is then converted into a distance measurement.

“If you know the TOF distance between your wristband and each beacon, you can then apply trilateration algorithms,” Willemenot explains. The use of TOF, he adds, is the main differentiator between DecaWave technology and Bluetooth Low Energy (BLE)- or Wi-Fi-based systems that employ a received signal strength indicator (RSSI). “RSSI is not accurate, and [is] very sensitive to the environment. The use of TOF and UWB together is what makes DecaWave technology highly accurate and reliable.”

When an athlete—a horseback rider, for instance—wishes to begin recording, he uses buttons on his wristband to press “record.” He then begins moving around the area, and the transmissions from the wristband—consisting of the unique ID number encoded on the chip—are captured by the beacons. The TOF-based location data from the three beacons is forwarded to the Pixio robot, which uses Move N’See software to calculate the location based on trilateration of the individual, and then manipulates the camera accordingly.

Users provide their own cameras and mount them to the Pixio robots. Move N’See can recommend the best cameras for specific applications.

With the DecaWave UWB technology, Willemenot says, the Pixio system can determine an individual’s location based on his or her wristband, within about a distance of 30 centimeters (11.8 inches), which is the default setting. The technology could be more precise than that, according to Mickael Viot, DecaWave’s marketing manager, if a user chooses to configure the system to collect location data at a granularity down to several centimeters. However, Willemenot notes, that degree of granularity is not required for this application.

As an individual moves around the area, the camera follows him or her based on the location data, and stores the recorded video. It automatically corrects its zoom level based on the frame size that the individual has set using the Pixio robot’s buttons.

A single robot can be configured to track numerous people wearing wristbands, but the robot can monitor the movements of only one wristband at any given time—whichever band was set to record most recently. Each wristband position is updated 20 times per second.

The solution also comes with a free smartphone app that is now in development and will be released in an Android version. With the app, users could change zoom levels or designate which wristband the robot should track in the event that several bands are being used. The robot receives these instructions from the smartphone via a Bluetooth connection.

Move ‘N See is currently taking orders for the Pixio system, and plans to begin shipping in September 2015. The solution with three beacons, up to 16 wristbands and the Pixio robot costs €790 (about $890, including taxes).

Willemenot says he’s taking orders for the Pixio system from a wide variety of customers throughout Europe, North America, Australia and New Zealand. His company targeted about 30 outdoor sports for its GPS-based E-Fullmotion solution, he adds, while the Pixio UWB system could work with approximately 200 different indoor sports, including basketball, soccer, hockey and tennis.

In addition, Willemenot reports, end users have contacted the company for several non-sports applications. For instance, he says, some U.S.-based churches have been interested in utilizing the technology to automatically capture sermons or ceremonies on video. Colleges can use the system for recording lectures, while acting schools can provide the wristbands to its students as they move around a stage performing a part, thereby enabling them to view and improve upon their performances. The company also intends to offer the solution for dancers, so that they can view their routines as a training tool.

The Pixio wristband, which weighs 50 grams (1.8 ounces), can be placed in a pocket if a user doesn’t want to attach it to a wrist. Its range is about 100 meters (328 feet), and Willemenot says he has been pleased with the accuracy he’s seen while the system was being tested. “It’s a technological breakthrough for us,” he states, since it not only enables the use of robotics indoors, but also makes the tracking somewhat more precise than the GPS version. On the other hand, he notes, the GPS model is a better alternative for outdoor sports, in which participants may require a very long transmission range, such as 1 kilometer (0.6 mile).