There is an unusual phenomenon known to digital animators as the "uncanny valley" which occurs when a digitally animated human character’s portrayal is just close enough to be recognized as lifelike, but because of awkward movement or robot-like qualities, causes audiences to have a visceral negative response. Digitally generated human or animal characters for feature films and video games is therefore an exceptionally daunting challenge, as audiences must sense a fully representational character with fluid, 'true' motion in order to connect with the action.
Analog Devices, a leader in analog and digital signal processing and high performance MEMS motion sensing technologies, worked with Xsens to develop a high performance, high precision motion sensing solution for the Xsens' MVN camera-less motion capture suit that enables digital animators to mimic true motion. The form-fitting lightweight MVN suit is equipped with 17 distributed motion trackers, containing ADI Blackfin® processors for digital signal processing (DSP) and a total of 85 high performance ADI iMEMS® motion sensors. Camera-less inertial motion capture suits like the flexible Xsens MVN can be used indoors or outdoors, offering filmmakers an easy-to use, cost efficient system for full-body human motion capture.
Xsens' founders, initially inspired by the performance and market potential of early motion sensor technology for athlete performance measurement, are now industry leaders in the development of motion sensor-based products in diverse industries ranging from industrial to medical to entertainment. Continually driving the precision and breadth of motion sensor capabilities, Xsens has moved beyond sensor-only applications and expanded their development of multi-sensor data fusion capabilities, which combines inertial sensors with complementary technologies such as GPS and RF positioning. Xsens is a leading supplier of 3D motion tracking products using miniature MEMS inertial sensor technology, deploying thousands of motion sensors and motion capture solutions for use in 3D character animation, rehabilitation and sports science, and robot and camera stabilization.
Xsens selected Analog Devices' high performance, high precision MEMS inertial sensors and DSPs to ensure the delivery of motion tracking and motion capture products with best-in-class performance, quality and ease-of-use. These advanced ADI components enable Xsens to realize a seamlessly connected signal chain that ensures ultra precise, real-time coordination across multi-sensor systems.
Ensuring 6 Degrees of Freedom
To capture the nuances of an actor's movement, the Xsens MVN suit attaches inertial sensors to the body either with a LYCRA suit or straps worn underneath clothing, which gives the actor more natural freedom of movement for the most challenging action scenes. The highly accurate MEMS enabled motion trackers deliver smooth data that yields a full, realistic 6 degrees of freedom. Due to its lean weight, flexible design and wireless operation, the MVN is easily deployed regardless of environment, saving time and production costs. The Xsens MVN suit's capture of rich and fluid motion data requires no occlusion or marker swapping, enabling fast, real-time calibration of motion capture data. This real-time digital production process allows for iterative and integrated production editing, significantly reducing cost and post-processing time.
Xsens' state of the art technology has a direct impact on fulfilling a production's creative vision from pre-to post-production. MVN's real-time performance feedback enables the director to respond immediately to digital character input, enhancing the creative flexibility for the project. With simultaneous recording and viewing, directors assume active creative control of the digital character’s performance while in production, enabling them to push creative boundaries even further using integrated special effects.
MEMS Technology: Capturing Motion in Real-Time
Xsens' proprietary sensor fusion algorithms synthesize the MVN suit's motion sensor data with advanced biomechanical models to provide full-body motion capture output. This high fidelity output is made possible by data provided by seventeen separate motion trackers each containing two ADI iMEMS high precision accelerometers, three ADI iMEMS yaw rate gyroscopes and a Blackfin processor working together to provide an inertial measurement unit (IMU). Capturing motion with exceptional precision, the highly sensitive iMEMS motion sensors provide three axes of rotational acceleration (gyros) and 3 axes of linear acceleration (accelerometers), while Blackfin processors execute the math required to yield position and velocity calculations up to 1000 times per second and correlate the data from the distributed sensors. These seamlessly connected ADI components enabled Xsens to achieve a highly compact system form factor, with low power consumption and an optimal price/performance balance.
ADI and Xsens Technologies go to Hollywood
Game developers and special effects studios recognize the flexibility, quality and ease of use that the Xsens MVN brings to the creative production process, and benefit from the reliability and precision afforded by ADI's advanced technology. Xsens’ MVN was used recently by the previs studio of The Third Floor for previsualization work on the films Iron Man 2 and Alice in Wonderland. The MVN motion capture suit is also being used by Double Negative (known for Angels & Demons, Harry Potter and The Half Blood Prince, Quantum of Solace) during production of their in-progress film projects. Several other Hollywood visual effects studios have also adopted the MVN suit, including Industrial Light & Magic, and Sony Pictures Imageworks. The MVN suit has also been selected by game developers including Electronic Arts and Gearbox Software, which used the system for character animation in the Borderlands video game, and by Sony Computer Entertainment/Guerilla Games for Killzone 2.