Motion Capture is a widely used technology that records the motion of people or objects. This technology records the motion, and the information collected is then sent to computer software that provides photorealism in a virtual setting. It was developed for gait analysis in the life science sector, but it is now widely utilized by VFX studios, neuroscientists, sports therapists, and for the validation and management of robots and computer vision systems.
We use motion capture suits that place markers as close to the actors’ essential joints as possible. They have undergone numerous design iterations, were specifically created with this in mind, and are made of specialized materials. Using hook and loop Velcro, the optical markers are fastened to the suit. The markers will then be further attached using coloured neoprene patches. These patches help us identify the players on the screens and during post-production by preventing the markers from migrating to other parts of the body or to other performers.
How Motion Capture Works?
Motion Capture uses light reflections to capture movement. Markers are the performers who wear a suit covered in reflective dots. Cameras with customized lighting capture the movements of the marks as the actor travels around the studio. Calibration is required to ensure that the cameras are just capturing light from the markers and can see the actors’ movements. The 3D animated skeleton is created from these motions.
Some of the skeleton may vanish when the actor moves if the light on specific markers is obstructed. By telling the software what happened to those marks, a technician cleans the video. You are now prepared to record an action. The technician then goes over the tape one more time to ensure that all of the markers have the correct labels. Until all actions have been captured on film, this filming and cleaning procedure continues.
Techniques Used in Capturing Motion of an Object
Optical (Passive): This technique enables retroreflective markers to be affixed to people or things and reflect light coming from the direction of the camera lens. After being reflected, the light is utilized to determine and record the marker’s location in a three-dimensional space.
Optical (Active): This method allows markers to produce light instead of reflecting it. Thus, a power source is needed for the markers.
Marker-less: No markers of any kind are required for this procedure. It tracks and records moving people and objects using depth-sensitive cameras and specialized software. It is often regarded as less accurate than optical or mechanical-tracking alternatives.
Inertial: Inertial Measurement Units (IMUs) have sensors to monitor rotational rates used to record movement. Magnetometers, gyroscopes and accelerometers are the most prominent sensors found in IMUs.
Steps to Follow While Starting Motion Capture
Choose a Motion Capture Format
We advise you to only take into account optical passive for more significant projects with larger expenditures. A bodysuit, software and infrared-capable cameras are needed. The inertial kind is ideal for all other uses. You can capture interior mocap in any setting with any set pieces as long as you have Wi-Fi.
Choose a System and Software
The majority of motion capture systems include proprietary software that was created to work well with their cameras or suit.
Ensure the Integration of Mocap Data
Several studios only use Autodesk products, such as Blender, Unity, Maya, Unreal Engine, Houdini and Cinema 4D. Ensure your systems can incorporate the mocap data that was taken.
Detect Motion and Clean the Data
Although motion capture data is susceptible to errors, it can also be extremely accurate. When moving quickly and erratically, the margin of error grows. Hence, if your movements are intricate, be mindful of the additional animation time you could require in post-production.
Overall, motion capture is becoming prominent in the animation of characters. It has become an essential tool in modern animation production, allowing for more fluid and lifelike movements in character animation.