What is the principle of mechanical capture and motion capture technology of motion capture instrume

Mechanical motion capture devices install angle sensors in rotatable joints to measure the angle of rotation of the joints. When the device is moving, the position and motion trajectory of the end point of the member in space can be obtained according to the angle change measured by the angle sensor and the length of the connecting rod. The advantage is that it is not affected by environmental light, electromagnetic interference and other factors, with high precision and good real-time.

The disadvantage is that complex mechanisms need to be worn, which limits the freedom and comfort of the exerciser, and also increases the cost and maintenance of the system.

Motion capture technologyIt is a technique that records and processes the movements of people or other objects in three-dimensional space. Motion capture technology can make the movements of digital models more realistic and fluid, and it can also capture subtle movements of the face or fingers, which is known as performance capture.

The history of motion capture technology can be traced back to the early 20th century, when some scientists and artists began using cameras to record the movement of people or animals. With the development of computer graphics and sensor technology, motion capture technology has gradually become an important means of creating realistic characters and scenes in films, games, virtual reality, and other fields. The principle of motion capture technologyIt is mainly the use of external equipment to record data and restore the displacement of human structures or other objects, these devices can be divided into optical, inertial, mechanical and other different types, each of which has its own advantages, disadvantages and scope of application.

Motion capture technology has a wide range of applications, and in addition to the entertainment field, it can also be used in medical, educational, military, sports, and other aspects, such as analyzing human posture, diagnosing diseases, simulating training, improving sports performance, etc. The trend of motion capture technology is to move towards higher precision, lower cost, easier operation and more diversity, such as using artificial intelligence methods such as deep learning to optimize data processing and generation effects, or leveraging mobile devices such as smartphones to achieve macro portable and low-cost motion capture.

The optical motion capture system uses a camera or other optical equipment to record the position and movement of the marker points or feature points attached to the capture object, and then reconstructs the three-dimensional posture through the Qin computer vision algorithm. Optical motion capture systems usually use infrared light and reflective marking points, which can be divided into two types: calibration and non-calibration: the calibration system needs to be pasted with reflective or luminous balls on the first capture object, and the non-calibrated system can directly identify the natural characteristics of the human body or object.

Motion capture technology is commonly used at this stageOpticalwithInertial typeTwo, we independently developed optical motion capture system, and have a better understanding of this field.

Optical motion captureAs the name suggests, it is through the optical principle to complete the capture and positioning of objects in the field. It is to capture the position information of the marker fixed on the human body or object with an optical lens to complete the motion and posture capture. Optical motion capture relies on a complete set of sophisticated and complex optical cameras, which use the principle of computer vision, by multiple high-speed cameras to track the target feature points from different angles to complete the capture of the whole body action.

Optical motion capture can be divided into two types: passive and active. This classification is distinguished by the marker. Active means that the marker is actively emitting light and can even have its own ID encoded, so that the lens can observe it through the marker's own light in the field of view, and record the trajectory of the captured movement.

The passive optical motion capture is to emit a specific wavelength of infrared light through the light board of the lens itself, which is irradiated to the marker, and the marker can reflect the infrared light emitted by the lens light board through special reflection treatment, so that the lens can capture and record the movement trajectory of the marker in the field of view.

In optical motion capture, because the active marker needs to be powered by the accessories and wiring required to fix the marker, the optical motion capture that is now used in the mainstream is almost the samePassive optical motion capture。In the fields of automated control, motion analysis, gait analysis, virtual reality, ergonomics, film and television animation, passive optical motion capture is often more advantageous.