
​How to visualize the movement
Applying the key concepts described above:
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Taking into account the possible presence of artefacts, and therefore having appropriately chosen the positioning of the IMUs
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Having positioned at least 2 IMUs for each joint to be described
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Having chosen the type of joint to be described and therefore an adequate biomechanical model
From the biomechanical model which has as input the data of all the IMUs it is possible to obtain the "joint kinematics" as output.
There are many mathematical forms that can be used to describe it. The choice derives from the final objective, i.e. what the final use of the data will be.
Sensor positioning
The correct positioning of the sensors is essential for the success of motion capture.
The mutual movement between the body and the sensors themselves can manifest as the main source of error in the final results.
Turingsense adopts validated measurement protocols that recall the previous history of studies in this area.


The Avatar
Let's assume we simply want to visualize the movement of a joint in 3D. The vast majority of 3D graphics systems allow you to visualize movement in the form of an avatar which already replicates, internally, a skeletal reference model. Within this model, assumptions are already made regarding the joints of the avatar. What remains is to provide the graphics system with movement data for each joint of the body. In this case, it is possible to simply provide the orientation data to the graphic system in the form of what is mathematically called a "quaternion". This method has the advantage of being very simple to manipulate, but has the disadvantage of not allowing the "guiding" of the avatar by faithfully following the biomechanical model previously used for the calculation.

The playback
​A classic of research in the field of motion capture is motion playback.
It may seem easier said than done, by revisiting the movement you just captured, it is possible to:
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Observe in slow motion (and in all directions(!) how the movement was performed by the person, in its simplest or most complicated steps
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Allow the subject to revisit their movements and realize any errors in their execution
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Being able to share your movement with professionals, friends, colleagues
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Being able to roughly compare several different sessions of the same movement
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Being able to cut out and investigate a certain portion of movement