User Manual

 Insert each MTw, into the correct strap holder. Note the location of the MTw ID with

respect to the body location, for future use.

 For consistency, it is recommended to display the Xsens text in the correct orientation

for reading – this means that the cup should be the lowest point.

 Attach the straps to the appropriate body segments.

 Check that the straps are fastened tightly enough to the body.

 To do this, the subject wearing the straps should walk or run for a few seconds, or

perform sample movements that will be made during the measurements. If the

straps become loose, re-tighten them and repeat the check.

NOTE: When tightening the straps, pull the strap at the point where it runs through the

plastic buckle, not just at the end!

4.4.3 Recommended Locations

While inertial sensor technology facilitates freedom of movement and minimises restrictions

imposed by camera and lighting, users should remain as vigilant when placing inertial

sensors to the body as when placing any other human measurement system to the body.

Users should be aware of skin motion artefact, which can occur with all forms of human

(movement) measurement systems. When placing Xsens MTw to the body, using the Click-in

body straps helps to ensure that the MTw is fastened tightly and robustly to the skin. The

following points should be taken into consideration:

 Be aware of muscle contractions that may cause unwanted movement of the MTw

 Place MTw’s on areas with least likelihood of moving due to a muscle contraction.

 For measurements of the extremities, for example forearm, take into account the

measurement desired. At Xsens, we place the MT closer to the wrist, as this provides

more information about 3D movement. Furthermore, the wrist area has less fatty tissue,

decreasing the chances of skin motion artefact. (See 4.4.4 for instructions for fastening

the forearm strap.)

 For the upper arm, the location is less critical, as the upper arm has more musculature.

 On the lower leg, two locations have been described in literature as good placement.

1. On the tibia, close to the knee

2. On the lateral side of the lower leg, aligned with the fibula, 6cm above the lateral

malleolus

 For upper leg measurements, we recommend placing the MTw close to the knee, on the

lateral thigh, as this has less probability of having fatty tissue, compared e.g. to closer to

Configuration sheets with recommended MTw positions for full body measurement are

available upon request.

Cloete, T.; Scheffer, C.”Repeatability of an off-the-shelf, full body inertial motion capture

system during clinical gait analysis” Engineering in Medicine and Biology Society (EMBC),

2010 Annual International Conference of the IEEE 11 Nov 2010 pp 5125 - 5128

Cutti AG, Ferrari A, Garofalo P, et al. ‘Outwalk’: a protocol for clinical gait analysis based on

inertial & magnetic sensors. MED BIO ENG COMPUT, 2010; 48(1):17-25.