A wearable motion tracking system for capturing a relative position between a first body part (101;104) of a user and a second body part (102,103,106-108) of said user , said wearable motion tracking system comprising: at least one first measurement device (120a;120b) attachable to said first body part (101;104); at least one second measurement device (121a;121b) attachable to said second body part (102;103;106-108); and a computing device adapted to communicate with at least one of the first and second measurement devices such as to retrieve measurement data of measurements between the first and second measurement devices; wherein said at least one first measurement device (120a;120b), said at least one second measurement device (121a;121b) and said computing device are configured such as to obtain by said computing device a plurality of measurements between said first measurement device (120a;120b) and said second measurement device (121a;121b), wherein said plurality of measurements between said first measurement device (120a;120b) and said second measurement device (121a;121b) comprises at least one distance measurement between said first measurement device (120a;120b) and said second measurement device (121a;121b); and wherein said computing device is configured to compute, in three dimensions, a position of said second measurement device (121a;121b) relative to said first measurement device (120a; 120b) using said plurality of measurements for tracking the position of said second body part (102;103;106-108) relative to said first body part (101;104), characterized in that said plurality of measurements between said first measurement device (120a;120b) and said second measurement device (121a;121b) comprises at least one direction measurement between said first measurement device (120a;120b) and said second measurement device (121a;121b). at least one first measurement device (120a;120b) attachable to said first body part (101;104); at least one second measurement device (121a;121b) attachable to said second body part (102;103;106-108); and a computing device adapted to communicate with at least one of the first and second measurement devices such as to retrieve measurement data of measurements between the first and second measurement devices; wherein said at least one first measurement device (120a;120b), said at least one second measurement device (121a;121b) and said computing device are configured such as to obtain by said computing device a plurality of measurements between said first measurement device (120a;120b) and said second measurement device (121a;121b), wherein said plurality of measurements between said first measurement device (120a;120b) and said second measurement device (121a;121b) comprises at least one distance measurement between said first measurement device (120a;120b) and said second measurement device (121a;121b); and wherein said computing device is configured to compute, in three dimensions, a position of said second measurement device (121a;121b) relative to said first measurement device (120a; 120b) using said plurality of measurements for tracking the position of said second body part (102;103;106-108) relative to said first body part (101;104), characterized in that said plurality of measurements between said first measurement device (120a;120b) and said second measurement device (121a;121b) comprises at least one direction measurement between said first measurement device (120a;120b) and said second measurement device (121a;121b). <EOS>