Warning: Undefined array key "DOKU_PREFS" in /is/htdocs/wp1019470_OPI92FFHXV/www/_lauflabor_v3/inc/common.php on line 2082

Warning: Cannot modify header information - headers already sent by (output started at /is/htdocs/wp1019470_OPI92FFHXV/www/_lauflabor_v3/inc/common.php:2082) in /is/htdocs/wp1019470_OPI92FFHXV/www/_lauflabor_v3/inc/common.php on line 2090

Warning: Cannot modify header information - headers already sent by (output started at /is/htdocs/wp1019470_OPI92FFHXV/www/_lauflabor_v3/inc/common.php:2082) in /is/htdocs/wp1019470_OPI92FFHXV/www/_lauflabor_v3/inc/actions.php on line 38
Locomotion Laboratory
Stylesheet style.css not found, please contact the developer of "django_v3" template.

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Both sides previous revision Previous revision
Next revision 		Previous revision
Next revision Both sides next revision
start [2019/07/24 10:51]
Martin Grimmer 		start [2019/08/14 14:21]
Christian [News]
Line 24: Line 24:
 ====== News ====== ====== News ======
  
-  * **Movement Academy on Parkinson Gait** The Lauflabor organizes the [[http://wiki.ifs-tud.de/biomechanik/aktuelle_themen/bewak2019|first movement academy]] in Darmstadt on June 4 and 5, 2019 +  * {{::ansymb_logo_i.png?90 | Teaching course ANSYMB II}} **Running upcoming winter term!** [[http://www.ansymb.tu-darmstadt.de/|   Analysis and Synthesis of Human Movements]]
- +
-  * **Dynamic Walking 2019** is announced! Click [[http://dynamicwalking.org/index.php/dw/2019|here]] for details. +
- +
-  * **Lauflabor Best Student Thesis Award 2018** Apply now until June 30, 2019. Click here for details: {{ :ll02_best_thesis_award18.pdf | Flyer }} +
- +
-  * {{::ansymb_logo_i.png?90 | Teaching course ANSYMB II}} **Running this summer term!** [[http://www.ansymb.tu-darmstadt.de/|   Analysis and Synthesis of Human Movements]]+
 ====== Pick of the Month  ====== ====== Pick of the Month  ======
  
Line 47: Line 41:
 Lower limb exoskeletons require the correct support magnitude and timing to achieve user assistance. This study evaluated whether the sign of the angular velocity of lower limb segments can be used to determine the timing of the stance and the swing phase during walking. We assumed that stance phase is characterized by a positive, swing phase by a negative angular velocity. Thus, the transitions can be used to also identify heel-strike and toe-off. Thirteen subjects without gait impairments walked on a treadmill at speeds between 0.5 and 2.1 m/s on level ground and inclinations between −10 and +10°. Kinematic and kinetic data was measured simultaneously from an optical motion capture system, force plates, and five inertial measurement units (IMUs). These recordings were used to compute the angular velocities of four lower limb segments: two biological (thigh, shank) and two virtual that were geometrical projections of the biological segments (virtual leg, virtual extended leg). We analyzed the reliability (two sign changes of the angular velocity per stride) and the accuracy (offset in timing between sign change and ground reaction force based timing) of the virtual and biological segments for detecting the gait phases stance and swing. The motion capture data revealed that virtual limb segments seem superior to the biological limb segments in the reliability of stance and swing detection. However, increased signal noise when using the IMUs required additional rule sets for reliable stance and swing detection. With IMUs, the biological shank segment had the least variability in accuracy. The IMU-based heel-strike events of the shank and both virtual segment were slightly early (3.3–4.8% of the gait cycle) compared to the ground reaction force-based timing. Toe-off event timing showed more variability (9.0% too early to 7.3% too late) between the segments and changed with walking speed. The results show that the detection of the heel-strike, and thus stance phase, based on IMU angular velocity is possible for different segments when additional rule sets are included. Further work is required to improve the timing accuracy for the toe-off detection (swing).  Lower limb exoskeletons require the correct support magnitude and timing to achieve user assistance. This study evaluated whether the sign of the angular velocity of lower limb segments can be used to determine the timing of the stance and the swing phase during walking. We assumed that stance phase is characterized by a positive, swing phase by a negative angular velocity. Thus, the transitions can be used to also identify heel-strike and toe-off. Thirteen subjects without gait impairments walked on a treadmill at speeds between 0.5 and 2.1 m/s on level ground and inclinations between −10 and +10°. Kinematic and kinetic data was measured simultaneously from an optical motion capture system, force plates, and five inertial measurement units (IMUs). These recordings were used to compute the angular velocities of four lower limb segments: two biological (thigh, shank) and two virtual that were geometrical projections of the biological segments (virtual leg, virtual extended leg). We analyzed the reliability (two sign changes of the angular velocity per stride) and the accuracy (offset in timing between sign change and ground reaction force based timing) of the virtual and biological segments for detecting the gait phases stance and swing. The motion capture data revealed that virtual limb segments seem superior to the biological limb segments in the reliability of stance and swing detection. However, increased signal noise when using the IMUs required additional rule sets for reliable stance and swing detection. With IMUs, the biological shank segment had the least variability in accuracy. The IMU-based heel-strike events of the shank and both virtual segment were slightly early (3.3–4.8% of the gait cycle) compared to the ground reaction force-based timing. Toe-off event timing showed more variability (9.0% too early to 7.3% too late) between the segments and changed with walking speed. The results show that the detection of the heel-strike, and thus stance phase, based on IMU angular velocity is possible for different segments when additional rule sets are included. Further work is required to improve the timing accuracy for the toe-off detection (swing). 
  
-For further publications of the autohr please check: [[https://www.researchgate.net/profile/Martin_Grimmer3|ResearchGate]], [[https://scholar.google.de/citations?hl=de&user=gDF_uHUAAAAJ&view_op=list_works&sortby=pubdate|Google Scholar]] or [[https://orcid.org/0000-0003-1921-1433|ORCID]]+For further publications of the autohr please check: [[https://www.researchgate.net/profile/Martin_Grimmer3|ResearchGate]], [[https://scholar.google.de/citations?hl=de&user=gDF_uHUAAAAJ&view_op=list_works&sortby=pubdate|Google Scholar]], [[https://orcid.org/0000-0003-1921-1433|ORCID]] or [[https://loop.frontiersin.org/people/390560/overview|LOOP]]
 \\ \\
  
  
 [[publications:publications_podcasts_pick_of_the_month|Read previous news...]] [[publications:publications_podcasts_pick_of_the_month|Read previous news...]]