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Title: Comparison of Proximal Leg Strain in Locomotor Model Organisms Using Robotic Legs
Insects use various sensory organs to monitor proprioceptive and exteroceptive information during walking. The measurement of forces in the exoskeleton is facilitated by campaniform sensilla (CS), which monitor resisted muscle forces through the detection of exoskeletal strains. CS are commonly found in leg segments arranged in fields, groups, or as single units. Most insects have the highest density of sensor locations on the trochanter, a proximal leg segment. CS are arranged homologously across species, suggesting comparable functions despite noted morphological differences. Furthermore, the trochanter–femur joint is mobile in some species and fused in others. To investigate how different morphological arrangements influence strain sensing in different insect species, we utilized two robotic models of the legs of the fruit fly Drosophila melanogaster and the stick insect Carausius morosus. Both insect species are past and present model organisms for unraveling aspects of motor control, thus providing extensive information on sensor morphology and, in-part, function. The robotic models were dynamically scaled to the legs of the insects, with strain gauges placed with correct orientations according to published data. Strains were detected during stepping on a treadmill, and the sensor locations and leg morphology played noticeable roles in the strains that were measured. Moreover, the sensor locations that were absent in one species relative to the other measured strains that were also being measured by the existing sensors. These findings contributed to our understanding of load sensing in animal locomotion and the relevance of sensory organ morphology in motor control.  more » « less
Award ID(s):
Author(s) / Creator(s):
; ; ;
Meder, F.; Hunt, A.; Margheri, L.; Mura, A.; Mazzolai, B.
Date Published:
Journal Name:
Biomimetic and Biohybrid Systems. Living Machines 2023.
Medium: X
Sponsoring Org:
National Science Foundation
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