Massachusetts Institute of Technology
Sign in

Dynamic Walking 2010. Greg Sawicki. Mechanics and control of a compliant muscle-tendon during cyclic contractions

Compliant mechanical behavior of the lower-limb can capture the basic dynamics of stable walking and running across a range of speeds, but the neuromechanical mechanisms responsible for robust, spring-like limb dynamics are not entirely clear. In order for a compliant muscle-tendon unit to behave similar to an elastic spring, the mechanics of active (muscle fascicles) and passive (series-elastic tendon and aponeurosis) tissues must be appropriately coordinated (i.e. ‘tuned’) within the movement cycle. This ‘tuning’ involves adjusting the pattern of muscle activation to modulate muscle force/stiffness output (via intrinsic force-length and force velocity properties) in order to match the loading profile imposed by the environment through series elastic structures within the muscle-tendon unit. Using bullfrog plantaris muscle-tendon, a servo-controlled muscle ergometer and sonomicrometry, we have developed a novel experimental framework to study the neuromechanics of a compliant muscle -tendon unit in vitro. In our initial experiments we employed classical work-loop techniques to understand how the feedforward (i.e. open-loop) muscle activation pattern (timing, magnitude and duration of stimulation) influences muscle-tendon unit net work output and internal energy exchange between muscle fascicles and series-elastic tissues. First I will present results demonstrating conditions that lead to ‘tuned’ elastic behavior of a compliant muscle-tendon unit. Then I will discuss plans to extend our framework and address the relative roles of neural feedback (length and/or force) and muscle-tendon architecture in stabilizing perturbations to steady-state, ‘tuned’ elastic cycles.

Comments (0)

It looks like no one has posted a comment yet. You can be the first!

You need to log in, in order to post comments.

Dynamic Walking 2010

Dynamic Walking 2010

Category: Education | Updated over 6 years ago

Created
August 04, 2010 16:58
Category
License
All Rights Reserved (What is this?)
Additional Files


Viewed
4295 times

More from Dynamic Walking 2010

Dynamic Walking 2010. Tomomichi Sugihara. Dynamics Morphing Toward Globally Stable Bipedalism

Dynamic Walking 2010. Tomomichi Sug...

Added over 6 years ago | 00:27:34 | 5228 views

Dynamic Walking 2010. Manoj Srinivasan. Observations on the Structure of Optimal Gaits on Various Simple Bipedal Models

Dynamic Walking 2010. Manoj Sriniva...

Added over 6 years ago | 00:29:36 | 5091 views

Dynamic Walking 2010. Rodger Kram. Passive Elastic Running Prostheses; Very Good, But Not Yet Better.

Dynamic Walking 2010. Rodger Kram. ...

Added over 6 years ago | 00:37:55 | 3762 views

Dynamic Walking 2010. Madhusudhan Venkadesan. Role of endurance running in human evolution, and how we ran without cushioned shoes

Dynamic Walking 2010. Madhusudhan V...

Added over 6 years ago | 00:35:29 | 5495 views

Dynamic Walking 2010. Sangbae Kim. Bio-inspired Robot Design for Hyper-Dynamic Locomotion

Dynamic Walking 2010. Sangbae Kim. ...

Added over 6 years ago | 00:31:35 | 9981 views

Dynamic Walking 2010. Anton Shiriaev. VHC Tools for Gait Analysis and Control.

Dynamic Walking 2010. Anton Shiriae...

Added over 6 years ago | 00:34:00 | 5468 views