Enduro's Secure Ambulation Module
From: NASA Tech Briefs - July 2003 - page 18

In the 1980s, James Kerley, a researcher at NASA's Goddard Space Flight
Center in Greenbelt, MD, developed cable-compliant mechanisms for use in
sounding rocket assemblies and robotics. This technology uses short segments
of cable to connect structural elements. But unlike rigid connections, the
configuration of the cable segments allows movement in six directions,
enabling subtle cushioning and twisting, as well as shock absorption. 

Kerley later worked with Goddard's Wayne Eklund and Allen Crane to
incorporate the mechanisms into a walker that supported the pelvis. Suffering
from arthritis himself, Kerley knew that an important part of pain management
was alleviating the weight on the legs. The cable-compliant technology
allowed the harness to control the pelvis, providing support and stability
with compliance that mimicked the movement of the hip joint. 

Through Goddard's Technology Transfer Program, the late Kerley's invention
has been licensed and incorporated into a revolutionary new physical therapy
device manufactured by Enduro Medical Technology of East Hartford, CT. 

S.A.M. Stands Out 

Enduro's new device is the Secure Ambulation Module (S.A.M.), a
rehabilitative device that allows patients with degenerative illness or
traumatic injuries to receive physical therapy in a safe, stable standing
position. These patients include those living with severe arthritis, multiple
sclerosis, ALS (Lou Gehrig's disease), cerebral palsy, or Parkinson's
disease, as well as those recovering from strokes, brain or spinal cord
injuries, hip or knee replacement surgeries, cardiac trauma, and anyone who
can't sustain an upright position on their own. 

The S.A.M. walker is expected to revolutionize physical therapy and
restorative nursing. Said Kenneth J. Messier, president of Enduro and a
licensed nursing home administrator, "In the past, patients needing
ambulation therapy had to be lifted to standing by one or more physical
therapists, and be able to prop themselves up using their arms." This
approach was fraught with the risk of injury for both patients, if they fell,
and therapists, who could suffer back injuries while lifting patients.
"S.A.M. changes all of that," said Messier, "and provides lots of other
benefits."  

The S.A.M. device, like other walkers, consists of a wheeled apparatus that
supports users as they ambulate around a room or down a hallway. S.A.M.'s
unique feature is its harness, which supports the patient's body weight and
controls their pelvis without impeding movement of their hips. Electronic
linear actuators raise and lower the harness, varying the weight that
patients place on their legs. 

An upper-trunk harness can be used to provide additional stability to those
patients with severe balance issues. "S.A.M. gives patients the ability to
stand and walk in a controlled, fall-free environment without the need for
constant attention from a therapist," according to Patrick Summers, who leads
engineering, design, and production of S.A.M. at Enduro. Summers also has
designed, developed, and introduced more than 15 wheelchair innovations. 

The key feature of S.A.M. is the NASA cable-compliant technology that allows
the harness to control the patient's pelvis. Said co-developer Crane, "The
thing that Goddard's technology provides to the walker is the flexibility to
allow the person to walk with normal gait, and yet if that person stumbles,
the device can right them just as a keel keeps a ship upright in a storm."  

The harness is dynamically connected to the Goddard-developed cable-compliant
wire joints. Enduro perfected the harness and added the linear actuators,
finalizing the commercially viable device that provides several benefits: 

    Reduced Patient Injury - The security provided by S.A.M. reduces patient
    injuries from falls and boosts their confidence during therapy. 

    Earlier Rehabilitation - Since they don't have to prop themselves up with
    their arms, patients can begin ambulatory rehab earlier. 

    Better Positioning - Freeing the patients arms and the support of the
    upper-trunk harness allow the upper extremities to be positioned
    correctly during therapy. 

    Longer and Specialized Sessions - S.A.M. can enable patients to have
    longer therapy sessions and more specialized treatment. 

    Reduced Therapist Injury - S.A.M. can reduce the back injuries sustained
    by therapists when bringing a patient to a standing position. 

    Increased Staff Efficiency - One therapist can bring a patient to a
    standing position and can work with more than one patient at a time. 

Caption: The Enduro S.A.M. rehabilitation device is demonstrated.



Secure Ambulation Module (SAM) is a walker with a harness that supports
patients body weight, allowing those who cannot stand independently to
receive physical therapy in a safe, stable, fall-free environment without
constant attention from a therapist. SAMs key feature is Goddard's
cable-compliant joint (CCJ) technology, which allows the harness to control
the patients pelvis. The CCJ technology, which consists of connected cable
segments, provides stability while allowing subtle twisting and cushioning
and providing shock absorption and energy damping. Because of the CCJ
technology, SAM can provide several important benefits, including reduced
injuries for patients and therapists, a faster path to rehabilitation,
significant medical benefits, and increased staff efficiency. 

http://techtransfer.gsfc.nasa.gov/GSFC%20newsletter%20Site/spring_03.htm#spotlightsuccess
