Locomotion Energetics and Assessment Laboratory
The Locomotor Energetics and Assessment Laboratory (LEA) is a 1350 square foot motion analysis laboratory located within the College of Health Professions' Research Building on the campus of the Medical University of South Carolina. The laboratory is a shared resource of the college and is supported in part by the Department of Health Sciences and Research. The lab features equipment capable of collecting kinematic, kinetic, electromyographic, strength, and metabolic data. The motion analysis laboratory is adjacent to a small workshop available for the construction, repair, and alteration of simple mechanical devices.
This lab is shared space between several investigators and collaborators in the Department of Health Sciences and Research within the College of Health Professions.
The LEA lab is designed to study locomotion in individuals with neurological injury. State-of the-art software will provide real time results from inverse dynamic calculations and allow the experimenter to immediately determine the quality of the data being collected in both over ground and treadmill data collections. Real time measurement systems will possibly accommodate biofeedback applications and virtual reality.
The laboratory is designed to meet a number of objectives. The primary objective is to evaluate neurologically injured individuals during walking in a safe environment while taking complex and accurate measurements. These measurements are intended to provide insight into the control mechanism of persons with stroke and spinal cord injury and are then to be related to clinically practical measurements that do not require high cost equipment. The laboratory is also intended to provide post processing capabilities to accommodate diverse application of the data to various studies.
Secondary objectives include:
- The evaluation of the effect of passive exoskeletons on gait,
- Exploring balance (static and dynamic),
- The evaluation of neuromuscular complexity,
- Measuring metabolic cost and mechanical work,
- Exploring the effects of Functional Electrical Stimulation during gait,
- Accommodating the design and testing of Robotic Assistive Devices,
- The development and design of new measurement equipment and methods.
- As well as providing cutting edge research capabilities, the laboratory will also be geared toward educating students in biomechanical research. Computer stations with biomechanical evaluation software will be made available to those students who wish to further pursue this avenue. Computational programming languages will also be made available to engineering students who wish to apply engineering to the advancement of measurement technologies and algorithm development in biomechanics. Students will also be afforded the opportunity to be included in conducting the data collections and/or included in equipment management and control under the supervision of qualified instructors in both the clinical and engineering aspect of the laboratory, respectively.
Instrumented treadmill (Bertec): An instrumented split-belt treadmill with the functionality to measure 3D ground reaction forces and moments such that calculation of the two-dimensional location of the Center of Pressure and the moment about the vertical axis can be made under each foot. The treadmill is mounted flush with the floor to allow for the collection of bilateral three-dimensional ground reaction forces and moments during treadmill and over ground locomotion. A ceiling mounted safety harness is available for subject safety during treadmill walking.
Motion Capture system (PhaseSpace Inc.): A 12 camera optical motion capture system, with two linear detectors in each camera, is utilized to measure subject kinematics (PhaseSpace, San Leandro, CA). The system also utilizes active markers that emit infrared light which are placed on anatomical landmarks of a subject to determine segment size characteristics. It then uses clusters of markers to track the segment motions through 3 dimensional space. The system reports a 3600x3600 pixel resolution (equivalent to 12.4 megapixels of resolution) which equates to sub-millimeter accuracy in the concerned capture volume. The system is controlled with custom prepared software coded in National Instrument’s LabView (Austin, TX) that performs automated filtering (3rd order Butterworth with a 25Hz low pass cutoff) and marker interpolation. Marker data is collected at 60Hz with the system and data is interpolated with a 3rd order spline if markers are not captured for less than 5 data points. Possible non-linearity in the positional error of the markers is accounted for with a calibration prior to each session of data collection. Due to active markers system, data and variables can be processed and calculated autonomously and be available to investigators instantaneously. The system is therefore appropriate for biomechanical data acquisition and can also accommodate real-time biofeedback. Due to the custom software used to control the equipment, the equipment is also easily synchronized with other data collection systems and any custom application can be applied to the system with little effort.
Motion Labs Systems 16 Channel EMG System: The laboratory has a 16-channel MA300-XVI EMG system that includes electrodes with built in pre-amplifiers. Included are pressure sensing footswitches that can indicate specific gait events such as heel strike and toe off.
Instrumented Walkway System (GAIT Rite): The system automates the measuring of spatial and temporal parameters of gait using an electronic walkway connected to a PC. The system contains six sensor pads encapsulated in a roll up carpet to produce an active area 24 inches wide and 168 inches long. The system captures the relative geometry and the applied pressure of each footfall as a function of time, and can accommodate patients using ambulatory aids, such as crutches, canes or walkers.
Force PODS Perturbation System (Aretech): The PODS system is based on a master/slave configuration that maintains tension in a cable between the device and the subject without applying a net force until commanded to do so. The Force Pod can determine the impulse response of a human subject to perturbation in a controlled and safe fashion.