Biomechanics is a diverse field which focuses on the mechanical nature of living organisms, their means of locomotion and articulation, and the mechanical function of their constituent organs. Biomechanics encompasses the study of both human and animal systems to elucidate their fundamental mechanical principles and to apply those principles to enriching the state-of-the-art of medical technology. AMTI contributes to the foundation of biomechanics by developing and manufacturing multiaxis force platforms, multiaxis transducers, data acquisition instrumentation, motion-control instrumentation, and multiaxis test machines to measure and simulate the forces and motions of the human body. AMTI's force measurement instruments and test machines are installed in thousands of educational and commercial biomechanics laboratories around the world.

Force platforms

AMTI’s force platforms have been used for gait analysis, posturography and human performance evaluation for over 25 years. Some of the earliest gait laboratories in the world were equipped with AMTI force platforms. Since the early days of gait analysis, AMTI has maintained an ongoing research and development effort to ensure our customers that when they purchase an AMTI platform it will represent the state-of-the-art in multiaxis force measurement technology. AMTI manufactures 15 different multiaxis force platform designs optimized for a variety of applications which include: portable static balance platforms, portable gait platforms, high precision multiaxis force plates for gait labs and large working surface force platforms for sports and athletic performance evaluation and training. For more information on our wide variety of force platforms please see our Force Platform pages.

Biomechanics software

AMTI was a forerunner in the introduction of computer aided gait analysis and computer aided balance analysis software in the late 1970’s. Over thirty years of development and fine-tuning has resulted in the world’s most comprehensive biomechanics software for gait and balance analysis. AMTI’s BioAnalysis software provides a comprehensive multi-purpose software suite for gait and balance analysis. Our general-purpose data acquisition package called NetForce provides a convenient interface for the acquisition of gait, balance and sports data and makes an excellent interface for our other multiaxis force transducers as well. Specifically aimed at balance acquisition and analysis are AMTI’s Balance Clinic software for static posturography and Balance Feedback for balance feedback training and diagnostics.

Multiaxis transducers

AMTI manufactures over twenty different multiaxis force transducer designs ranging in capacity from 1 to 3 million pounds. Our multiaxis transducers have been applied in many areas of biomechanics. They have been used for ergonomics, haptics, joint force analysis, tactile and proprioceptive studies, prosthetic testing, and have found applications in motion control and joint motion simulation. AMTI manufactures several specially instrumented ambulatory aids including walkers, canes and crutches which are ideal for training, evaluation, and improvement of the motor skills of persons with ambulatory impairments. Please see our multiaxis force transducer pages for more detailed information.

Simulator machines

Simulation of human joint motion for the purpose of designing, testing, and evaluating prosthetic devices prior to the clinical deployment is essential to minimize risk and maximize the successful outcome of such surgical procedures. AMTI’s multiaxis simulator machines provide the ideal environment on which to conduct in-vitro wear, fatigue, and usability testing of a variety of prosthetic components. AMTI’s twelve station hip simulator machine played a prominent part in the discovery of the fundamental nature of the wear of UHDPE acetabular components and is used world wide for the evaluation of hip implant designs. AMTI’s six station knee simulator machine is also widely used by prosthetic device manufacturers and researchers around the world. These machines provide programmable motion control, which can simulate the subtleties of human joint motion while simultaneously testing six (knee) or twelve (hip) implant components under identical conditions.

AMTI has recently introduced a flexible single station joint simulator machine (Force5) which may be configured for a variety of joint simulation tasks. In its standard configuration, this machine has four degrees of freedom and may be used as a general purpose multiaxis testing machine. With the addition of fixturing and a fifth passive degree of freedom the machine becomes an ideal knee simulator machine which may be programmed to provide either force or displacement control for the AP motion. AMTI’s abduction actuator may be mounted on the machine to provide a programmable abduction axis for hip motion simulation. Other applications include TMJ prosthetic testing, dental implant testing, elbow joint testing and spine component testing.

Motion control

As a result of our simulator machine development efforts AMTI has developed a superlative eight channel DSP based PID controller. This controller is ideal for the development joint motion simulation devices and machines. The instrument includes six channels of precision strain gage inputs optimized to provide feedback from AMTI’s multiaxis force transducers. An additional set of 8 high level analog inputs are available for inputs from displacement measuring sensors such as LVDT’s or potentiometers. Coupled with AMTI’s NetControl software this system provides a virtually turnkey solution for multi-channel, multi-axial motion control as is often necessary in biomechanical testing applications.

Special machines

AMTI is continuously developing custom machines and systems for biomechanical testing. Our specialty is long life machines such as our hip and knee simulator machines. We have also developed multi-belt tread mills, which isolate stride into contralateral components and measure the resulting gait reaction forces on each extremity. If you have a particular machine or system development effort that you would like to undertake please contact us. Our engineers will be happy to discuss your needs with you.

Papers and links

Please check out our links page to view dozens of links to academic and commercial laboratories using AMTI multiaxis force platforms, multiaxis transducers and multiaxis test machines. We hope that these links provide you with good ideas for your own projects and installations.

Selected recent abstracts

If you would like to review some recent work that has been conducted using AMTI force platforms click here. This link displays the abstracts of 28 recent papers on gait and balance which reference AMTI’s force platforms. This is only a small sampling of the recent work in the gait and balance fields in which AMTI is referenced in the publication abstracts. For a relatively complete bibliography please contact us.

National Library of Medicine Pubmed

Much of our biomechanics research is done on line using the National Library of Medicines Medline interface, Pubmed, for quick access to medical literature. We provide the NLM PubMed link here for your convenience. Another extremely valuable service provided by the NLM is the Lonesome Doc document delivery service which is particularly if you are not located near a major medical library. The Lonesome Doc service will deliver papers that you select through Pubmed via mail in a few days. Click on this link to start a Lonesome Doc account: Document delivery services.