Abstract: An embodiment of the invention includes (a) modeling a first internal force applied to a model of a user's joint based on a first external force externally applied to the joint at a first position; (b) modeling a second internal force applied to the model based on a second external force externally applied to the joint at a second position unequal to the first position; (c) comparing the first and second modeled internal forces; and (d) stimulating the user based on the comparison. Other embodiments are described herein.

Abstract: An embodiment of the invention includes (a) modeling a first internal force applied to a model of a user's joint based on a first external force externally applied to the joint at a first position; (b) modeling a second internal force applied to the model based on a second external force externally applied to the joint at a second position unequal to the first position; (c) comparing the first and second modeled internal forces; and (d) stimulating the user based on the comparison. Other embodiments are described herein.

Abstract: An embodiment of the invention includes (a) modeling a first internal force applied to a model of a user's joint based on a first external force externally applied to the joint at a first position; (b) modeling a second internal force applied to the model based on a second external force externally applied to the joint at a second position unequal to the first position; (c) comparing the first and second modeled internal forces; and (d) simulating the user based on the comparison. Other embodiments are described herein.

Abstract: An embodiment includes simultaneously supplying direct current (DC) energy to recondition cartilage of a knee joint while simultaneously protecting that cartilage by supplying alternating current (AC) energy to stimulate muscle tissue contralateral to the cartilage to at least partially decompress the cartilage and at least partially support the joint. Other embodiments are described herein.

Abstract: In that stimulating muscle within a socket may create additional pressure within the socket that is disrelated to external forces operative on the socket, corruption of pressure measurements within the socket may occur from stimulation, even though negative pressure differential on the side opposing, or furthest from the stimulation area, is explicitly used so as to avoid this corruption. An embodiment of the invention provides removal from the total pressure measurement that portion which is known to be resultant of muscle contraction. This stabilizes overall system control through improving input signal quality. Other embodiments are described herein.

Abstract: Acoustic impulses from a muscle are converted into an electrical signal with a transducer such as a piezo film microphone, and analog or digital signal processing circuitry determines the density of self-similar spectral components of the signal and generating an output signal representative of the contractile force of the muscle based upon the density of the self-similar spectral components. The circuitry is used to determine self-similar spectral components of the signal and the density of those components, and the density is used to provide an output signal filtering. Different embodiments use combinations of filtering, Fourier analysis and correlation or auto-correlation. The self-similar spectral components may be pre-determined or determined through signal processing. The output signal may be used to calculate muscle contractile force, fatigue or other muscle conditions.

Abstract: An embodiment of the invention resides in the apparatus and technique of dynamically measuring and storing a biological condition or disposition during the time that one set of conditions are imposed on a joint or body area and applying closed-loop therapeutic action so as to re-achieve that same biological condition or disposition during a subsequent time that another different set of conditions are imposed. Furthermore, dynamic potentials surrounding said joint or body area may be created, bolstered, and/or modulated through aspects of stimulation applied which are independent of those aspects utilized to counteract force incident on the joint or body area. Other embodiments are described herein.

Abstract: A portable device, with method, advantageously applies dynamic stimulation of enclosed muscle tissue to stabilize a prosthetic socket on a residual limb. Dynamic stimulation is in response to physical conditions such as prosthesis motion, position and/or internal pressures. Tissue volume contained within the socket may be stabilized by varying average stimulation levels in response to internal socket pressure.

Abstract: An embodiment includes simultaneously supplying direct current (DC) energy to recondition cartilage of a knee joint while simultaneously protecting that cartilage by supplying alternating current (AC) energy to stimulate muscle tissue contralateral to the cartilage to at least partially decompress the cartilage and at least partially support the joint. Other embodiments are described herein.

Abstract: An embodiment of the invention includes (a) modeling a first internal force applied to a model of a user's joint based on a first external force externally applied to the joint at a first position; (b) modeling a second internal force applied to the model based on a second external force externally applied to the joint at a second position unequal to the first position; (c) comparing the first and second modeled internal forces; and (d) simulating the user based on the comparison. Other embodiments are described herein.

Abstract: The primary of a transformer is driven at low voltages to provide high-voltage dynamic drive from the secondary to a load. A high-current source is placed in series with both the transformer secondary and load. At least secondary inductance of the transformer, hence impedance, is controlled through core saturation to transition secondary output to the load between high-voltage dynamic drive inductively coupled from the primary, and high-current drive serially connected through the secondary. Switching between high voltage and high current output is accomplished through the transformer; no additional switching devices need exist in the high-voltage path. Broad voltage and current capabilities of the configuration inexpensively improve transient drive of highly reactive loads.