An apparatus for determining balance compensation includes a platform, sensors and a processor. The platform is configured for a person to stand on the platform. The sensors are coupled to the platform and measure at least one of a weight and a pressure. The processor determines a balance of the person based on the measurements of the sensors.

A method is provided for evaluating the tension or laxity of the soft tissue surrounding a patient's knee joint. Based on this evaluation, a surgeon may determine a desired resection depth for a knee arthroplasty procedure that will achieve an appropriate spacing between adjacent, articulating components of the knee joint.

Devices, systems, tools and methods are disclosed during diagnosis and treatment of spinal conditions. A cervical plumb line device is disclosed which can be used to produce a measurement of the sagittal vertical axis associated with a target part of a patient's cervical spinal anatomy from two or more radiographic images. Also disclosed is an apparatus for measuring the angulation of a patient's spinal anatomy relative to a cervical plumb line which uses a plurality of bolsters. A device that can be used to assist in implantation of an interbody device during spinal fusion device is also disclosed. Systems which produce geometric data describing optimized spinal fusion geometric at a spine level selected to receive spinal fusion.

Accurate measurement of pupillary distance, PD, is necessary to make prescription eye glasses as well as configuring VR headsets, and using other binocular optical devices. Today, many people are ordering eyeglasses on line and obtaining their PD is often problematic for a number of reasons as the prior art fails to provide consumer friendly PD measurement systems. A disclosed eyeglass frame system comprises reference marks of known locations upon the frames. A smart phone may be used to locate the consumer's pupils, while the consumer is wearing the frames. The consumer's pupils may be marked or tagged upon a digital image of the consumer wearing the frames. By use of angles in the sight lines of the camera lens and other variable values and the known relative distances of the frame markings, a consumer's pupillary distance can be quickly and accurately derived.

The disclosure provides a dynamic interaction-oriented subject's limb time-varying stiffness identification method and device. The method includes: the combination of subject's limb displacement and measured force data or the combination of angle and measured torque data is collected; based on the time-varying dynamic system constructed based on a second-order impedance model, the linear parameter varying method is utilized to substitute the time-varying impedance parameters and reconstruct the restoring force/torque expression; iterative identification is performed on variable weights, dynamic interaction force/torque, and restoring force/torque by using time-varying dynamic parameters based on the dynamic interaction force/torque expression expanded from basis function; the time-varying stiffness is solved by using variable weights and dynamic interaction force/torque according to expression with substituted the time-varying impedance parameters. The disclosure not only improves the accuracy of the time-varying stiffness identification technology but also expands the application scenarios of the time-varying stiffness identification technology.

An exercise form analysis and feedback system (EFAF) including at least one sensor, at least one local movement data receiver, an analysis and feedback processing unit (AFPU) and a feedback display. The EFAF system of the present invention obtains lift movement data through the one or more sensors as lift movements are performed. This lift movement data may, in turn, be transmitted to one or more local movement data receivers such that the AFPU may operate on the lift movement data to provide real-time or near real-time form/technique feedback to the user via a feedback display. The system of the presentation invention uses machine learning techniques to provide feedback on lift quality aspects based on data associated with previous lifts and external data as applicable.

The present application relates to a smart knee joint for a human lower limb exoskeleton, a prosthesis, and an orthosis. The smart knee joint reproduces part or all of the biomechanics of the knee joint of the human body by using a motor driving unit and a controllable elastic energy storage unit based on a magnetorheological damper. The motor driving unit here can be replaced with a controllable damping unit. The smart knee joint is developed for helping amputees or patients with impaired mobility regain/repair natural gaits and also reduce their burden of walking. The motor drive unit operates in a generator mode and an actuator mode. Energy harvesting technologies are exploited to reduce the power consumption of the smart knee joint then to prolong the working time. In addition, the controllable elastic energy storage unit based on the magnetorheological damper can further reduce the energy consumption of the smart knee joint, and also simplify the control of the knee joint.

Systems and methods are described to determine joint center of rotation during a procedure. Joint center measurements may be useful to determine other clinically relevant measurements and/or to assist with replacement surgery.

An apparatus for vision testing comprises a visual test unit (VTU) configured to receive a patients face and perform the vision test on the patient. The VTU includes an internal display configured to generate a light stimulus and a gaze sensor configured to track the eye of the patient. In one aspect, a plurality of VTUs form a system controllable by a common technician to concurrently administer vision tests on different patients. In another aspect, the gaze sensor comprises a camera configured to capture a video of the patients eye displayed to the technician. In another aspect, the VTU is configured to pause testing upon detection of an adverse testing condition such as excessive head tilt or a closed eye. In another aspect, the test display comprises an array of LEDs and a perforated opaque screen to provide sufficient luminance. In another aspect, the VTU comprises a head mounted portion with a pair of focusing lenses and a mirror arranged to transmit light from the test display to the eyepiece and from the eyepiece to the gaze sensor. In another aspect, the VTU includes a patient input device configured to receive input from the patient to signal observance of a light stimulus in the visual field around a fixation point, and the VTU is configured to monitor the patients gaze and pause the test upon detecting that the patients gaze has moved from the fixation point.

The disclosure provides a dynamic interaction-oriented subject's limb time-varying stiffness identification method and device. The method includes: the combination of subject's limb displacement and measured force data or the combination of angle and measured torque data is collected; based on the time-varying dynamic system constructed based on a second-order impedance model, the linear parameter varying method is utilized to substitute the time-varying impedance parameters and reconstruct the restoring force/torque expression; iterative identification is performed on variable weights, dynamic interaction force/torque, and restoring force/torque by using time-varying dynamic parameters based on the dynamic interaction force/torque expression expanded from basis function; the time-varying stiffness is solved by using variable weights and dynamic interaction force/torque according to expression with substituted the time-varying impedance parameters. The disclosure not only improves the accuracy of the time-varying stiffness identification technology but also expands the application scenarios of the time-varying stiffness identification technology.