Abstract: Disclosed is a robust tactile sensor array that mimics the human fingertip and its touch receptors. The mechanical components are similar to a fingertip, with a rigid core surrounded by a weakly conductive fluid contained within an elastomeric skin. It uses the deformable properties of the finger pad as part of the transduction process. Multiple electrodes are mounted on the surface of the rigid core and connected to impedance measuring circuitry within the core. External forces deform the fluid path around the electrodes, resulting in a distributed pattern of impedance changes containing information about those forces and the objects that applied them. Strategies for extracting features related to the mechanical inputs and using this information for reflexive grip control.

Abstract: Photoplethysmography (PPG) is obtained using one red (e.g., 660 nm) and one infrared (e.g., 880 to 940 nm) light emitting diode with a single photo diode in combination with a pressure transducer thereby allowing both CVP and SpO2 to be measured simultaneously. The system also includes sensors capable of measuring position, angle and/or movement of the sensor or patient. Once the PPG signal is acquired, high pass adaptive and/or notch filtering can be used with one element of the filter from the red and infrared signals used to measure the arterial changes needed to compute SpO2 and the other element of the signal can be used to measure CVP changes.