Abstract: Embodiments are disclosed for submersion detection and underwater depth and low-latency temperature estimation. In an embodiment, a method comprises: determining a first set of vertical accelerations obtained from an inertial sensor of a wearable device; determining a second set of vertical accelerations obtained from pressure data; determining a first feature associated with a correlation between the first and second sets of vertical accelerations; and determining that the wearable device is submerged or not submerged in water based on a machine learning model applied to the first feature. In another embodiment, a method comprises: determining a submersion state of a wearable device; and responsive to the submersion state being submerged, computing a forward estimate of water temperature based on measured ambient water temperature at the water surface, a temperature error lookup table, and a rate of change of the ambient water temperature.

Abstract: A phase-locked loop compares the loop output clock with the loop input clock in a digital phase detector to provide lead/lag error signal samples. A microprocessor utilizes the lead/lag error samples to track the input clock in a wideband mode matching the bandwidth of the input and in a very narrow band mode. When the system in which the loop is utilized switches to a new input clock source, the microprocessor resets the loop divider chain so that the loop feedback signal is phase coincident with the input reference. The microprocessor tracks the new clock for a predetermined number of error samples in the wideband mode and statistically estimates, from the samples, the frequency of the input. After the frequency estimation, the microprocessor controls the loop VCO to output the computed frequency and switches to the narrow band tracking mode.

Abstract: A PWM inverter in which the maximum three-phase RMS pole-to-pole output voltage is increased, to more efficiently utilize a fixed DC power supply, by generating substantially sinusoidal changing pole voltages having no values within predetermined zones adjacent to each power supply limit, and by switching each pole voltage to a power supply limit for a predetermined number of electrical degrees during each half cycle, resulting in step changes in the pole voltage waveforms from the substantially sinusoidal changing waveform to a fixed power supply limit.

Abstract: Body-carried equipment, such as a television camera, is supported on a mount that engages the body at a first level, such as the shoulder; and the mount has a forwardly extending "panning" arm for directional control. From the forward end of the arm, an adjustable brace assembly extends (e.g., downwardly) to engage the body at a second level (e.g., waist level) spaced vertically from the first level. Adjustments are provided for elevational angle, tilt and forward-rearward balance of the equipment (camera).