Abstract: According to some embodiments, a device for sensing neuromuscular signals is provided. The device may comprise a plurality of signal electrodes aligned along an interior portion of a wearable structure, each signal electrode being configured to detect neuromuscular signals. The device may comprise a plurality of amplifiers, wherein each amplifier includes (i) a first input operatively coupled to a corresponding signal electrode, (ii) an inverting input, and (iii) an output corresponding to a neuromuscular signal channel. The device may comprise one or more buffers configured to tap a voltage at the inverting input of a respective amplifier of the plurality of amplifiers. The device may comprise circuitry configured to operatively couple a plurality of outputs of the plurality of amplifiers to generate a common mode reference signal, wherein the common mode reference signal is provided to the inverting input of one or more amplifiers of the plurality of amplifiers.

Abstract: Methods and systems for ground tracking and current compensation for biosensing systems are described. In one aspect, a wearable device includes a wearable structure configured to be worn by a user, the wearable structure having an interior surface and an exterior surface, the interior surface being configured to face a user's skin while the wearable device is being worn by the user. The wearable device further includes an electrode at a first position on the interior surface, the electrode configured to detect biopotential signals of the user; and a reference electrode at a second position on the interior surface. The wearable device is configured to (i) measure, via the reference electrode, a difference between a ground potential of the wearable device and a body potential of the user, and (ii) compensate for the difference in processing of the biopotential signals detected by the electrode.

Abstract: An arm-wearable device for sensing neuromuscular signals using a shared reference electrode that is shared between two or more electrodes is provided. The arm-wearable device includes a structure configured to be worn by a user, the structure having an interior surface configured to contact a user's skin when the arm-wearable device is donned by the user. The arm-wearable device includes a first electrode, a second electrode, and a shared reference electrode, each electrode contacts the user's skin above respective neuromuscular pathways of the user when the wearable structure is worn by the user. The first and second electrodes detect neuromuscular signals and the shared reference electrode detects a reference neuromuscular signal. The arm-wearable device includes circuitry configured to compare the neuromuscular signals and the reference neuromuscular signal to determine a motor action that the user intends to perform with their hand.

Abstract: Disclosed herein are methods, systems, apparatuses, and media for sensing neuromuscular signals. In one example, a device for sensing neuromuscular signals comprises a wearable structure. The device includes a plurality of signal electrodes aligned along an interior portion of the wearable structure, each signal electrode configured to detect neuromuscular signals. The device further includes a plurality of amplifiers corresponding to the plurality of signal electrodes, wherein an amplifier has: a first input operatively coupled to a corresponding signal electrode; a second input; and an output corresponding to a neuromuscular signal channel. The device further includes circuitry configured to generate a common mode reference signal directly or indirectly based on signals from one or more electrodes, wherein the second input of each amplifier of the plurality of amplifiers is configured to receive the common mode reference signal or a signal based on the common mode reference signal.

Abstract: The disclosure provides electrically conductive elastomers.