The present invention provides, among other things, apparatus and methods of use for treating a subject in need of assistance with breathing. In some embodiments the subject suffers from airflow obstruction. In some embodiments, the subject suffers from chronic obstructive pulmonary disease.

An elongation sensor, which includes an elastic, electrically insulating core, and at least two resistive elements arranged helically around the elastic core in opposite directions and in contact with each other. A wearable article including a flexible support, at least one elongation sensor arranged on the flexible support so as to have a length varying when a wearer of the wearable article breathes or when muscles of the wearer are contracted or relaxed, and at least one flexible strip arranged on the flexible support. Also, detecting breathing of a subject with the wearable article.

Provided according to embodiments of the invention are methods, devices and systems for monitoring respiration. Methods described herein include isolating an isolated DC component signal stream, and optionally an isolated AC component signal stream, from the raw PPG signal; calculating a waveform parameter using at least a portion of the isolated DC component signal stream, and optionally, a corresponding portion of the raw PPG signal stream and/or the isolated AC component signal stream; and monitoring respiration in the individual by analyzing the waveform parameter over time.

An apparatus for monitoring a sleep parameter of a user includes an adhesive pad configured to conform to a surface of the user and a flexible element coupled to the adhesive pad. The flexible element includes a conductive fabric, and exhibits a modified electrical property in response to an applied force. The apparatus also includes a power source electrically coupled to the flexible element, and an electrical circuit electrically coupled to the power source and the flexible conductive element. The electrical circuit is configured to detect, during use, a change in an electrical property of the flexible element.

A breathing rate estimation system includes at least one radar type sensor installed in a monitoring area, an information processing device configured to execute person detection processing of acquiring sensor data output from the sensor and detecting a person present in the monitoring area using the acquired sensor data and breathing rate estimation processing of estimating a breathing rate of the person, and a display device configured to display the breathing rate of the person estimated in the breathing rate estimation processing. The information processing device determines whether the person is in a specific state based on a detection result of the person by the person detection processing, and executes the breathing rate estimation processing when it is determined that the person is in the specific state.