Abstract: A power tool (200) includes a moving implement (222) and an ultrasonic transducer (226) that emits ultrasonic signals and receives echo return signals from an object (224, 229) that reflects the ultrasonic signals. A controller (240) identifies a distance between the implement and the object and identifies a type of the object based on the echo return signals from the object. The controller activates an implement arrest mechanism (236) in response to the distance between the object and the ultrasonic transducer being less than a predetermined threshold and the type of the object corresponding to a portion of a human body.

Abstract: A method for measuring brush wear in a motor of a saw includes generating, with a sensor connected to a brush in a motor of the saw, a first signal corresponding to a level of wear in the brush and identifying, with a controller, a level of wear for the brush with reference to the first signal. The method further includes generating, with the controller and a user interface device, an output requesting replacement of the brush in response to the identified level of wear exceeding a predetermined threshold.

Abstract: A method for secure access control to a power tool enables secure access to an embedded computing device in the power tool from a web application in another computer that is connected to the power tool via a USB or other suitable peripheral data connection in a workshop environment. The access control enables authorized parties to perform repair and diagnostic procedures on the power tools based on specific user roles while denying access to unauthorized parties.

Abstract: A method of operating a power tool identifies motion of an implement in a power tool. The method includes obtaining a plurality of samples of an electrical signal that passes through the implement, identifying a parameter for the plurality of samples corresponding to a variation in values of predetermined groups of samples in the plurality of samples, updating a status for the implement with a first status indicating that the implement is not moving with reference to the identified parameter being less than a predetermined threshold, and updating a status for the implement with a second status indicating that the implement is moving with reference to the identified parameter being greater than the predetermined threshold.

Abstract: A method for detection of false positive condition that an object is in contact with an implement in a power tool includes sampling an electrical signal received from the implement, identifying in-phase and a quadrature components of the sampled electrical signal, identifying a magnitude of each of the samples with reference to the in-phase component and the quadrature component for the samples, detecting an object approaching the implement with reference to the plurality of samples, identifying a signal-to-noise ratio for the samples, and identifying a false positive condition for the detected object with reference to the identified signal-to-noise ratio for the identified samples.

Abstract: A method for secure access control to a power tool enables secure access to an embedded computing device in the power tool from a web application in another computer that is connected to the power tool via a USB or other suitable peripheral data connection in a workshop environment. The access control enables authorized parties to perform repair and diagnostic procedures on the power tools based on specific user roles while denying access to unauthorized parties.

Abstract: A method of operating a power tool detects human contact with a non-moving implement in the power tool. The method includes generating a series of samples of an electrical signal passing through the non-moving implement, identifying a component for each sample in the series of samples of the electrical signal, identifying a first max?min value corresponding to a first plurality of samples in the series of samples occurring during a first periodic time interval with reference to a difference between a maximum value and a minimum value identified in the components of the first plurality of samples, and identifying human contact with the non-moving implement in response to the first max?min value being greater than a first predetermined threshold.

Abstract: A method for operating a power tool detects human contact with a non-moving implement of the power tool. The method includes sampling an electrical signal that passes through the non-moving implement, identifying in-phase and quadrature phase components for the sample, identifying a first distance between the components of the sample and a centroid of a cluster of samples corresponding to human contact with the non-moving implement, identifying a second distance between the components of the sample and a second centroid identified for another cluster of samples corresponding to no human contact with the non-moving implement, and identifying human contact with the non-moving implement with reference to the first distance being less than the second distance.

Abstract: A power tool (200) includes a moving implement (222) and an ultrasonic transducer (226) that emits ultrasonic signals and receives echo return signals from an object (224, 229) that reflects the ultrasonic signals. A controller (240) identifies a distance between the implement and the object and identifies a type of the object based on the echo return signals from the object. The controller activates an implement arrest mechanism (236) in response to the distance between the object and the ultrasonic transducer being less than a predetermined threshold and the type of the object corresponding to a portion of a human body.

Abstract: A method for measuring brush wear in a motor of a saw includes generating, with a sensor connected to a brush in a motor of the saw, a first signal corresponding to a level of wear in the brush and identifying, with a controller, a level of wear for the brush with reference to the first signal. The method further includes generating, with the controller and a user interface device, an output requesting replacement of the brush in response to the identified level of wear exceeding a predetermined threshold.

Abstract: A power tool includes an actuator that moves an implement, an infrared sensor, and a range sensor. A controller in the power tool receives temperature data and range data corresponding to objects in a region proximate to the implement. If an object in the predetermined has a temperature within a predetermined range and is identified as being within a predetermined minimum distance of the moving implement, then the controller deactivates the actuator to halt the implement.

Abstract: A power tool includes a sensing circuit mounted on a printed circuit card is electrically connected to a switching power supply that supplies electrical power to the sensing circuit. The sensing circuit is not connected to earth ground to enable detection of an operator approaching a moving implement without the operator necessarily being electrically connected to earth ground.

Abstract: A power tool includes an actuator that moves an implement, an infrared sensor, and a range sensor. A controller in the power tool receives temperature data and range data corresponding to objects in a region proximate to the implement. If an object in the predetermined has a temperature within a predetermined range and is identified as being within a predetermined minimum distance of the moving implement, then the controller deactivates the actuator to halt the implement.

Abstract: A method for detection of false positive condition that an object is in contact with an implement in a power tool includes sampling an electrical signal received from the implement, identifying in-phase and a quadrature components of the sampled electrical signal, identifying a magnitude of each of the samples with reference to the in-phase component and the quadrature component for the samples, detecting an object approaching the implement with reference to the plurality of samples, identifying a signal-to-noise ratio for the samples, and identifying a false positive condition for the detected object with reference to the identified signal-to-noise ratio for the identified samples.

Abstract: A method of operating a power tool detects human contact with a non-moving implement in the power tool. The method includes generating a series of samples of an electrical signal passing through the non-moving implement, identifying a component for each sample in the series of samples of the electrical signal, identifying a first max?min value corresponding to a first plurality of samples in the series of samples occurring during a first periodic time interval with reference to a difference between a maximum value and a minimum value identified in the components of the first plurality of samples, and identifying human contact with the non-moving implement in response to the first max?min value being greater than a first predetermined threshold.

Abstract: A power tool includes a sensing circuit mounted on a printed circuit card is electrically connected to a switching power supply that supplies electrical power to the sensing circuit. The sensing circuit is not connected to earth ground to enable detection of an operator approaching a moving implement without the operator necessarily being electrically connected to earth ground.

Abstract: A method for operating a power tool detects human contact with a non-moving implement of the power tool. The method includes sampling an electrical signal that passes through the non-moving implement, identifying in-phase and quadrature phase components for the sample, identifying a first distance between the components of the sample and a centroid of a cluster of samples corresponding to human contact with the non-moving implement, identifying a second distance between the components of the sample and a second centroid identified for another cluster of samples corresponding to no human contact with the non-moving implement, and identifying human contact with the non-moving implement with reference to the first distance being less than the second distance.

Abstract: A method of operating a power tool identifies motion of an implement in a power tool. The method includes obtaining a plurality of samples of an electrical signal that passes through the implement, identifying a parameter for the plurality of samples corresponding to a variation in values of predetermined groups of samples in the plurality of samples, updating a status for the implement with a first status indicating that the implement is not moving with reference to the identified parameter being less than a predetermined threshold, and updating a status for the implement with a second status indicating that the implement is moving with reference to the identified parameter being greater than the predetermined threshold.