An example material testing system includes: an actuator configured to control an operator-accessible component of the material testing system; and one or more processors configured to: control the actuator based on a material testing process; determine, based on a plurality of inputs, a state of the material testing system from a plurality of predetermined states, the predetermined states comprising one or more unrestricted states and one or more restricted states; when the state of the material testing system is one of the restricted states, enforce a restriction on the actuator; and in response to completion of an automated material test process involving controlling the actuator, automatically set the state of the material testing system to one of the restricted states.

A personal voltage detection system comprises a garment to be worn by a user and carrying a plurality of electric field sensors each facing a different direction. Each sensor comprises a transducer sensing electric field in transmitting a wireless signal representing field strength for an associated direction. An alert device is in operative communication with the plurality of sensors and comprises a control configured to monitor field strength for each sensor and determine existence of an alarm condition responsive to field strength being above a pre-select level and to generate an alarm signal indicating the associated direction of the alarm condition.

A detection system for detecting a dangerous condition for an operator using a power tool of the type which has an exposed blade relative to a work surface and a protection system for minimizing, if not eliminating the possibility of a user being injured by contacting the blade. In one preferred embodiment of the present invention, a proximity detection system is capable of detecting the presence of a user near the blade of a table saw and a protection system that can either retract the blade below the work surface of the table saw or terminate the drive torque to the blade which can result in rapid stopping of the saw blade by a work piece that is being cut.

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.

Woodworking machines and safety methods for use with those machines are disclosed. The machines include a detection system adapted to detect one or more dangerous conditions and a reaction system associated with the detection system. The reaction system can include an explosive to trigger the system, and also can be configured to retract a cutting tool at least partially away from a cutting region upon detection of a dangerous condition by the detection system.

Throat plates for table saws and table saws including the same are disclosed. In some embodiments, the throat plates and/or saws include at least one securement mechanism adapted to secure and prevent inadvertent removal of the throat plate from the throat of the saw. In some embodiments, at least one of the securement mechanisms also provides a height adjustment mechanism and/or prevents vertical removal of the throat plate. In some embodiments, the throat plate includes an accessory mounting port that provides a portal for accessories, including safety accessories, to extend through the plate from beneath the table of the saw. In some embodiments, the port extends from the plate's outer perimeter to divide the plate's rear end portion into a pair of spaced-apart members. In some embodiments, these members are independently secured to the table saw and retained apart from each other by one or more of the securement mechanisms.

Woodworking machines and safety methods for use with those machines are disclosed. The machines include a detection system adapted to detect one or more dangerous conditions and a reaction system associated with the detection system. The reaction system can include an explosive to trigger the system, and also can be configured to retract a cutting tool at least partially away from a cutting region upon detection of a dangerous condition by the detection system.

A power tool and methods are provided for detecting objects (e.g., flesh or other materials) in the operating path of a power tool's output component (e.g., saw blade or drill bit). An object detection sensor in the power tool generates an output signal indicative of a type of material detected in the operating path of the power tool. A power tool controller receives the object detection sensor output and determines when a material in the operating path of the power tool changes. The controller changes operation of a motor of the power tool (e.g., increasing or decreasing speed or stopping the motor) in response to the detected material change. The object detection sensor may include, for example, an RF sensor, a capacitive sensor, a camera, a conductivity probe, or an ultrasound probe.

A safety device is provided for monitoring at least one machine that has at least one sensor for generating sensor data on the machine and a processing unit for the sensor data that is connected at least indirectly to the sensor and to the machine and that is configured as a runtime environment having at least one computing node and to allow at least one logic unit to run on the computing node, wherein at least one logic unit comprises a safety functional unit for a safety relevant evaluation of the sensor data to output in the case of a safety relevant event a safety signal to the machine for triggering a safety response, In this respect, the processing unit is furthermore configured to generate and resolve logic units and/or to assign them to a computing node.

A safety system in a portable tool (1) includes a pair of electrodes connected to a measurement and assessment unit, the measurement and assessment unit being an integrated circuit touch sensor device provided with a ground connector and with a sense electrode, wherein the ground connector is configured as internal floating ground connected to one electrode, the measurement and assessment unit configured for acquiring a reference capacity value measured between the two electrodes varies by a preset difference threshold with respect to the reference value, the safety signal being sent to a tool deactivation actuator.