A sensor signal conditioning circuit of a machinery health monitoring module is disposed between a machine sensor and an analog-to-digital converter (ADC). The circuit includes a sensor interface connector, first and second operational amplifiers, a Nyquist filter, and first and second gain flattening feedback networks. The interface connector can connect to multiple types of sensors for monitoring various machine characteristics. The output of the first operational amplifier is coupled to the positive input of the ADC, and the output of the second operational amplifier is coupled to the negative input of the ADC. The first operational amplifier provides a high impedance differential interface to the analog sensor signal and a low impedance interface to the positive input of the ADC. The second operational amplifier provides an inverted copy of a signal at the positive input of the ADC and a low impedance interface to the negative input of the ADC.

A sensor signal conditioning circuit of a machinery health monitoring module is disposed between a machine sensor and an analog-to-digital converter (ADC). The circuit includes a sensor interface connector, first and second operational amplifiers, a Nyquist filter, and first and second gain flattening feedback networks. The interface connector can connect to multiple types of sensors for monitoring various machine characteristics. The output of the first operational amplifier is coupled to the positive input of the ADC, and the output of the second operational amplifier is coupled to the negative input of the ADC. The first operational amplifier provides a high impedance differential interface to the analog sensor signal and a low impedance interface to the positive input of the ADC. The second operational amplifier provides an inverted copy of a signal at the positive input of the ADC and a low impedance interface to the negative input of the ADC.

A sensor power controlling circuit of a machinery health monitoring module includes (1) a positive voltage input for receiving a positive voltage from a galvanically isolated voltage source within the machinery health monitoring module, (2) a sensor power connecter for providing power to a machine sensor, (3) a push-pull comparator having a positive input, a negative input, and an output, (4) a first resistor, (5) a PNP transistor, and (6) a first capacitor. A sensor signal conditioning circuit of the machinery health monitoring module is disposed between a machine sensor and an analog-to-digital converter (ADC). The sensor signal conditioning circuit includes a sensor interface connector, a first and second operational amplifier, a passive Nyquist filter, and first and second gain flattening feedback networks.

A sensor power controlling circuit of a machinery health monitoring module includes (1) a positive voltage input for receiving a positive voltage from a galvanically isolated voltage source within the machinery health monitoring module, (2) a sensor power connecter for providing power to a machine sensor, (3) a push-pull comparator having a positive input, a negative input, and an output, (4) a first resistor, (5) a PNP transistor, and (6) a first capacitor. A sensor signal conditioning circuit of the machinery health monitoring module is disposed between a machine sensor and an analog-to-digital converter (ADC). The sensor signal conditioning circuit includes a sensor interface connector, a first and second operational amplifier, a passive Nyquist filter, and first and second gain flattening feedback networks.

A universal sensor interface for a machine data acquisition system includes a sensor power control circuit that: (1) provides a fast and accurate limiting response to a short-circuit fault, (2) survives and automatically recovers from multiple concurrent continuous short-circuit faults with no interruption to the electrical and thermal integrity of the acquisition system, (3) reduces power consumption/dissipation when in a faulted condition, (4) isolates adverse effects of a faulted channel from uninvolved channels, (5) isolates adverse effects of loose wiring termination chatter from uninvolved channels, (6) protects against adverse effects resulting from hot wiring of sensors, (7) protects the acquisition system against reasonably anticipated installation wiring errors, and (8) minimizes the availability of spark-inducing energy to the data acquisition system.

A system and method for calibrating the gap between a 3D printer extruder nozzle and build platform are disclosed. To calibrate, the build platform is moved laterally in the horizontal plane and the extruder nozzle is moved downward toward the build platform. While moving the nozzle downward, the velocity of the build platform or the power required to move the build platform in the horizontal plane is monitored. A drop in velocity or an increase is power required to move the build platform is detected when the extruder nozzle contacts the build platform due to kinetic friction. The vertical height of the extruder nozzle is then set or calibrated relative to the build platform based on the position of the extruder nozzle when the contact was detected.

A grid plate encoder based positioning system (1) for positioning of an element is provided, the positioning system (1) comprises a grid plate (2) with a grid plate surface (21); an encoder unit (3) with one or more optical sensors (31) for sensing a grid plate surface pattern (23) of the grid plate surface (21); an input (7) to receive coordinates (Xd, Yd) specifying a desired position of the element; a mapping unit (8) to compute compensated coordinate data (Xa, Ya) corresponding to estimated position data expected from the encoder unit (3) when the element is positioned at a desired position (Xd, Yd) specified by the setpoint coordinates; a feedback control unit (9) providing the compensated coordinate data (Xa, Ya) as a setpoint (Xs, Ys) to a positioning unit (12), with feedback control based on the estimated position data obtained from the encoder unit.

Additionally, a grid plate encoder based positioning method and a method for computing compensation data are provided.

A universal sensor interface for a machine data acquisition system includes a sensor power control circuit that: (1) provides a fast and accurate limiting response to a short-circuit fault, (2) survives and automatically recovers from multiple concurrent continuous short-circuit faults with no interruption to the electrical and thermal integrity of the acquisition system, (3) reduces power consumption/dissipation when in a faulted condition, (4) isolates adverse effects of a faulted channel from uninvolved channels, (5) isolates adverse effects of loose wiring termination chatter from uninvolved channels, (6) protects against adverse effects resulting from hot wiring of sensors, (7) protects the acquisition system against reasonably anticipated installation wiring errors, and (8) minimizes the availability of spark-inducing energy to the data acquisition system.