A method and a device for real-time attitude angle measurement based on the field of view effect of the birefringent crystal are provided. The device includes a high-speed polarization measurement module and an object attitude adjustment module connected to each other. The high-speed polarization measurement module includes a polarizer unit and a real-time polarization analyzer unit, respectively located on two opposite sides of the object attitude adjustment module. The object attitude adjustment module includes an attitude angle controller, a roll angle adjustment unit, a pitch angle adjustment unit, a yaw angle adjustment unit, and a height adjustment unit respectively connected to the attitude angle controller, and a birefringent crystal. The method includes an algorithm for real-time extraction of object attitude angle according to optical parameters measured by the high-speed polarization measurement module, and a method for compensating attitude angle measurement errors.

Disclosed herein is a point determination and projection device configured to automatically detect the location of a point of interest, such as a midpoint or other intermediate point on a surface, and to project light or another image onto such point of interest to indicate its location to a user. In accordance with certain aspects of an embodiment of the invention, the device includes remote distance measurement devices, such as laser distance measurement devices, that measure the distance to, for example, corners of a wall surface, and a digital protractor that measures the angle between the two remote distance measurement devices. Based on those measurements, a processor calculates the location of a predesignated point of interest, such as a midpoint or other intermediate point between the two wall corners, and projects a light or other image toward the location of such midpoint or other intermediate point to indicate such location to a user.

Disclosed herein is a point determination and projection device configured to automatically detect the location of a point of interest, such as a midpoint or other intermediate point on a surface, and to project light or another image onto such point of interest to indicate its location to a user. In accordance with certain aspects of an embodiment of the invention, the device includes remote distance measurement devices, such as laser distance measurement devices, that measure the distance to, for example, corners of a wall surface, and a digital protractor that measures the angle between the two remote distance measurement devices. Based on those measurements, a processor calculates the location of a predesignated point of interest, such as a midpoint or other intermediate point between the two wall corners, and projects a light or other image toward the location of such midpoint or other intermediate point to indicate such location to a user.

An electronic device is provided. The electronic device includes an inertial-measurement unit, an environmental-parameter database, and a computation unit. The inertial-measurement unit is configured to detect inertial information of the electronic device to generate sensor data. The computation unit is configured to perform pose estimation according to the sensor data to obtain a first pose. In response to the electronic device being in a non-moving state, the computation unit performs pose calibration on the first pose according to an environmental parameter in the environmental-parameter database corresponding to a current location at which the electronic device is located.

An electronic device is provided. The electronic device includes an inertial-measurement unit, an environmental-parameter database, and a computation unit. The inertial-measurement unit is configured to detect inertial information of the electronic device to generate sensor data. The computation unit is configured to perform pose estimation according to the sensor data to obtain a first pose. In response to the electronic device being in a non-moving state, the computation unit performs pose calibration on the first pose according to an environmental parameter in the environmental-parameter database corresponding to a current location at which the electronic device is located.

The present disclosure provides a method for measuring an angle and a distance. The method includes: at an initial position, after a laser emitting device aligns with a laser receiving device, recording a first angle and measuring a first distance between the laser emitting device and the laser receiving device; and moving the laser receiving device from the initial position to a first position, and after the laser emitting device realigns with the laser receiving device, recording a second angle and measuring a second distance between the laser emitting device and the laser receiving device. The method for measuring the angle and the distance creatively records the corresponding angle and distance at different positions, respectively, such that the position of the laser receiving device relative to the laser emitting device is accurately determined. In addition, the present disclosure also relates to a method for plotting a trajectory map and a laser ranging system using the above method.

The present disclosure provides a method for measuring an angle and a distance. The method includes: at an initial position, after a laser emitting device aligns with a laser receiving device, recording a first angle and measuring a first distance between the laser emitting device and the laser receiving device; and moving the laser receiving device from the initial position to a first position, and after the laser emitting device realigns with the laser receiving device, recording a second angle and measuring a second distance between the laser emitting device and the laser receiving device. The method for measuring the angle and the distance creatively records the corresponding angle and distance at different positions, respectively, such that the position of the laser receiving device relative to the laser emitting device is accurately determined. In addition, the present disclosure also relates to a method for plotting a trajectory map and a laser ranging system using the above method.

A track geometry measurement system includes a plurality of wheels, a frame, and an inertial measurement unit. The inertial measurement unit is coupled to the frame and includes at least one gyroscope.

A track geometry measurement system includes a plurality of wheels, a frame, and an inertial measurement unit. The inertial measurement unit is coupled to the frame and includes at least one gyroscope.

A system for measuring angle adjustment of a hookspanner wrench to accurately tighten a bearing onto a shaft, the shaft having an adapter sleeve mounted thereon, the adapter sleeve having a threaded and tapered portion. The system including a device providing a hookspanner wrench having a lever arm and an engaging portion, the engaging portion of the hookspanner wrench configured to engage a bearing locking nut, the lever arm configured to mount a storage clamping device fixed thereto, a smartphone secured in place by the storage clamping device, and a specialized application stored on the smartphone that provides a built-in inclinometer and look up data tables.