A sensor positioning device includes an inter-sensor distance measurement jig that measures a distance between two sensors, and is a reference when setting the distance between the two sensors to a target distance, and reference-setting jigs of sensor height position, each including a weight and a weight suspension member, a lengthwise direction of which is in a vertical direction when the weight is suspended, and each performing setting of a distance which is a total of a vertical direction dimension of the weight, a length of the weight suspension member, and a distance from an upper end of the weight suspension member to the sensor such that the distance coincides with a target height of the sensor, when the weight is in contact with a reference surface, in a state where the weight is attached to a sensor holding jig by the weight suspension member.

A sensor positioning device includes an inter-sensor distance measurement jig that measures a distance between two sensors, and is a reference when setting the distance between the two sensors to a target distance, and reference-setting jigs of sensor height position, each including a weight and a weight suspension member, a lengthwise direction of which is in a vertical direction when the weight is suspended, and each performing setting of a distance which is a total of a vertical direction dimension of the weight, a length of the weight suspension member, and a distance from an upper end of the weight suspension member to the sensor such that the distance coincides with a target height of the sensor, when the weight is in contact with a reference surface, in a state where the weight is attached to a sensor holding jig by the weight suspension member.

A system for measuring fence posts in a fence run includes a leading unit and a trailing unit. The leading unit includes a first measurement wire extending through a first rotary encoder and terminating in a second rotary encoder, a second measurement wire terminating in a third rotary encoder, and a third measurement wire terminating in a fourth rotary encoder, as well as a clamp to secure the leading unit to a fence post. The trailing unit includes a first rotary encoder to engage with the first measurement wire of the leading unit and a measurement wire terminating in a second rotary encoder, as well as a clamp to secure the trailing unit to a fence post.

A laser holding device is disclosed including cylindrical or hexagonal tube threaded at both ends and can be constructed of metal or Polyvinyl chloride.

An instrument for determining level or plumb orientations includes an elongated body having a plurality of orientation measurement devices. Each of the orientation measurement devices can indicate either a level or plumb orientation depending on a position of the instrument. The orientation measurement devices each include a chamber having front and rear convex sides, a fluid contained in the chamber, and an air bubble floating in the fluid. The elongated body includes a set of first openings and a set of second openings. The orientation measurement devices are embedded into the elongated body through the first set of openings and the orientation measurement devices each include bubble therein viewable from the front and back of the elongated body. The bubble is also viewable from the top and bottom of the elongated body through the second set of openings.

An advanced monitoring device and an implementation method for a whole-process deformation curve of a surrounding rock during tunnel excavation is disclosed, comprising a steel pipe elastic body, a cathetometer structure and an embedded optical fiber, and an implementation step; the cathetometer is an equidistant series structure, and fixed in the steel pipe; the embedded optical fiber is encapsulated in the surface slot of the steel pipe; the cathetometer and the embedded optical fiber and the steel pipe form a deformation coordination structure, and the deformation of the surrounding rock can be deduced by calculating the variation of the cathetometer and the deformation of the optical fiber. The invention can test and calculate the deformation curve of the surrounding rock in front of the excavation face during tunnel excavation, and provide support for engineering dynamic design, construction and safety.

Level tools and level indicating devices for determining the angle of a vertically oriented object relative to both level and plumb capable of being read without requiring the tool's user to change his or her position or the position of the level tool.

Level tools and level indicating devices for determining the angle of a vertically oriented object relative to both level and plumb capable of being read without requiring the tool's user to change his or her position or the position of the level tool.

A tool for finding a point on the ground that is directly below the bottom dead center of a rotatable drum. The tool includes magnetic wheels that support the weight of the tool as the tool is rolled along the bottom of the drum and a level that indicates when the tool is in the proper position to direct a pointer downwardly to define the point on the ground.

A tool for finding a point on the ground that is directly below the bottom dead center of a rotatable drum. The tool includes magnetic wheels that support the weight of the tool as the tool is rolled along the bottom of the drum and a level that indicates when the tool is in the proper position to direct a pointer downwardly to define the point on the ground.