Described herein is a magnetic dendrometer having a frame, a spring-tension mechanism, and a magnet for moving together with the spring-tension mechanism. A magnetic sensor is attached to the frame. The magnetic sensor senses the linear motion of the magnet. This linear motion translates to trackable fluctuations in magnetic field. The magnetic fluctuations are converted to electrical signals by the magnetic sensor. A spring is attached to a free-floating wishbone-style component. The free-floating wishbone-style component is coupled to a slider which has an adjustable, single-contact point with a target (e.g., a vine, a branch, etc.). The frame is a stationary frame that carries the magnetic sensor. The frame connected via the spring to the wishbone/slider combination cooperates with each other for providing linear motion to extend or contract the spring in length directions. The length variations of the dendrometer spring are converted to linear motion of the magnet and then into electronic signals.

Described herein is a magnetic dendrometer having a frame, a spring-tension mechanism, and a magnet for moving together with the spring-tension mechanism. A magnetic sensor is attached to the frame. The magnetic sensor senses the linear motion of the magnet. This linear motion translates to trackable fluctuations in magnetic field. The magnetic fluctuations are converted to electrical signals by the magnetic sensor. A spring is attached to a free-floating wishbone-style component. The free-floating wishbone-style component is coupled to a slider which has an adjustable, single-contact point with a target (e.g., a vine, a branch, etc.). The frame is a stationary frame that carries the magnetic sensor. The frame connected via the spring to the wishbone/slider combination cooperates with each other for providing linear motion to extend or contract the spring in length directions. The length variations of the dendrometer spring are converted to linear motion of the magnet and then into electronic signals.

The measurement apparatus (50) comprises at least one hybrid elastic cable (52) wound around the deformable object (22), and a measurement unit (54) capable of measuring the inductance of a wire of the hybrid elastic cable (52) comprising a conductive material between two reference points (58).

A method for determining a position of a magnet assembly relative to an array of inductive elements arranged adjacent to a magnetically permeable material, the method involving: measuring electrical characteristics of each of one or more inductive elements of the array of inductive elements; and from information derived from the measured electrical characteristics of the one or more inductive elements of the array of inductive elements, determining the position of the magnet assembly relative to the array of inductive elements.

A measuring device including a support base, a movable arm, having an extension prevailing along a longitudinal direction and rotatable with respect to the support base along a rotation axis skewed with respect to the longitudinal direction, a probe constrained to the movable arm, apparatus for measuring oscillation of the movable arm, first magnet including at least one first magnetic element constrained to the movable arm, at least one second magnetic element constrained to the support base and not oscillating with the movable arm, the first magnetic element and the second magnetic element reciprocally movable along a movement trajectory having prevailing extension along the longitudinal direction, the first magnetic element and the second magnetic element exerting magnetic force on each other in at least one position along the movement trajectory.

A measuring device including a support base, a movable arm, having an extension prevailing along a longitudinal direction and rotatable with respect to the support base along a rotation axis skewed with respect to the longitudinal direction, a probe constrained to the movable arm, apparatus for measuring oscillation of the movable arm, first magnet including at least one first magnetic element constrained to the movable arm, at least one second magnetic element constrained to the support base and not oscillating with the movable arm, the first magnetic element and the second magnetic element reciprocally movable along a movement trajectory having prevailing extension along the longitudinal direction, the first magnetic element and the second magnetic element exerting magnetic force on each other in at least one position along the movement trajectory.

In a method of determining a radius or diameter of a train wheel, a camera mounted on a train acquires first and second images (pictures) of first and second objects spaced along a path being traveled by the train. Matches are then determined between the first and second objects appearing in the first and second acquired images and representations (pictures) of the first and second objects appearing in prerecorded images included in a track database that include corresponding first and second geographical locations. A distance L traveled by the train between the first and second geographical locations is determined and a sum C of electrical pulses generated by an encoder coupled to the train wheel during travel of the train the distance L is determined. Based on the distance L and the sum C, a diameter or radius of the wheel is determined.

The present disclosure provides a system, an apparatus and a method for detecting line-attached tools in an above-surface portion of a well for use during well-work overs and/or interventions. The system includes the apparatus which comprises: a body for housing at least one magnetic-field generator and at least one magnetic-field sensor; and a tubular portion that is configured to be housed within the body. The tubular portion has a bore for receiving the line-attached tools and the at least one magnetic-field sensor is configured for detecting changes in the magnetic field caused by the line-attached tool approaching, moving through and/or moving away from the body. The system may further include a processor unit for receiving one or more signals from the at least one magnetic-field sensor and for determining the location and/or one or more dimensions of the line-attached tool while approaching, moving through or moving away from the body.

The present disclosure provides a system, an apparatus and a method for detecting line-attached tools in an above-surface portion of a well for use during well-work overs and/or interventions. The system includes the apparatus which comprises: a body for housing at least one magnetic-field generator and at least one magnetic-field sensor; and a tubular portion that is configured to be housed within the body. The tubular portion has a bore for receiving the line-attached tools and the at least one magnetic-field sensor is configured for detecting changes in the magnetic field caused by the line-attached tool approaching, moving through and/or moving away from the body. The system may further include a processor unit for receiving one or more signals from the at least one magnetic-field sensor and for determining the location and/or one or more dimensions of the line-attached tool while approaching, moving through or moving away from the body.

Generally, a device to measure the circumference of circular objects. Specifically, a device including a pair of slidingly engaged members disposed between a pair of arms configured to be engaged with tread on a tire at about the midline of a wheel, an electrical circuit which varies in output voltage based on the distance between the pair of arms, and a processor communicatively coupled to a non-transitory computer readable medium containing a program which correlates the output voltage of the electrical circuit to a unit measure of distance between the pair of arms and calculates tire circumference.