A pendulum-based laser leveling device comprises a micro controller unit connected to a shock sensor for sensing a shock experienced by the laser leveling device. The micro controller unit is configured to send out a warning message when the magnitude of the shock sensed by the shock sensor exceeds a shock threshold.

A non-electronic head-worn system for providing visual inertial head orientation information to a person is disclosed. The system comprises a head-worn unit that displays at least one orientation reference symbol to the person wearing the unit wherein the orientation reference symbol stays in a fixed visual position for the person when the person's head changes orientation. The system comprises an optical element located in the optical path between the user's eye and the orientation reference symbol, such as a lens, mirror, a prism, a beam splitter, a retro-reflector, or any other device or medium that can change the appearance or apparent location of an image. The system further comprises a pitch indicator that gives visual pitch information to the person and/or a roll indicator that gives visual roll information to the person. The pitch indicator and the roll indicator are responsive to a pendulum, a rolling element, or a fluid in a reservoir. The pitch element and the roll element do not use electricity or electronics.

A non-electronic head-worn system for providing visual inertial head orientation information to a person is disclosed. The system comprises a head-worn unit that displays at least one orientation reference symbol to the person wearing the unit wherein the orientation reference symbol stays in a fixed visual position for the person when the person's head changes orientation. The system comprises an optical element located in the optical path between the user's eye and the orientation reference symbol, such as a lens, mirror, a prism, a beam splitter, a retro-reflector, or any other device or medium that can change the appearance or apparent location of an image. The system further comprises a pitch indicator that gives visual pitch information to the person and/or a roll indicator that gives visual roll information to the person. The pitch indicator and the roll indicator are responsive to a pendulum, a rolling element, or a fluid in a reservoir. The pitch element and the roll element do not use electricity or electronics.

A pitch measuring device for checking a positioning precision of an operating spindle or an operating table of a machine, e.g. of a NC machine tool moving along an at least two dimensional movement path, the pitch measuring device including a measuring device including a rotary encoder and an electronics unit detecting an angular position of a housing base element relative to a housing top element wherein the measuring device is attachable at a machine arm receiving the operating spindle or at a machine table. Additionally a pendulum element can be used that is connected in a rigid manner with the measuring device and which includes a pendulum element with an integrated first inclination sensor which is supplemented by a second inclination sensor which is directly attachable at frame element of the machine.

A frame which has a wire extending across a rear of the frame is hung on a wall by an integral flexible spring member shaped to define a center mounting plate fastened to lie flat on the wall and a spring strap standing at right angles to the plate with a pair of arms each extending outwardly from the mounting plate along the wall to a respective side of the mounting plate. The arms receive and locate the wire extending along the arms and depending from ends of the arms to the sides of the frame. The arms can flex and the arms allow longitudinal movement of the wire along the arms to allow movement of the frame side to side relative to the mounting plate. A stiffening rod can be inserted onto the strap.

A state visualizer according to one aspect of the present disclosure includes an optical member including a fixed part that has a fixed relative positional relationship with an object to be measured and a movable part that is movably supported by the fixed part and keeps a constant angle with respect to a gravity direction, the optical member retroreflecting a light or an electromagnetic wave in a case where the fixed part and the movable part are in a predetermined positional relationship. The optical member changes an intensity of the light or the electromagnetic wave reflected in a retroreflection direction in accordance with a change of a relative positional relationship between the fixed part and the movable part.

A device for measuring an inclination of a green in a golf course. The device includes: a rotation member (200) having a weight member (210) provided eccentrically relative to a central axis of the rotation member such that the rotation member (200) freely rotates around a rotation shaft (220), the rotation member (200) having horizontal and vertical measurement lines; a first casing (110) having an accommodation space (112); and a second casing (120) fitted over the first casing (110), the second casing (120) having first rotation graduations, a horizontal judge line (h) and a vertical judge line (v), wherein the rotation member (200) comes into close contact with both the first casing (110) and the second casing (120), and then is stopped by a pressure generated between the first and second casings or by simultaneously pressing both a flange (224) of the rotation shaft and the first casing (110).

A device for measuring an inclination of a green in a golf course. The device includes: a rotation member (200) having a weight member (210) provided eccentrically relative to a central axis of the rotation member such that the rotation member (200) freely rotates around a rotation shaft (220), the rotation member (200) having horizontal and vertical measurement lines; a first casing (110) having an accommodation space (112); and a second casing (120) fitted over the first casing (110), the second casing (120) having first rotation graduations, a horizontal judge line (h) and a vertical judge line (v), wherein the rotation member (200) comes into close contact with both the first casing (110) and the second casing (120), and then is stopped by a pressure generated between the first and second casings or by simultaneously pressing both a flange (224) of the rotation shaft and the first casing (110).

The invention discloses a pointer type angle measuring device, comprising a shell consisting of a front cover and a rear cover, windows respectively arranged on the front cover and the rear cover, respectively; a front transparent cover and a rear transparent cover respectively arranged on the windows of the front cover and the rear cover; a pointer, arranged within an inner cavity of the shell inside the front transparent cover and the rear transparent cover; a dial of circular shape, fixed at the outer edge of the windows on the shell. The double-sided readout pointer type angle measuring device with lighting of the invention is convenient to be used in measurement and correction of horizontal and vertical angles of objects when it is inconvenient to be read from single side.

The invention discloses a pointer type angle measuring device, comprising a shell consisting of a front cover and a rear cover, windows respectively arranged on the front cover and the rear cover, respectively; a front transparent cover and a rear transparent cover respectively arranged on the windows of the front cover and the rear cover; a pointer, arranged within an inner cavity of the shell inside the front transparent cover and the rear transparent cover; a dial of circular shape, fixed at the outer edge of the windows on the shell. The double-sided readout pointer type angle measuring device with lighting of the invention is convenient to be used in measurement and correction of horizontal and vertical angles of objects when it is inconvenient to be read from single side.