Described is a device for marking a survey object. The device comprises a base having a bottom plate attachable to the survey object, and a rotary plate disposed on the bottom plate and rotatable relative thereto about a first axis, a single support arm projecting from and rotationally fixed relative to the rotary plate, and a survey marker releasably attached to and rotatable relative to the free end of the support arm about a second axis that is perpendicular to the first axis.

A marking apparatus includes a marking apparatus main body including a target, a traveling mechanism for automatically traveling on a traveling surface, and a printer, and a control unit configured to control the printer and the mechanism. The control unit controls the traveling so that the mechanism automatically travels along a set traveling route, the control unit compares position coordinates of the marking apparatus main body obtained from three-dimensional position coordinates of the target during traveling input at predetermined intervals with the traveling route, and corrects traveling to eliminate a deviation from the traveling route, the control unit controls the printer so as to print the marking information set at a position corresponding to the position coordinates of the marking apparatus main body, and traveling route data setting the traveling route and marking information data defining the marking information are created based on CAD design data.

A marking apparatus includes a marking apparatus main body including a target, a traveling mechanism for automatically traveling on a traveling surface, and a printer, and a control unit configured to control the printer and the mechanism. The control unit controls the traveling so that the mechanism automatically travels along a set traveling route, the control unit compares position coordinates of the marking apparatus main body obtained from three-dimensional position coordinates of the target during traveling input at predetermined intervals with the traveling route, and corrects traveling to eliminate a deviation from the traveling route, the control unit controls the printer so as to print the marking information set at a position corresponding to the position coordinates of the marking apparatus main body, and traveling route data setting the traveling route and marking information data defining the marking information are created based on CAD design data.

A target support tool includes: a base member including a first arm and a second arm connectable to each other to form a bent therebetween; a magnetic support part at least on the first arm; and a retroreflector at the bent of the base member.

An absolute coordinate acquisition method is an absolute coordinate acquisition method for acquiring absolute coordinates of an underground pipeline, the method including: a marking step S101 of setting a plurality of reference points on a road surface and setting a measurement point on a pipeline installed inside an excavated ditch; a measurement step S102 of measuring absolute coordinates of the reference points; a relative position calculation step (S103 to S105) of calculating relative positions of the reference points and the measurement point to a reference position; and an absolute coordinate calculation step S106 of calculating absolute coordinates of the measurement point based on the absolute coordinates of the reference points and the relative positions of the reference points and the measurement point.

An absolute coordinate acquisition method is an absolute coordinate acquisition method for acquiring absolute coordinates of an underground pipeline, the method including: a marking step S101 of setting a plurality of reference points on a road surface and setting a measurement point on a pipeline installed inside an excavated ditch; a measurement step S102 of measuring absolute coordinates of the reference points; a relative position calculation step (S103 to S105) of calculating relative positions of the reference points and the measurement point to a reference position; and an absolute coordinate calculation step S106 of calculating absolute coordinates of the measurement point based on the absolute coordinates of the reference points and the relative positions of the reference points and the measurement point.

An optical detection device of detecting a distance relative to a target object includes a substrate, an optical sensor and a processor. The optical sensor is disposed on the substrate and adapted to capture an image about the target object. The processor is disposed on the substrate and electrically connected with the optical sensor. The processor is adapted to mark a first region and a second region within the image for acquiring first quantity of the first region and second quantity of the second region, and compare the first quantity with the second quantity for determining whether the distance is varied to a predefined condition.

A head-mounted display device has more convenient functions, which is usable in, e.g., surveying. An eyeglass display device includes a display unit and an operation content receiving unit. The display unit is configured to be placed on the head of a user and to be viewed by the user. The operation content receiving unit receives content of operation performed by the user. The display unit displays an image that shows a location relationship between positioning information of a target positioned by a location measuring device by using laser light and a predetermined placement planned location of the target. Multiple coordinate systems are prepared for a coordinate system of the displayed image. The operation content receiving unit receives designation of one coordinate system from among the multiple coordinate systems by the user.

A head-mounted display device has more convenient functions, which is usable in, e.g., surveying. An eyeglass display device includes a display unit and an operation content receiving unit. The display unit is configured to be placed on the head of a user and to be viewed by the user. The operation content receiving unit receives content of operation performed by the user. The display unit displays an image that shows a location relationship between positioning information of a target positioned by a location measuring device by using laser light and a predetermined placement planned location of the target. Multiple coordinate systems are prepared for a coordinate system of the displayed image. The operation content receiving unit receives designation of one coordinate system from among the multiple coordinate systems by the user.

A target device, which allows a sufficient amount of reflected light to be obtained from an end portion, is provided and includes a measurement section. In the target device, a retroreflective layer in which a plurality of retroreflective elements are arranged on the entire circumference in a circumferential direction about an axis is formed on at least part of the outer peripheral surface of the measurement section. The retroreflective layer is formed into an uneven shape in which a distance from the axis changes along the entire circumference in the circumferential direction.