Leveling method and leveling device

Abstract

A leveling method in a device main unit with tilt sensors, wherein said method comprises a step of obtaining a response delay of said tilt sensors in advance, a step of tilting said device main unit in a first direction so that said tilt sensors detect a first 0 point, a step of tilting said device main unit in a second direction reverse to said first direction so that a second 0 point is detected after said first 0 point has been detected, a step of obtaining a time up to the detection of both 0 points, a step of calculating a driving time to tilt in the first direction further from said second direction based on said time and said response delay, a step of tilting said device main unit for the driving time, a step of maintaining tilting condition for a predetermined time after tilting and a step of converging by performing leveling operation based on detection result of said tilt sensors after the predetermined time passing.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graphic diagram to show output condition of a tilt sensor in leveling operation in an embodiment of the present invention;

FIG. 2 is a flow chart to show the leveling operation in the embodiment of the present invention;

FIG. 3 is a block diagram to show general outline of the embodiment of the present invention;

FIG. 4 is a cross-sectional view of a surveying instrument, i.e. an example of the device, in which the present invention is carried out; and

FIG. 5 is a graphic diagram to show output condition of a tilt sensor in conventional type leveling operation.

Claims

1. A leveling method in a device main unit with tilt sensors, wherein said method comprises a step of obtaining a response delay of said tilt sensors in advance, a step of tilting said device main unit in a first direction so that said tilt sensors detect a first 0 point, a step of tilting said device main unit in a second direction reverse to said first direction so that a second 0 point is detected after said first 0 point has been detected, a step of obtaining a time up to the detection of both 0 points, a step of calculating a driving time to tilt in the first direction further from said second direction based on said time and said response delay, a step of tilting said device main unit for the driving time, a step of maintaining tilting condition for a predetermined time after tilting and a step of converging by performing leveling operation based on detection result of said tilt sensors after the predetermined time passing.

2. A leveling method according to claim 1, wherein the driving speed to tilt in said second direction is ½ of the driving speed to drive in said first direction, and driving speed to tilt further from said second direction to said first direction is the same as the driving speed in said second direction.

3. A leveling method according to claim 1, wherein the driving time to tilt further from said second direction to said first direction is ⅓ of the time for detection of both said 0 points.

4. A leveling method according to claim 1, wherein the time to tilt further from said second direction to the first direction and to maintain the tilting condition after tilting is shorter than 1.6 seconds.

5. A leveling device comprising a device main unit, tilt sensors provided with said device main unit and a motor for tilting and driving said device main unit and a control unit for controlling said motor, wherein said control unit obtains a response delay of said tilt sensors in advance, tilts said device main unit in a first direction so that said tilt sensors detect a first 0 point, tilts said device main unit in a second direction reverse to said first direction so that a second 0 point is detected after said first 0 point has been detected, obtains a time up to the detections of both 0 points, calculates a driving time to tilt in the first direction further based on said time and said response delay, tilts said device main unit for the driving time, maintains tilting condition for a predetermined time after tilting, and converges by leveling operation based on the detection of said tilt sensors after the predetermined time passing.