U.S. patent application number 09/801152 was filed with the patent office on 2001-09-27 for construction equipment control system.
Invention is credited to Kimura, Kazuaki, Ohtomo, Fumio.
Application Number | 20010023766 09/801152 |
Document ID | / |
Family ID | 18583281 |
Filed Date | 2001-09-27 |
United States Patent
Application |
20010023766 |
Kind Code |
A1 |
Ohtomo, Fumio ; et
al. |
September 27, 2001 |
Construction equipment control system
Abstract
The present invention relates to a construction equipment
control system, which comprises a plurality of rotary laser
irradiating systems for forming laser reference planes by
irradiating laser beams by rotary irradiation, a surveying system
for measuring positions of the rotary laser irradiating systems,
and a construction operation system for controlling and operating
construction work of a construction equipment based on said laser
reference planes, wherein said construction operation system
comprises a photodetection sensor for receiving light beams from
said rotary laser irradiating systems as reference positions for
the construction operation, a global positioning system (GPS) for
detecting a position of said construction equipment, and
transmitting means for transmitting detection results of said GPS
to the surveying system, said surveying system comprises
transmitting means for transmitting data relating to the reference
planes to be formed based on the results of measurement and results
of detection of said GPS to said rotary laser irradiating systems,
the rotary laser irradiating systems comprise receiving means, said
receiving means receives data from said transmitting means, the
rotary laser irradiating systems form the laser reference planes
based on said data, and said construction equipment performs
construction work using said laser reference planes as
reference.
Inventors: |
Ohtomo, Fumio; (Tokyo-to,
JP) ; Kimura, Kazuaki; (Tokyo-to, JP) |
Correspondence
Address: |
Kevin S. Lemack
Nields & Lemack
176 E. Main Street - Suite 8
Westboro
MA
01581
US
|
Family ID: |
18583281 |
Appl. No.: |
09/801152 |
Filed: |
March 7, 2001 |
Current U.S.
Class: |
172/4.5 ;
701/50 |
Current CPC
Class: |
E02F 3/847 20130101;
G05D 1/0236 20130101; G05D 1/028 20130101; E02F 3/842 20130101;
G01S 17/86 20200101; G05D 1/0272 20130101; G05D 1/0278 20130101;
G01C 15/004 20130101 |
Class at
Publication: |
172/4.5 ;
701/50 |
International
Class: |
E02F 003/76 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 8, 2000 |
JP |
063408/2000 |
Claims
What is claimed is:
1. A construction equipment control system, comprising a plurality
of rotary laser irradiating systems for forming laser reference
planes by irradiating laser beams by rotary irradiation, a
surveying system for measuring positions of the rotary laser
irradiating systems, and a construction operation system for
controlling and operating construction work of a construction
equipment based on said laser reference planes, wherein said
construction operation system comprises a photodetection sensor for
receiving light beams from said rotary laser irradiating systems as
reference positions for the construction operation, a global
positioning system (GPS) for detecting a position of said
construction equipment, and transmitting means for transmitting
detection results of said GPS to said surveying system, said
surveying system comprises transmitting means for transmitting data
relating to the reference planes to be formed based on results of
measurement and results of detection of said GPS to said rotary
laser irradiating systems, said rotary laser irradiating systems
comprise receiving means, said receiving means receives said data
from said transmitting means, said rotary laser irradiating systems
form said laser reference planes based on said data, and said
construction equipment performs construction work using said laser
reference planes as reference.
2. A construction equipment control system according to claim 1,
wherein said surveying system comprises a operation control system
for controlling construction operation of the construction
equipment, said operation control system is provided with working
data for performing said construction operation, calculates data
for forming said laser reference planes necessary for said
construction operation based on said working data and the position
of the construction equipment determined by said GPS and positions
of said rotary laser irradiating systems measured by said surveying
system, and transmits said data to said rotary laser irradiating
systems, and said laser reference planes necessary for the
construction operation are formed by said rotary laser irradiating
systems.
3. A construction equipment control system according to claim 2,
wherein said working data is height data at a construction
site.
4. A construction equipment control system according to claim 2 or
3, wherein said operation control system is provided with working
route data indicating a route of construction.
5. A construction equipment control system according to claim 4,
wherein said operation control system is provided with tilting data
at a construction site in addition to said construction route data
indicating said the route of construction.
6. A construction equipment control system according to claim 1,
wherein said rotary laser irradiating systems comprise a reflection
unit for reflecting a distance measuring light beam toward an
automatic surveying system, a rotating mechanism for directing the
system itself toward a predetermined direction, a signal receiving
unit for receiving communication data, a tilting mechanism for
tilting said laser reference plane, and a tilt setting unit for
controlling said tilting mechanism and said rotating mechanism so
that said laser reference plane has a tilt angle in a predetermined
direction based on the result received from said signal receiving
unit.
7. A construction equipment control system according to claim 1,
wherein each of said rotary laser irradiating systems further
comprises a lift mechanism, and elevation of said laser reference
plane can be adjusted by said lift mechanism and it is controlled
by said tilt setting unit together with said tilting mechanism and
said rotating mechanism.
8. A construction equipment control system according to claim 1,
wherein said rotary laser irradiating systems synchronize rotation
of laser beams.
9. A construction equipment control system according to claim 1,
wherein said laser beams irradiated from said rotary laser
irradiating systems are independently modulated.
10. A construction equipment control system according to claim 9,
wherein there is provided an arithmetic unit for identifying said
rotary laser irradiating systems based on a laser beam
photodetection signal from said photodetection sensor.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a rotary laser irradiating
system for forming a reference plane in civil engineering work such
as ground leveling work. In particular, the invention relates to a
construction equipment control system utilizing a laser reference
plane to be formed by rotary irradiation of a laser beam for the
purpose of controlling height in ground leveling operation.
[0002] When ground leveling operation for preparing land for
housing lots or for road paving is performed using construction
equipment such as a bulldozer, a grader, etc., a reference for the
ground leveling is needed. In recent years, a system using a laser
beam has become widespread for the purpose of determining height,
which serves as a reference for the ground leveling operation. As
one of the systems using the laser beam, there is a construction
equipment control system which comprises rotary laser irradiating
systems.
[0003] FIG. 8 shows a case where this construction equipment
control system is adopted for a bulldozer.
[0004] In FIG. 8, reference numeral 1 denotes a rotary laser
irradiating system, and 2 a bulldozer. The rotary laser irradiating
system 1 is placed at a predetermined position via a tripod 3 on
the land developed for housing lots. The rotary laser irradiating
system 1 projects a laser beam 4 in a horizontal direction and
rotates the laser beam, and a reference plane is formed by the
laser beam 4.
[0005] The bulldozer 2 has a blade 5, which is supported in such
manner that it can be moved up or down. A pole 6 is erected on the
blade 5, and a level sensor 7 serving as photodetecting means is
mounted on the pole 6. The level sensor 7 receives the laser beam 4
from the rotary laser irradiating system 1 and detects a
photodetecting position. The bulldozer 2 is provided with a control
unit (not shown), which detects a height position of the blade 5
based on a photodetection signal from the level sensor 7 and
controls a height of the bulldozer based on the detection
results.
[0006] As described above, a horizontal reference plane is formed
by the laser beam 4. By keeping a distance between the horizontal
reference plane and a blade tip 5' of the blade 5 to a constant
value, a ground surface can be prepared on horizontal level. Also,
by changing a distance to the blade tip 5', it is possible to
change the height of the leveled ground.
[0007] The laser beam 4 projected from the rotary laser irradiating
system has a limited reaching range due to the limitation of light
intensity. For this reason, in case of a construction site of
relatively small extent, when the rotary laser irradiating system 1
is once set for the operation, the area of the scheduled
construction falls within the range of the laser beam 4. However,
in a construction site of wider extent, it is inconvenient that the
rotary laser irradiating system must be set again and adjusted for
the next operation. Further, in case of a construction with
difference in elevation, the system must be set again, and the
construction operation cannot be carried out continuously and must
be interrupted each time for re-adjustment.
[0008] In case of road construction, road may be curved, or the
laser beam 4 may be cut off by an obstacle such as a mountain or a
hill, etc. In these cases, the rotary laser irradiating system 1
must be moved as the construction operation proceeds, and it must
be newly set again. In addition to the troublesome procedure
related to the re-setting of the system, an error may also occur
during the re-setting.
SUMMARY OF THE INVENTION
[0009] To solve the above problems, it is an object of the present
invention to provide a construction equipment control system, by
which it is possible to perform setting of the reference planes for
wider range using a plurality of rotary laser irradiating systems,
to eliminate troublesome procedure caused by interrupting
construction work in the middle of the work and performing
re-setting, and to prevent occurrence of the error.
[0010] To attain the above object, the construction equipment
control system of the present invention comprises a plurality of
rotary laser irradiating systems for forming laser reference planes
by irradiating laser beams by rotary irradiation, a surveying
system for measuring positions of the rotary laser irradiating
systems, and a construction operation system for controlling and
operating construction work of a construction equipment based on
the laser reference planes, wherein the construction operation
system comprises a photodetection sensor for receiving light beams
from the rotary laser irradiating systems as reference positions
for the construction operation, a global positioning system (GPS)
for detecting a position of the construction equipment, and
transmitting means for transmitting detection results of the GPS to
the surveying system, the surveying system comprises transmitting
means for transmitting data relating to the reference planes to be
formed based on results of measurement and results of detection of
the GPS to the rotary laser irradiating systems, the rotary laser
irradiating systems comprise receiving means, the receiving means
receives the data from the transmitting means, the rotary laser
irradiating systems form the laser reference planes based on the
data, and the construction equipment performs construction work
using the laser reference planes as reference. Also, the present
invention provides a construction equipment control system as
described above, wherein the surveying system comprises a operation
control system for controlling construction operation of the
construction equipment, the operation control system is provided
with working data for performing the construction operation,
calculates data for forming the laser reference planes necessary
for the construction operation based on the working data and the
position of the construction equipment determined by the GPS and
positions of the rotary laser irradiating systems measured by the
surveying systems and transmits the data to the rotary laser
irradiating systems, and the laser reference planes necessary for
the construction operation are formed by the rotary laser
irradiating systems. Further, the present invention provides a
construction equipment control system as described above, wherein
the working data is height data at a construction site. Also, the
present invention provides a construction equipment control system
as described above, wherein the operation control system is
provided with working route data indicating a route of
construction. Further, the present invention provides a
construction equipment control system as described above, wherein
the operation control system is provided with tilting data at a
construction site in addition to the construction route data
indicating the route of construction. Also, the present invention
provides a construction equipment control system as described
above, wherein the rotary laser irradiating systems comprise a
reflection unit for reflecting a distance measuring light beam
toward an automatic surveying system, a rotating mechanism for
directing the system itself toward a predetermined direction, a
signal receiving unit for receiving communication data, a tilting
mechanism for tilting the laser reference plane, and a tilt setting
unit for controlling the tilting mechanism and the rotating
mechanism so that the laser reference plane has a tilt angle in a
predetermined direction based on the result received from the
signal receiving unit. Further, the present invention provides a
construction equipment control system as described above, wherein
each of the rotary laser irradiating systems further comprises a
lift mechanism, and elevation of the laser reference plane can be
adjusted by the lift mechanism and it is controlled by the tilt
setting unit together with the tilting mechanism and the rotating
mechanism. Also, the present invention provides a construction
equipment control system as described above, wherein the rotary
laser irradiating systems synchronize rotation of laser beams.
Further, wherein the laser beams irradiated from the rotary laser
irradiating systems are independently modulated. Also, the present
invention provides a construction equipment control system as
described above, wherein there is provided an arithmetic unit for
identifying the rotary laser irradiating systems based on a laser
beam photodetection signal from the photodetection sensor.
[0011] Because the reference planes can be set using a plurality of
rotary laser irradiating systems, laser reference planes can be
formed for wider area, and continuous construction operation can be
carried out at the construction site where there are differences in
height or there is an obstacle to cut off the laser beam.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a drawing to explain an embodiment of the present
invention;
[0013] FIG. 2 is a plan view showing an arrangement of the
embodiment of the present invention;
[0014] FIG. 3 is a block diagram of the embodiment of the present
invention;
[0015] FIG. 4 is a schematical cross-sectional view of a rotary
irradiation system main unit to be used in the embodiment of the
invention;
[0016] FIG. 5 is a block diagram a rotary irradiation system main
unit to be used in the embodiment of the invention;
[0017] FIG. 6 is a perspective view of a level sensor used in the
embodiment of the present invention;
[0018] FIG. 7 is a plan view of an arrangement of another
embodiment of the present invention; and
[0019] FIG. 8 is a drawing to explain a conventional example.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0020] Detailed description will be given below on embodiments of
the present invention referring to the drawings.
[0021] In FIG. 1 to FIG. 3, the same component as in FIG. 8 is
referred by the same symbol, and detailed description is not given
here.
[0022] The embodiment of the present invention comprises a
plurality of rotary laser irradiation systems 1a, 1b and 1c (3
systems shown in the figure), each of which can form a tilted
reference plane, and an automatic surveying system 10, and a global
positioning system (GPS). By each of the rotary laser irradiating
systems 1a, 1b and 1c, reference planes 11a, 11b and 11c to cover
an extensive area are formed respectively. Civil engineering work
is carried out by a bulldozer 2 using the reference planes 11a, 11b
and 11c as references while the position of the construction
equipment is surveyed using the GPS.
[0023] Within a area of the scheduled construction project, a
plurality of rotary laser irradiation systems 1 are arranged. The
rotary laser irradiation systems 1a, 1b and 1c are separated from
each other by such a distance that the formed reference planes 11a,
11b and 11c are overlapped on each other to a certain extent. The
automatic surveying system 10 is provided at a distance from the
construction area and at a known point. In case it is not a known
point or in case of kinematic surveying, a second GPS receiver 102
is provided. To the automatic surveying system 10, an operation
control system 12 typically represented by a personal computer (PC)
is connected. The second GPS receiver 102 and a radio transceiver
103 are connected to the operation control system 12. The result of
position measurement by the second GPS receiver 102 and the
information received by the radio transceiver 103 are inputted to
the operation control system 12.
[0024] Based on the results of receiving by the second GPS receiver
102 and a first GPS receiver 107 (to be described later) which is
installed on the bulldozer 2, kinematic surveying is performed, and
position measurement for the automatic surveying system 10 and
position measurement for the bulldozer 2 are carried out. The
second GPS receiver 102, the first GPS receiver 107, and the
operation control system 12 make up together a surveying system. A
radio transceiver unit 110 (to be described later) installed on the
bulldozer 2, the first GPS receiver 107, and the radio transceiver
103 make up together a data communication system. The second GPS
receiver 102 and the first GPS receiver 107 make up together a
kinematic surveying system. If accuracy high enough can be
obtained, only the first GPS receiver 107 may be used.
[0025] The results of the calculation at the operation control
system 12 can be transmitted to the radio transceiver 110 via the
radio transceiver 103.
[0026] The operation control system 12 comprises an arithmetic unit
13, a storage unit 14, a display unit 15, and an input unit 16. In
the storage unit 14, there are provided various types of programs
necessary for arithmetic process of data such as tilt angle of each
of the reference planes 11a, 11b and 11c. Also, data such as
topographical data based on the working drawings are set and
inputted. These data include data for the height of the ground with
respect to plane coordinates. And further, data on the position of
the bulldozer 2 based on GPS surveying, and programs for
calculating relative positions of the rotary laser irradiating
system 1 and the bulldozer 2 are set and inputted in the storage
unit 14. Further, machine height of each of the rotary laser
irradiating systems 1, a distance from the blade tip 5' to the
reference position of the level sensor 7, etc. are set and
inputted.
[0027] The automatic surveying system 10 measures the data such as
survey data of position and height. The first GPS receiver 107
obtains position of the bulldozer 2. Based on the survey data, the
position of the bulldozer and, further, height data in the working
drawings, the operation control system 12 calculates a laser
reference plane for controlling the blade tip 5' of the bulldozer
2. The operation control system 12 controls a tilting direction of
each of the rotary laser systems 1a, 1b and 1c via the automatic
surveying system 10 so that a predetermined laser reference plane
is formed.
[0028] Now, description will be given on the automatic surveying
system 10.
[0029] On a tripod 17, a frame stand 19 is placed via a base unit
18 so that it can be rotated around a vertical axis. On the frame
stand 19, a telescope unit 21 is mounted so that it can be rotated
around a horizontal axis. On the base unit 18, a horizontal motor
22 is provided, and an elevation motor 23 is mounted on the frame
stand 19.
[0030] On the frame stand 19, a control unit 24, a rotary driving
unit 25, and a distance measuring unit 29 are mounted. The rotary
driving unit 25 is controlled by the control unit 24, and the
horizontal motor 22 and the elevation motor 23 are driven by the
rotary driving unit 25. A horizontal angle encoder 26 is provided
on a rotary support of the base unit 18, and an elevation angle
encoder 27 is provided on a rotary support of the telescope unit
21. Rotation angle detection signals from the horizontal angle
encoder 26 and the elevation angle encoder 27 are inputted to an
angle measuring unit 28. A horizontal rotation angle and a
horizontal angle with respect to the reference direction of the
frame stand 19 are detected, and an elevation rotation angle and an
elevation angle of the telescope unit 21 are detected. A rotation
angle detection signal from the angle measuring unit 28 is
feedbacked to the control unit 24. The control unit 24 controls an
amount of rotation of each of the horizontal motor 22 and the
elevation motor 23 via the rotary driving unit 25 based on the
rotation angle detection signal.
[0031] The telescope unit 21 comprises a light emitting unit 31, a
modulation circuit 32 and a photodetection unit 33. The light
emitting unit 31 emits a tracing light beam 34 or a distance
measuring light beam 30 toward an object, i.e. toward each of the
rotary laser irradiation systems 1. The modulation circuit 32
modulates either the tracing light 34 or the distance measuring
light 30 based on communication data. By this modulation,
communication data is superimposed either on the distance measuring
light 30 or on the tracing light 34, and optical communication can
be provided to the photodetection side.
[0032] The photodetection unit 33 receives the distance measuring
light reflected from the rotary laser irradiating system 1, and a
photodetection signal is outputted to the distance measuring unit
29. The distance measuring unit 29 surveys a distance to the
object, and the result of the survey is inputted to the control
unit 24.
[0033] Now, description will be given on the rotary laser
irradiating system 1 referring to FIG. 4 and FIG. 5.
[0034] Each of the rotary laser irradiating systems 1 comprises a
tilting mechanism for tilting the irradiating direction of a laser
beam 4 and a control unit for controlling the tilting mechanism. It
can tilt the irradiating direction of the laser beam 4, and a
horizontal reference plane or a tilted reference plane is formed by
the laser beam 4.
[0035] The rotary laser irradiating system 1 comprises a rotary
laser irradiating system main unit 35, and the level sensor 7
(mounted on the bulldozer 2) for detecting the laser beam 4 from
the rotary laser irradiating system main unit 35. The rotary
irradiating system main unit 35 is mounted on a tripod 37 via a
leveling unit 36, which is arranged at lower position.
[0036] Further, the rotary irradiating system main unit 35
primarily comprises a light emitting unit 38 for emitting the laser
beam 4, a rotator 39 for irradiating the laser beam 4 in the
reference plane by rotary irradiation, a rotating unit 41 for
rotating the light emitting unit 38 around the vertical axis, a
tilt setting unit 42 for tilting the light emitting unit 38 around
the horizontal axis and for setting a tilt of the reference plane
formed by the laser beam 4, a tilt detector 43 for detecting tilt
angle, a reflection light receiving unit 44 for receiving an
incident light and for detecting a direction of the incident light,
and the leveling unit 36 for performing the leveling of the rotary
irradiating system main unit 35.
[0037] On the upper surface of the rotary irradiating system main
unit 35 and on an extension from the rotation center of the rotator
39, there are provided a retroreflection prism 45 and a signal
receiver 46. As shown in FIG. 3, the retroreflection prism 45
reflects the tracing light beam 34 and the distance measuring light
beam 30 from the light emitting unit 31 toward the photodetection
unit. The signal receiving unit 46 receives the distance measuring
light beam 30. It detects modulation of the distance measuring
light 30 and detects the communication data superimposed on the
distance measuring light 30.
[0038] The rotary irradiating system main unit 35 has a light
receiving window 47 on it, and the laser beam 4 from the rotator 39
is projected through the light receiving window. The tracing light
34 or the distance measuring light 30 from the automatic surveying
system 10 passes through the light receiving window 47, and it is
received by the reflection light receiving unit 44 installed inside
the rotary irradiating system main unit 35. When the light is
received by the signal receiving unit 46, the photodetection unit
44 detects a direction of the automatic surveying system 10. Based
on the communication data from the automatic surveying system 10,
the direction of the rotary irradiating system main unit 35 is
aligned with the reference direction.
[0039] At the bottom of a casing 48 of the rotary irradiating
system main unit 35, a main unit frame 51 is provided so that it
can be rotated around the vertical axis via a vertical axis unit
49. A rotating unit gear 52 is mounted concentrically with the
vertical axis unit 49, also there is provided a rotating unit
encoder 53. A rotating unit motor 54 is provided at a position
closer to the casing 48, and an output shaft of the rotating unit
motor 54 is engaged with the rotating unit gear 52. When the
rotating unit motor 54 is driven, the main unit frame 51 is rotated
via the rotating unit gear 52. A rotation angle is detected by the
rotating unit encoder 53, and the result of detection is inputted
to a control unit (CPU) 72.
[0040] At the bottom of the casing 48, the leveling unit 36 is
disposed. The leveling unit 36 comprises a fixed based plate 55
fixed on the tripod 37 and leveling screws 56 being placed between
the fixed base plate 55 and the bottom of the casing 48. Three
leveling screws 56 are provided, each at a vertex of a triangle.
The upper end of each of the leveling screws is screwed into the
casing 48, and its lower end is rotatably engaged in the fixed base
plate 55. Each of the leveling screws 56 is connected to a leveling
motor 58 via a gear train 57. When the leveling gear 56 is rotated
by the leveling motor 58 via the gear train 57, a gap between the
casing 48 and the fixed base plate 55 is changed, and the rotary
irradiating system main unit 35 can be tilted in a direction as
desired.
[0041] Tilting of the rotary irradiating system main unit 35 is
detected by tilt sensors 59 and 60 provided on the main unit frame
51. The leveling operation is performed through feedback of the
detection results of the tilt sensors 59 and 60 to the driving of
the leveling motor 58. One of the three leveling screws 56 may not
be used, and this may be used only as a tiltable supporting
point.
[0042] The light emitting unit 38 is rotatably mounted on the main
unit frame 51 via a horizontal tilting shaft 61. A tilting motor 62
is disposed on the main unit frame 51, and the tilting motor 62 and
the tilting shaft 61 are connected with each other via a gear train
63. On the tilting shaft 61, the tilt detector 43 for detecting a
tilt angle of the light emitting unit 38 is mounted. The tilt
detector 43 comprises an encoder, for instance. When the tilting
motor 62 is driven, the light emitting unit 38 can be tilted via
the gear train 63, and the tilt angle is detected by the tilt
detector 43.
[0043] On the upper end of the light emitting unit 38, the rotator
39 is rotatably mounted. The rotator 39 has a scanning gear 64,
which is engaged with a driving gear 66 of a scanning motor 65. The
scanning motor 65 is fixed on the light emitting unit 38. When the
driving gear 66 is driven by the scanning motor 65, the rotator 39
is rotated via the scanning gear 64.
[0044] The rotator 39 deflects an optical axis of the laser beam 4
emitted from the light emitting unit 38 via a pentagonal prism 67
at an angle of 90.degree.. The laser beam 4 is passed through a
projecting window 68 and is rotated so as to form a laser plane.
The pentagonal prism 67 is mounted on a rotary support 69, which is
rotated around the optical axis of the light emitting unit 38, and
the rotary support 69 is connected to the scanning motor 65 via the
scanning gear 64 and the driving gear 66. The rotating condition of
the rotary support 69 is detected by an encoder 71 mounted on the
rotary support 69, and a detection signal of the encoder 71 is
inputted to the control unit 72.
[0045] The tilt angle of the light emitting unit 38 is detected by
the tilt detector 43 mounted on the tilting shaft 61 of the light
emitting unit 38. The tilt detector 43 comprises an encoder, and an
output signal from the encoder is inputted to the control unit 72.
Based on the signal from the tilt detector 43, the control unit 72
calculates tilting of the light emitting unit 38 up to a
predetermined tilt angle. The tilting motor 62 is driven by a
tilting motor driving unit 73. The setting of the tilting can be
achieved by driving the tilting motor 62 until the output of the
tilt detector 43 provides a predetermined tilt angle.
[0046] The reflection light receiving unit 44 may be fixed on the
casing 48, but it is preferably mounted on the light emitting unit
38 so that it can be tilted integrally with the light emitting unit
38.
[0047] Next, description will be given on the reflection light
receiving unit 44.
[0048] At a position facing to the light receiving window 47, a
condenser lens 75 is provided. An incident light to the condenser
lens 75 is converged to a photodetection element 77 via a
reflection mirror 76. A photodetection signal from the
photodetection element 77 is inputted to a reflection light
detector 81. The incident light from the automatic surveying system
10 as detected by the reflection light detector 81 is inputted to
the control unit 72. Also, a signal from the rotating unit encoder
53 is inputted to the control unit 72. The control unit 72 drives a
laser diode 83 via a light emitting element driving unit 82, drives
the scanning motor 65 via a scanning motor driving unit 84, drives
the rotating unit motor 54 via a rotating unit motor driving unit
85, drives the tilting motor 62 via the tilting motor driving unit
73, and drives the leveling motor 58 via a leveling motor driving
unit 86 based on the signals from the tilt sensors 59 and 60.
[0049] Based on the signal from the reflection light detector 81
and a signal from the rotating unit encoder 53, the control unit 72
detects a direction of the automatic surveying system 10 and
calculates in which direction and to how much angle the rotary
irradiating system main unit 35 is rotated.
[0050] Next, the tripod 37 will be described.
[0051] The rotary irradiating system main unit 35 is fixed on a
lift mechanism 87 via the fixed base plate 55, and the lift
mechanism 87 moves the rotary irradiating system main unit 35 up or
down. The tilt mechanism 87 comprises an elevation motor 88, a
driving unit 89 for rotating and driving the elevation motor 88,
and an elevation detection encoder 91 for detecting elevation of
the rotary irradiating system main unit 35, and it can adjust the
position of the rotary irradiating system main unit 35 in a height
direction and can also detect the elevation position.
[0052] Now, the level sensor 7 will be described referring to FIG.
6.
[0053] A photodetection unit 94 for receiving the laser beam is
designed in belt-like shape extending vertically on both side
surfaces of the level sensor 7, and the photodetection unit 94 is
provided at a certain angle with respect to the front. The
photodetection unit 94 has photodetection elements serially
arranged in top-to-bottom direction. Based on the position of the
photodetection element which receives the light, it is possible to
judge at which position of the photodetection unit 94 the laser
beam 4 is received. On the rear surface, a groove 95 to engage with
the pole 6 is formed, and the level sensor 7 is mounted by engaging
the pole 6 into the groove 95.
[0054] The bulldozer 2 will be described.
[0055] The bulldozer 2 comprises the level sensor 7, an arithmetic
operation unit 104, a blade driving controller 109 for controlling
the position of the blade 5, and a radio transceiver unit 110.
[0056] First, description will be given on the blade driving
controller 109.
[0057] The level sensor 7 is mounted on the pole 6, and a distance
between a blade tip 5' of the blade 5 and reference position of the
level sensor 7 is a value already known. A detection signal of the
laser beam 4 by the level sensor 7 is inputted to an arithmetic
unit 96. At the arithmetic unit 96, height of the blade tip 5' is
calculated, and the arithmetic unit 96 issues a drive control
signal to an electric/hydraulic circuit 97. The electric/hydraulic
circuit 97 converts the electric signal to hydraulic pressure and
drives the hydraulic cylinder 98. The hydraulic cylinder 98 moves
the blade 5 up or down and determines its position. A display unit
99 is connected to the arithmetic unit 96, and the position of the
blade 5 or excavating status by the blade 5 is displayed on the
display unit 99.
[0058] Reference numeral 101 denotes an operation unit connected to
the arithmetic unit 96. Based on the display on the display unit
99, direct manual operation can be performed. An operator can
manually move the blade 5 up or down while watching the display on
the display unit 99 and can carry out the positioning operation. A
signal from the operation unit 101 is inputted to the arithmetic
unit 96. Based on the input signal, the arithmetic unit 96 drives
the hydraulic cylinder 98 via the electric/hydraulic circuit
97.
[0059] The arithmetic operation unit 104 is typically represented
by a personal computer, and it comprises an arithmetic unit 105 and
a storage unit 106. In the storage unit 106, topographical data
including the area for the scheduled construction, data such as
working data at the area of ground leveling operation, and an
arithmetic operation program are set and inputted. Based on the
above data, the arithmetic operation program calculates data which
the blade drive controller 109 requires for controlling. The
arithmetic operation unit 104 is particularly needed when
construction work is carried out along a predetermined route. In
this case, the direction of elevation is taken with the laser
reference plane as reference.
[0060] The working data as described above include the data such as
the level of the ground surface to be leveled, a tilt angle of the
leveled ground surface, a tilting direction of the leveled ground
surface, and further amounts of unevenness of the leveled ground
surface with respect to the reference plane.
[0061] Next, the radio transceiver unit 110 will be described.
[0062] The first GPS receiver 107 is provided at a place where
there is no obstacle to cut off or interrupt electric wave from a
satellite, e.g. a roof of the bulldozer 2. Information received by
the first GPS receiver 107 is inputted to the arithmetic unit 96.
The arithmetic unit 96 carries out arithmetic operation for
position surveying based on the signal from the first GPS receiver
107. The result of calculation is transmitted from a transmitter
108 to the radio transceiver 103. The transmitted data may be GPS
receiving data.
[0063] A construction operation system comprises, as described
above, the first GPS receiver 107 for detecting the position of the
bulldozer 2, the level sensor 7 for detecting the laser beam
reference plane, the arithmetic unit 96 for controlling the
position of the blade 5 based on the detection result of the level
sensor 7, the transmitter 108 for transmitting the results of
detection of the first GPS receiver 107 to the automatic surveying
system, etc. The construction operation of the bulldozer 2 is
controlled and operated by the construction operation system.
[0064] In the following, description will be given on
operation.
[0065] A plurality of the rotary laser irradiating systems 1a, 1b
and 1c are arranged in an area of the scheduled construction. At a
position away from the area of the scheduled construction and at a
known point, the automatic surveying system 10 and the second GPS
receiver 102 are arranged. Prior to the construction, the rotary
laser irradiating systems 1a, 1b and 1c and the automatic surveying
system 10 are arranged and adjusted so that these are at adequate
height.
[0066] By the operation control system 12, the automatic surveying
system 10 is operated. Distance (distance measurement) and position
(angle measurement) between the automatic surveying system 10 and
each of the rotary laser irradiating systems 1a, 1b and 1c are
measured.
[0067] That is, upon receipt of a command from the operation
control system 12, the control unit 24 of the automatic surveying
system 10 drives the light emitting unit 31 via the modulation
circuit 32 and irradiates the distance measuring light 30. Further,
the control unit 24 drives the horizontal motor 22 and the
elevation motor 23 via the rotary driving unit 25. By changing the
elevation angle, the distance measuring light 30 is projected
byrotary irradiation for scanning and searching the rotary
irradiating system main unit 35. The distance measuring light 30 is
reflected by the retroreflection prism 45 of the rotary irradiating
system main unit 35. When the reflection light is detected by the
photodetection unit 33, the distance is measured by the distance
measuring unit 29, and the horizontal angle and the elevation angle
are detected by the angle measuring unit 28. As a result, the
distance and the position between the automatic surveying system 10
and each of the rotary laser irradiating systems 1a, 1b and 1c are
measured.
[0068] Further, from the position of the automatic surveying system
10 and from the position of the bulldozer 2 surveyed using the
first GPS receiver 107, the operation control system 12 calculates
the relative positions of the bulldozer 2 and each of the rotary
laser irradiating systems 1a, 1b and 1c.
[0069] When surveying operation for the rotary laser irradiating
systems 1a, 1b and 1c has been completed, the arithmetic unit 13
calculates a machine height, a reference direction, tilting of the
reference plane, etc. of the rotary laser irradiating system 1 at
each position of the rotary laser irradiating systems 1a, 1b and 1c
from the surveying data (position data) of the rotary laser
irradiating systems 1a, 1b and 1c and from the working data stored
in the storage unit 14 so that the controlled blade tip 5' of the
bulldozer 2 is adjusted to an adequate height at that point.
[0070] The result of calculation of the arithmetic unit 13 is
inputted to the control unit 24. Based on the calculation results,
the control unit 24 drives the light emitting unit 31 via the
modulation circuit 32, and the calculation results are superimposed
on the distance measuring light 30 (or the tracing light 34) as
communication data. The transmission of the data is not limited to
the transmission via optical communication, but radio communication
may be used by providing the radio transceiver 103 with
transmitting function and by providing a radio receiver on the
rotary laser systems 1, and radio communication may be carried out
between the radio transceiver 103 and each of the rotary laser
irradiating systems 1. As the communication data to be transmitted
from the automatic surveying system 10 to the rotary irradiating
system main unit 35, there are data of the tilt angle and the
tilting direction necessary for forming a predetermined laser
reference plane by each of the rotary laser irradiating
systems.
[0071] In this case, the reflection light receiving unit 44 detects
the distance measuring light 30 from the automatic surveying system
10, and the rotary laser irradiating systems calculate direction in
which the rotary irradiating system main unit 35 is directed Based
on the result, the rotary irradiating system main unit 35 can be
directed in the direction designated by the automatic surveying
system 10.
[0072] To each of the rotary laser irradiating systems 1a, 1b and
1c, communication data is transmitted from the automatic surveying
system 10 via optical communication, for instance. The signal
received from the signal receiving unit 46 is inputted to the
control unit 72. The control unit 72 separates and extracts the
communication data superimposed on the distance measuring light 30.
Based on the communication data, the rotary irradiating system main
unit 35 is directed in the reference direction, and the rotary
laser irradiating systems are moved up or down to adjust to the
height designated by the operation control system 12. For instance,
if there are no surface irregularities in the area of the scheduled
construction, the height of each of the rotary laser irradiating
systems 1a, 1b and 1c from ground surface will be the same. If
there are much unevenness, the height will be different. The range
of the area where the bulldozer is operated under the control of
each rotary laser irradiating system is basically different.
[0073] The communication data to be superimposed on the distance
measuring light 30 include a tilt angle of the reference plane with
respect to the reference direction, and the control unit 72
operates the tilt setting unit 42. The tilt setting unit 42 drives
the tilting motor 62, tilts the light emitting unit 38 via the gear
train 63 and tilts the rotation shaft of the rotator 39 in a
predetermined direction at a predetermined angle.
[0074] When each of the rotary laser irradiating systems 1a, 1b and
1c has completed the operation, i.e. the operation to adjust the
machine height, to set the tilt angle of the reference plane, and
to set the reference direction, the light emitting unit 38 is
driven. The laser beam 4 is irradiated and is synchronously
rotated. By synchronous rotation, the laser beams 4 from the rotary
laser irradiating systems 1a, 1b and 1c do not enter the level
sensor 7 at the same time. By detecting the timing of the
photodetection or the receiving of the light from the level sensor
7 by the arithmetic unit 96, the timing of the receiving of the
light can be discriminated, and it is possible to judge and
identify reference planes 11a, 11b, and 11c formed by the rotary
laser irradiating systems 1a, 1b and 1c on the bulldozer 2.
[0075] It may be designed in such manner that, by separately
modulating the laser beams 4 irradiated by each of the rotary laser
irradiating systems 1a, 1b and 1c and by discriminating aspect of
modulation from the photodetection signal at the arithmetic unit
96, it is identified from which of the rotary laser irradiating
systems 1a, 1b or 1c the laser beam is irradiated, and the
reference planes 11a, 11b and 11c are identified.
[0076] By the rotary laser irradiating systems 1a, 1b and 1c, it is
possible to form the reference plane as desired for controlling the
operation of the bulldozer 2 in the total area of the scheduled
construction. Further, it is possible to form a reference plane for
construction work at the position of the bulldozer 2.
[0077] When the reference plane is formed, positioning of the blade
5 of the bulldozer 2 is carried out. The operation control system
12 selects one of the rotary laser irradiating systems 1a, 1b and
1c depending on the position of the bulldozer 2 and controls the
bulldozer 2. The bulldozer 2 selects a rotary laser irradiating
system to receive the light beam based on the communication from
the operation control system 12. Each of the laser beams projected
from the rotary laser irradiating systems is modulated.
[0078] Based on the photodetection signal from the level sensor 7,
the arithmetic unit 96 calculates the photo-receiving position on
the level sensor 7. The photo-receiving position and the reference
position are compared and calculated, and if there is a deviation,
a driving control signal is issued to the electric/hydraulic
circuit 97 so that the deviation will be corrected. The
electric/hydraulic circuit 97 drives the hydraulic cylinder 98 and
moves the blade 5 up or down. The level sensor 7 is moved up or
down integrally with the blade 5. Upward or downward movement of
the blade 5 is consistent with the upward or downward movement of
the level sensor 7. When the photo-receiving position of the level
sensor 7 is aligned with the reference position, the position of
the blade 5 is determined.
[0079] As described above, the topographical data and the working
data are set and inputted in the storage unit 106, and it is
possible to correct the level with respect to the reference plane
or to correct in order to tilt the leveled ground in a certain
direction with respect to the reference plane.
[0080] The bulldozer 2 is moved, and ground leveling operation is
performed. When the bulldozer 2 is moved, the photo-receiving
position on the level sensor 7 is varied. If the position of the
blade 5 is controlled via the electric/hydraulic circuit 97 in such
manner that the photo-receiving position will be the reference
position, it is possible to perform ground leveling operation over
the total area of the scheduled construction in accordance with the
working data.
[0081] When ground leveling operation is performed for the ground
with some surface irregularities with respect to the reference
plane, there are two types of control: blade level control by the
arithmetic operation unit 104 on the bulldozer 2, and blade level
control by the automatic surveying system 10.
[0082] First, description will be given on the blade level control
by the arithmetic operation unit 104. In this case, it is assumed
that the reference plane formed by each of the rotary laser
irradiating systems 1a, 1b and 1c is fixed so far as it is within
the photodetection range on the level sensor 7.
[0083] As described above, the arithmetic operation unit 104 is
provided with the topographical data and the working data. Thus, by
using the photo-receiving position as the reference and further by
correcting in view of the unevenness, and the position of the blade
5 can be calculated. By inputting the results of the calculation to
the arithmetic unit 96, the amount of this correction is taken into
account in the arithmetic unit 96, and the level control of the
blade 5 can be carried out via the electric/hydraulic circuit
97.
[0084] Next, description will be given on the blade level control
by the automatic surveying system 10. The arithmetic operation unit
104 does not correct the height direction of the photo-receiving
position on the level sensor 7, and it performs level control of
the blade 5 using only the reference plane as the reference. The
correction of the surface irregularities on the leveled ground is
performed by changing the reference plane formed by each of the
rotary laser irradiating systems 1a, 1b and 1c.
[0085] Because the operation control system 12 is provided with the
topographical data and the working data, the level of the ground
can be calculated at the point where the bulldozer 2 is operated.
Further, the data of the relative positions between the bulldozer 2
and each of the rotary laser irradiating systema 1a, 1b and 1c are
obtained by the calculation, and it is possible to calculate the
tilting direction and the tilt angle of the reference planes 11a,
11b and 11c in such manner that the photo-receiving position on the
level sensor 7 of each of the reference planes 11a, 11b and 11c,
which are formed by the rotary laser irradiating systems 1a, 1b and
1c, will be the position where construction work should be
performed.
[0086] The tilting direction and the tilt angle of each of the
reference planes are transmitted to the rotary laser irradiating
systems 1a, 1b, and 1c from the radio transceiver 103. Based on the
transmitted data, each of the rotary laser irradiating systems 1a,
1b and 1c tilts the reference plane in a predetermined direction at
a predetermined angle. When the working site of the bulldozer 2 is
moved, the data of the reference planes to be formed are
correspondingly transmitted from the automatic surveying system 10
to each of the rotary laser irradiating systems 1a, 1b and 1c, and
the height and the tilt angle of the reference planes can be
changed by each of the rotary laser irradiating systems 1a, 1b and
1c, and a ground surface with convex and concave as desired can be
prepared.
[0087] FIG. 7 shows a case where the construction equipment is a
grader 111.
[0088] The grader 111 is provided with hydraulic cylinders 113a and
113b, which are independently driven and operated and mounted at
left side and right side of a blade 112 respectively.
[0089] When the hydraulic cylinders 113a and 113b are controlled
independently on the grader 111, the blade 112 can be tilted, and
it is possible to form a prepared surface which is curved convexly
such as a road.
[0090] The height adjustment of the blade 5 and the blade 112 can
be controlled manually by a ground leveling operator on the
bulldozer 2 or the grader 111 via the electric/hydraulic circuit 97
from the operation unit 101 based on the photodetection status on
the level sensor displayed on the display unit 99.
[0091] Further, the level sensor 7 is provided on the blade 5 in
the above embodiment, while the level sensor 7 may be provided on a
vehicle body of the bulldozer 2. This is accomplished when it is
designed in such manner that the position of the blade tip 5' is
detected via extending or shrinking status of the hydraulic
cylinder 98 or via a position of an arm which supports the blade
5.
[0092] According to the present invention, a reference plane can be
set by a plurality of rotary laser irradiating systems. As a
result, the laser reference plane can be formed for wider area, and
this eliminates the procedure of re-setting operation of the
reference plane on the same construction area. Also, even at a
construction site where there is an obstacle to cut off the laser
beam, construction work can be performed without re-setting. This
makes it possible to eliminate troublesome procedure to stop the
working each time for re-setting during construction work. As a
result, working efficiency is improved, and error due to the
re-setting can be avoided.
* * * * *