Patent Publication Number: US-2021164192-A1

Title: Loading machine control device and control method

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a U.S. National stage application of International Application No. PCT/JP2019/033685, filed on Aug. 28, 2019. This U.S. National stage application claims priority under 35 U.S.C. § 119(a) to Japanese Patent Application No. 2018-170738, filed in Japan on Sep. 12, 2018, the entire contents of which are hereby incorporated herein by reference. 
    
    
     BACKGROUND 
     Field of the Invention 
     The present invention relates to a control device and a control method for a loading machine. 
     Background Information 
     Japanese Unexamined Patent Application, First Publication No. H09-256407 discloses a technique relating to automatic loading control of a loading machine. In the automatic loading control, a control device receives a specified loading point from an operator or the like of the loading machine, and the control device controls the motion of the loading machine and work equipment to cause a bucket to move to the loading point. According to the technique described in Japanese Unexamined Patent Application, First Publication No. H09-256407, the control device stores a time series of the positions of the work equipment in advance to cause the work equipment to be operated according to the time series. 
     SUMMARY 
     According to the technique described in Japanese Unexamined Patent Application, First Publication No. H09-256407, the work equipment automatically moves to the loading point stored in advance, and earth is dumped at the loading point. There is a demand that the work equipment automatically moves to an excavation point after the earth is dumped at the loading point. At this time, the work equipment is required to move such that the bucket does not interfere with a loading target. 
     An object of the present invention is to provide a control device and a control method for a loading machine, which can cause a bucket to move to an excavation point such that a loading target and the bucket do not interfere with each other. 
     According to a first aspect of the present invention, a control device of a loading machine is provided including a swing body that swings around a center of swing and work equipment that includes a bucket and is attached to the swing body, the device including: a loading target specifying unit that specifies a position and shape of a loading target; an avoidance position specifying unit that specifies an interference avoidance position which is located outward from the loading target by a predetermined distance, based on the position and shape of the loading target; and a movement processing unit that outputs an operation signal to drive only the swing body until the bucket reaches the interference avoidance position from a loading position above the loading target, to cause the bucket to move to the interference avoidance position, and outputs an operation signal to drive the swing body and the work equipment after the bucket has reached the interference avoidance position, to cause the bucket to move to an excavation position above an excavation target. 
     According to at least one of the above aspects, the control device of the loading machine can cause the bucket to move to an excavation point while preventing interference between the loading target and the bucket. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a schematic view illustrating a configuration of a loading machine according to a first embodiment. 
         FIG. 2  is a schematic block diagram illustrating a configuration of a control device according to the first embodiment. 
         FIG. 3  is a view illustrating an example of the path of a bucket before excavation in automatic excavation and loading control according to the first embodiment. 
         FIG. 4  is a view illustrating an example of the path of the bucket after excavation in the automatic excavation and loading control according to the first embodiment. 
         FIG. 5  is a flowchart illustrating the automatic excavation and loading control according to the first embodiment. 
         FIG. 6  is a flowchart illustrating the automatic excavation and loading control according to the first embodiment. 
         FIG. 7  is a flowchart illustrating the automatic excavation and loading control according to the first embodiment. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENT(S) 
     Hereinafter, an embodiment will be described in detail with reference to the drawings. 
     First Embodiment 
     (Configuration of Loading Machine) 
       FIG. 1  is a schematic view illustrating a configuration of a loading machine according to a first embodiment. 
     A loading machine  100  is a work machine that loads earth to a loading point such as a transport vehicle. The loading machine  100  according to the first embodiment is a hydraulic excavator. Incidentally, the loading machine  100  according to another embodiment may be a loading machine other than the hydraulic excavator. In addition, the loading machine  100  illustrated in  FIG. 1  is a backhoe excavator, but may be a face excavator or a rope excavator. 
     The loading machine  100  includes an undercarriage  110 , a swing body  120  supported by the undercarriage  110 , and work equipment  130  that is driven by hydraulic pressure and is supported by the swing body  120 . The swing body  120  is supported so as to be swingable around the center of swing. 
     The work equipment  130  includes a boom  131 , an arm  132 , a bucket  133 , a boom cylinder  134 , an arm cylinder  135 , a bucket cylinder  136 , a boom stroke sensor  137 , an arm stroke sensor  138 , and a bucket stroke sensor  139 . 
     A proximal end portion of the boom  131  is attached to the swing body  120  via a pin. 
     The arm  132  connects the boom  131  and the bucket  133 . A proximal end portion of the arm  132  is attached to a tip end portion of the boom  131  via a pin. 
     The bucket  133  includes a blade that excavates earth or the like and a container that carries the excavated earth. A proximal end portion of the bucket  133  is attached to a tip end portion of the arm  132  via a pin. 
     The boom cylinder  134  is a hydraulic cylinder that operates the boom  131 . A proximal end portion of the boom cylinder  134  is attached to the swing body  120 . A tip end portion of the boom cylinder  134  is attached to the boom  131 . 
     The arm cylinder  135  is a hydraulic cylinder that drives the arm  132 . A proximal end portion of the arm cylinder  135  is attached to the boom  131 . A tip end portion of the arm cylinder  135  is attached to the arm  132 . 
     The bucket cylinder  136  is a hydraulic cylinder that drives the bucket  133 . A proximal end portion of the bucket cylinder  136  is attached to the arm  132 . A tip end portion of the bucket cylinder  136  is attached to a link mechanism that rotates the bucket  133 . 
     The boom stroke sensor  137  measures the stroke amount of the boom cylinder  134 . The stroke amount of the boom cylinder  134  can be converted into the inclination angle of the boom  131  with respect to the swing body  120 . Hereinafter, the inclination angle with respect to the swing body  120  is also referred to as an absolute angle. Namely, the stroke amount of the boom cylinder  134  can be converted into the absolute angle of the boom  131 . 
     The arm stroke sensor  138  measures the stroke amount of the arm cylinder  135 . The stroke amount of the arm cylinder  135  can be converted into the inclination angle of the arm  132  with respect to the boom  131 . Hereinafter, the inclination angle of the arm  132  with respect to the boom  131  is also referred to as a relative angle of the arm  132 . 
     The bucket stroke sensor  139  measures the stroke amount of the bucket cylinder  136 . The stroke amount of the bucket cylinder  136  can be converted into the inclination angle of the bucket  133  with respect to the arm  132 . Hereinafter, the inclination angle of the bucket  133  with respect to the arm  132  is also referred to as a relative angle of the bucket  133 . 
     Incidentally, the loading machine  100  according to another embodiment may include angle sensors that detect an inclination angle with respect to the ground surface or an inclination angle with respect to the swing body  120 , instead of the boom stroke sensor  137 , the arm stroke sensor  138 , and the bucket stroke sensor  139 . 
     The swing body  120  is provided with a cab  121 . An operator seat  122  in which an operator sits, an operation device  123  that operates the loading machine  100 , and a detection device  124  that detects the three-dimensional position of an object existing in a detection direction are provided inside the cab  121 . The operation device  123  generates a raising operation signal and a lowering operation signal for the boom  131 , a push operation signal and a pull operation signal for the arm  132 , a dump operation signal and an excavation operation signal for the bucket  133 , and rightward and leftward swing operation signals for the swing body  120  in response to an operation of the operator, to output the generated signals to a control device  128 . In addition, the operation device  123  generates an excavation and loading instruction signal to cause the work equipment  130  to start automatic excavation and loading control in response to an operation of the operator and outputs the generated excavation and loading instruction signal to the control device  128 . The automatic excavation and loading control is control that causes automatic execution of a series of motions including the swing of the swing body  120  to move the work equipment  130  to an excavation point, the excavation of earth at the excavation point, and the swing of the swing body  120  to load the earth, which is contained in the bucket  133 , into a loading target  200  (for example, a transport vehicle or a hopper). 
     The operation device  123  includes, for example, a lever, a switch and a pedal. The excavation and loading instruction signal is generated by operating a switch for automatic control. For example, when the switch is turned on, the excavation and loading instruction signal is output. The operation device  123  is disposed in the vicinity of the operator seat  122 . The operation device  123  is located within a range where the operator can operate the operation device  123  when the operator sits in the operator seat  122 . 
     Examples of the detection device  124  include a stereo camera, a LiDAR device, a laser scanner, and the like. The detection device  124  is provided, for example, such that the detection direction thereof faces the front of the cab  121  of the loading machine  100 . The detection device  124  specifies the three-dimensional position of an object in a coordinate system with respect to the position of the detection device  124 . 
     Incidentally, the loading machine  100  according to the first embodiment takes a motion according to an operation of the operator sitting in the operator seat  122 ; however, the present invention is not limited thereto in another embodiment. For example, the loading machine  100  according to another embodiment may take a motion by receiving an operation signal or an excavation and loading instruction signal transmitted by a remote operation of the operator performing operation outside the loading machine  100 . 
     The loading machine  100  includes a position and azimuth direction calculator  125 , an inclination measurement instrument  126 , a hydraulic device  127 , and the control device  128 . 
     The position and azimuth direction calculator  125  calculates the position of the swing body  120  and the azimuth direction of the swing body  120 . The position and azimuth direction calculator  125  includes two receivers that receive positioning signals from artificial satellites forming the GNSS. The two receivers are installed at different positions on the swing body  120 . The position and azimuth direction calculator  125  detects the position of a representative point of the swing body  120  in a site coordinate system (origin of an excavator coordinate system) based on the positioning signals received by the receivers. 
     The position and azimuth direction calculator  125  uses the positioning signals, which are received by the two receivers, to calculate the azimuth direction of the swing body  120  as a relationship between the installation position of one receiver and the installation position of the other receiver. The azimuth direction of the swing body  120  is the front direction of the swing body  120  and is equal to a horizontal component of the extending direction of a straight line extending from the boom  131  to the bucket  133  of the work equipment  130 . 
     The inclination measurement instrument  126  measures the acceleration and angular speed of the swing body  120  to detect the posture (for example, the roll angle and the pitch angle) of the swing body  120  based on a measurement result. The inclination measurement instrument  126  is installed, for example, on a lower surface of the swing body  120 . For example, an inertial measurement unit (IMU) can be used as the inclination measurement instrument  126 . 
     The hydraulic device  127  includes a hydraulic oil tank, a hydraulic pump, and a flow rate control valve. The hydraulic pump is driven by power of an engine (unillustrated) to supply a hydraulic oil to a travel hydraulic motor (unillustrated) that causes the undercarriage  110  to travel, a swing hydraulic motor (unillustrated) that swings the swing body  120 , the boom cylinder  134 , the arm cylinder  135 , and the bucket cylinder  136  via the flow rate control valve. The flow rate control valve includes a spool having a rod shape, and adjusts the flow rate of the hydraulic oil to be supplied to the travel hydraulic motor, the swing hydraulic motor, the boom cylinder  134 , the arm cylinder  135 , and the bucket cylinder  136 . The spool is driven according to a control command received from the control device  128 . Namely, the amount of the hydraulic oil to be supplied to the travel hydraulic motor, the swing hydraulic motor, the boom cylinder  134 , the arm cylinder  135 , and the bucket cylinder  136  is controlled by the control device  128 . As described above, the boom cylinder  134 , the arm cylinder  135 , and the bucket cylinder  136  are driven by the hydraulic oil supplied from the hydraulic device  127  that is common. 
     The control device  128  receives an operation signal from the operation device  123 . The control device  128  drives the work equipment  130 , the swing body  120 , or the undercarriage  110  according to the received operation signal. 
     (Configuration of Control Device) 
       FIG. 2  is a schematic block diagram illustrating a configuration of the control device according to the first embodiment. 
     The control device  128  is a computer including a processor  1100 , a main memory  1200 , a storage  1300 , and an interface  1400 . The storage  1300  stores a program. The processor  1100  reads the program from the storage  1300  to deploy the program in the main memory  1200  and to then execute a process according to the program. 
     Examples of the storage  1300  include a HDD, a SSD, a magnetic disk, a magneto-optical disk, a CD-ROM, a DVD-ROM and the like. The storage  1300  may be an internal medium directly connected to a common communication line of the control device  128 , or may be an external medium connected to the control device  128  via the interface  1400 . The storage  1300  is a non-transitory type storage medium. 
     The processor  1100  executes the program and includes a vehicle information acquisition unit  1101 , a detection information acquisition unit  1102 , an operation signal input unit  1103 , a bucket position specifying unit  1104 , a map generation unit  1105 , a loading target specifying unit  1106 , an avoidance position specifying unit  1107 , an excavation target specifying unit  1108 , an excavation position specifying unit  1109 , a lowering stop determination unit  1110 , a loading position specifying unit  1111 , a movement processing unit  1112 , and an operation signal output unit  1113 . 
     The vehicle information acquisition unit  1101  acquires, for example, the swing speed, position, and azimuth direction of the swing body  120 , the inclination angles of the boom  131 , the arm  132 , and the bucket  133 , and the posture of the swing body  120 . Hereinafter, information regarding the loading machine  100  acquired by the vehicle information acquisition unit  1101  is referred to as vehicle information. 
     The detection information acquisition unit  1102  acquires depth information from the detection device  124 . The depth information indicates the three-dimensional positions of a plurality of points within a detection range R. Examples of the depth information include a depth image formed of a plurality of pixels representing depths, and point cloud data formed of a plurality of points represented by a Cartesian coordinate system (x, y, z). 
     The operation signal input unit  1103  receives an input of an operation signal from the operation device  123 . The operation signal includes a raising operation signal and a lowering operation signal for the boom  131 , a push operation signal and a pull operation signal for the arm  132 , a dump operation signal and an excavation operation signal for the bucket  133 , a swing operation signal for the swing body  120 , a travel operation signal for the undercarriage  110 , and an excavation and loading instruction signal for the loading machine  100 . 
       FIG. 3  is a view illustrating an example of the path of the bucket before excavation in the automatic excavation and loading control according to the first embodiment. 
     The bucket position specifying unit  1104  specifies a position P (refer to  FIG. 1 ) of the tip end portion of the arm  132  in the excavator coordinate system and a height Hb from a tip end of the arm  132  to the lowest passing point of the bucket  133  based on the vehicle information acquired by the vehicle information acquisition unit  1101 . The lowest passing point of the bucket  133  refers to a point where the teeth is located when the distance between the teeth and the ground surface during a dump operation of the bucket  133  is the shortest. Namely, the height Hb from the tip end of the arm  132  to the lowest passing point of the bucket  133  coincides with the length from the pin of the proximal end portion of the bucket  133  to the teeth. Incidentally, since the proximal end portion of the bucket  133  is connected to the tip end portion of the arm  132 , the position P of the tip end portion of the arm  132  is equal to the position of the proximal end portion of the bucket  133 . 
     Specifically, the bucket position specifying unit  1104  specifies the position P of the tip end portion of the arm  132  according to the following procedure. The bucket position specifying unit  1104  obtains the position of the tip end portion of the boom  131  based on the absolute angle of the boom  131  obtained from the stroke amount of the boom cylinder  134  and the known length of the boom  131  (distance from the pin of the proximal end portion to the pin of the tip end portion). The bucket position specifying unit  1104  obtains the absolute angle of the arm  132  based on the absolute angle of the boom  131  and the relative angle of the arm  132  obtained from the stroke amount of the arm cylinder  135 . The bucket position specifying unit  1104  obtains the position P of the tip end portion of the arm  132  based on the position of the tip end portion of the boom  131 , the absolute angle of the arm  132 , and the known length of the arm  132  (distance from the pin of the proximal end portion to the pin of the tip end portion). 
     The map generation unit  1105  generates a three-dimensional map representing the shape of at least a portion around the loading machine  100  in the site coordinate system, based on the position, azimuth direction, and posture of the swing body  120  acquired by the vehicle information acquisition unit  1101  and the depth information acquired by the detection information acquisition unit  1102 . The map generation unit  1105  superimposes a plurality of depth information, which is detected for different detection ranges by the detection device  124  when the swing body  120  swings, to generate a three-dimensional map including the loading target  200  and an excavation target. Incidentally, in another embodiment, the map generation unit  1105  may generate a three-dimensional map in the excavator coordinate system with respect to the swing body  120 . 
     The loading target specifying unit  1106  specifies the position and shape of the loading target  200  based on the three-dimensional map generated by the map generation unit  1105 . For example, the loading target specifying unit  1106  matches a three-dimensional shape illustrated by the three-dimensional map to the known shape of the loading target  200  to specify the position and shape of the loading target  200 . 
     The avoidance position specifying unit  1107  specifies an interference avoidance position P 02  which is a point where the work equipment  130  and the loading target  200  do not interfere with each other in a plan view from above, based on the position of the loading machine  100  acquired by the vehicle information acquisition unit  1101  and the position and shape of the loading target  200  specified by the loading target specifying unit  1106 . The interference avoidance position P 02  is a position which has the same height as the position P (no-load swing start position P 01 ) of the tip end of the arm  132  at the start of the automatic excavation and loading control, to which the distance from the center of swing of the swing body  120  is equal to the distance from the center of swing to the no-load swing start position P 01 , and below which the loading target  200  does not exist. For example, the avoidance position specifying unit  1107  specifies a circle having the center of swing of the swing body  120  as a center and having the distance between the center of swing and the no-load swing start position P 01  as a radius, to specify a position, at which the outer shape of the bucket  133  does not interfere with the loading target  200  in a plan view from above and which is the closest to the no-load swing start position P 01 , among positions on the circle as the interference avoidance position P 02 . The avoidance position specifying unit  1107  can determine whether or not the loading target  200  and the bucket  133  interfere with each other, based on the position and shape of the loading target  200  and the known shape of the bucket  133 . Here, “the same height” and “equal distance” are not necessarily limited to a case where the heights or the distances completely coincide with each other and allow some errors and margins. 
     The excavation target specifying unit  1108  specifies the position of an excavation point P 22  of the excavation target based on the three-dimensional map generated by the map generation unit  1105 . The excavation point P 22  is, for example, a point from the teeth of the bucket  133  are moved in an excavation direction of the arm  132  and the bucket  133 , so that the amount of earth corresponding to the maximum capacity of the bucket  133  can be excavated at the point. For example, the excavation target specifying unit  1108  specifies the distribution of earth of the excavation target from the three-dimensional shape illustrated by the three-dimensional map and specifies the excavation point P 22  based on the distribution. 
     The excavation position specifying unit  1109  specifies a point which is apart from the excavation point P 22  specified by the excavation target specifying unit  1108  by the distance from the proximal end portion to the teeth of the bucket  133 , as an excavation position P 05 . Namely, in a case where the bucket  133  takes a predetermined excavation posture where the teeth faces a dump direction, when the teeth of the bucket  133  is located at the excavation point P 22 , the tip end of the arm  132  is located at the excavation position P 05 . Since the excavation point P 22  is specified based on the three-dimensional map, it can be said that the excavation position specifying unit  1109  specifies the excavation position P 05  based on the detection result of the detection device  124 . Incidentally, in another embodiment, the excavation position specifying unit  1109  may specify the excavation position P 05  according to an instruction of the operator of the loading machine  100 . For example, the operator may put the bucket  133  at the excavation position P 05  to press a predetermined button and to thus instruct the excavation position P 05 , or may use an input device such as a touch panel to instruct the excavation position P 05 . 
     In addition, the excavation position specifying unit  1109  determines a position, which is located above the excavation position P 05  by a predetermined height, as a swing end position P 04 . 
     The lowering stop determination unit  1110  determines whether or not the height of the tip end of the arm  132  is the same height as the swing end position P 04  when the lowering operation of the work equipment  130  is performed at the same time no-load swing of the swing body  120  is performed. The position of the tip end of the arm  132  at this time is referred to as a lowering stop position P 03 . 
     The loading position specifying unit  1111  specifies a loading position P 07  based on the position and shape of the loading target  200  specified by the loading target specifying unit  1106 . Specifically, the loading position specifying unit  1111  specifies the loading position P 07  as follows. 
       FIG. 4  is a view illustrating an example of the path of the bucket after excavation in the automatic excavation and loading control according to the first embodiment. 
     The loading position specifying unit  1111  specifies a loading point P 21  above the loading target  200  as the plane position of the loading position P 07 . Namely, when the tip end of the arm  132  is located at the loading position P 07 , the tip end of the arm  132  is located above the loading point P 21 . Examples of the loading point P 21  include the center point of a vessel when the loading target  200  is a dump truck, and the center point of an opening when the loading target  200  is a hopper. The loading position specifying unit  1111  adds the height Hb from the tip end of the arm  132  to the lowest passing point of the bucket  133 , the height Hb being specified by the bucket position specifying unit  1104 , and the height of a control margin of the bucket  133  to a height Ht of the loading target  200  to specify the height of the loading position P 07 . Incidentally, in another embodiment, the loading position specifying unit  1111  may specify the loading position P 07  without adding the height of the control margin. Namely, the loading position specifying unit  1111  may add the height Hb to the height Ht to specify the height of the loading position P 07 . Incidentally, the height Ht according to the first embodiment is a height from the ground to an upper surface of the vessel. 
     When the operation signal input unit  1103  receives an input of the excavation and loading instruction signal, the movement processing unit  1112  generates a rotation operation signal to cause the bucket  133  to move to the excavation position P 05 , based on the excavation position P 05  specified by the excavation position specifying unit  1109  and the interference avoidance position P 02  specified by the avoidance position specifying unit  1107 . Namely, the movement processing unit  1112  generates a rotation operation signal such that the bucket  133  reaches the excavation position P 05  from the no-load swing start position P 01  via the interference avoidance position P 02 , the lowering stop position P 03 , and the swing end position P 04 . When the bucket  133  reaches the excavation position P 05 , the movement processing unit  1112  generates an excavation operation signal to cause the bucket  133  to rotate or move in the excavation direction. 
     The movement processing unit  1112  generates a rotation operation signal to cause the bucket  133  to move to the loading position P 07  based on the loading position P 07  specified by the loading position specifying unit  1111  and the interference avoidance position P 02  specified by the avoidance position specifying unit  1107 . Namely, the movement processing unit  1112  generates a rotation operation signal to cause the bucket  133  to reach the loading position P 07  from an excavation completion position P 05 ′ via a load swing start position P 06  and the interference avoidance position P 02 . At this time, the movement processing unit  1112  generates the rotation operation signal for the bucket  133  such that the ground angle of the bucket  133  is not changed even when the boom  131  and the arm  132  are driven. When the bucket  133  reaches the loading position P 07 , the movement processing unit  1112  generates a dump operation signal to cause the bucket  133  to rotate in the dump direction. 
     The operation signal output unit  1113  outputs the operation signal input to the operation signal input unit  1103  or the operation signal generated by the movement processing unit  1112 . Specifically, the operation signal output unit  1113  outputs the operation signal related to automatic control generated by the movement processing unit  1112  when the automatic excavation and loading control is in progress and outputs the operation signal related to a manual operation of the operator input to the operation signal input unit  1103  when the automatic excavation and loading control is not in progress. 
     (Automatic Excavation and Loading Control) 
     When the operator of the loading machine  100  determines that the loading machine  100  and the loading target  200  are in a positional relationship where a loading process can be performed, the operator turns on the switch for automatic control of the operation device  123 . Accordingly, the operation device  123  generates and outputs the excavation and loading instruction signal. 
       FIGS. 5 and 7  are flowcharts illustrating the automatic excavation and loading control according to the first embodiment. When the control device  128  receives an input of the excavation and loading instruction signal from the operator, the control device  128  executes the automatic excavation and loading control illustrated in  FIGS. 5 to 7 . Incidentally, the no-load swing start position P 01 , which is the position of the bucket  133  at the start of the automatic excavation, is a position above the loading target  200  and the position does not interfere with the loading target  200  during swing. When the automatic excavation and loading control is continuously executed, the no-load swing start position P 01  coincides with the loading position P 07 . 
     The vehicle information acquisition unit  1101  acquires the position and azimuth direction of the swing body  120 , the inclination angles of the boom  131 , the arm  132 , and the bucket  133 , and the posture of the swing body  120  (step S 1 ). The vehicle information acquisition unit  1101  specifies the position of the center of swing of the swing body  120  based on the acquired position and azimuth direction of the swing body  120  (step S 2 ). 
     The detection information acquisition unit  1102  acquires the depth information indicating depths around the loading machine  100  from the detection device  124  (step S 3 ). The map generation unit  1105  updates the three-dimensional map representing the shape of at least a portion around the loading machine  100  in the site coordinate system, based on the position, azimuth direction, and posture of the swing body  120  acquired by the vehicle information acquisition unit  1101  and the depth information acquired by the detection information acquisition unit  1102  (step S 4 ). Namely, the map generation unit  1105  superimposes the depth information detected this time on the three-dimensional map generated in the past to update the three-dimensional map. The loading target specifying unit  1106  specifies the position and shape of the loading target  200  based on the updated map information (step S 5 ). 
     The bucket position specifying unit  1104  determines the position P of the tip end portion of the arm  132  when the excavation and loading instruction signal is input as the no-load swing start position P 01  and specifies the height Hb from the tip end of the arm  132  to the lowest passing point of the bucket  133 , based on the vehicle information acquired by the vehicle information acquisition unit  1101  (step S 6 ). 
     The excavation target specifying unit  1108  specifies the excavation point P 22  based on the three-dimensional map generated in step S 4  (step S 7 ). The excavation position specifying unit  1109  specifies the excavation position P 05  and the swing end position P 04  based on the position of the excavation point P 22  specified by the excavation target specifying unit  1108  (step S 8 ). 
     The avoidance position specifying unit  1107  specifies the interference avoidance position P 02  based on the no-load swing start position P 01  determined in step S 6  and the position and shape of the loading target  200  specified by the loading target specifying unit  1106  (step S 9 ). 
     The movement processing unit  1112  determines whether or not the position P of the tip end portion of the arm  132  has reached the swing end position P 04  (step S 10 ). When the position P of the tip end portion of the arm  132  has not reached the swing end position P 04  (step S 10 : NO), the movement processing unit  1112  determines whether or not the position P of the tip end portion of the arm  132  has passed through the interference avoidance position P 02  (step S 11 ). When the position P of the tip end portion of the arm  132  has not passed through the interference avoidance position P 02  (step S 11 : NO), the movement processing unit  1112  does not generate an operation signal for the boom  131 , the arm  132 , and the bucket  133 . Namely, when the position P of the tip end portion of the arm  132  has not passed through the interference avoidance position P 02 , the movement processing unit  1112  prohibits the output of an operation signal that causes the work equipment  130  to be lowered. 
     On the other hand, when the position P of the tip end portion of the arm  132  has passed through the interference avoidance position P 02  (step S 11 : YES), the lowering stop determination unit  1110  determines whether or not the position P of the tip end of the arm  132  is higher than the swing end position P 04  (step S 12 ). When the position P of the tip end of the arm  132  is higher than the swing end position P 04  (step S 12 : YES), the movement processing unit  1112  generates an operation signal for the boom  131  and the arm  132  to cause the position P of the tip end portion of the arm  132  to be lowered (step S 13 ). 
     On the other hand, when the height of the position P of the tip end of the arm  132  is the height of the swing end position P 04  or less (step S 13 : NO), the movement processing unit  1112  temporarily stops generating an operation signal for the boom  131  and the arm  132  which causes the lowering of the position P of the tip end portion of the arm  132 . 
     Next, the movement processing unit  1112  determines whether or not the plane position of the tip end of the arm  132  will reach the swing end position P 04  when the output of the swing operation signal is stopped from the current time (step S 14 ). In a case where the plane position of the tip end of the arm  132  will not reach the swing end position P 04  when the output of the swing operation signal is stopped from the current time (step S 14 : NO), the movement processing unit  1112  generates the swing operation signal (step S 15 ). 
     On the other hand, in a case where the plane position of the tip end of the arm  132  will reach the swing end position P 04  when the output of the swing operation signal is stopped from the current time (step S 14 : YES), the movement processing unit  1112  does not generate the swing operation signal. Namely, in the case where the plane position of the tip end of the arm  132  reaches the swing end position P 04  when the output of the swing operation signal is stopped from the current time, the movement processing unit  1112  prohibits the output of the swing operation signal. Accordingly, the swing body  120  which continues to swing due to inertia starts decelerating. 
     When at least one of the operation signals for the boom  131  and the arm  132  and the swing operation signal for the swing body  120  is generated in the process from step S 10  to step S 15 , the operation signal output unit  1113  outputs the generated operation signal to the hydraulic device  127  (step S 16 ). 
     Then, the vehicle information acquisition unit  1101  acquires the vehicle information (step S 17 ). Accordingly, the vehicle information acquisition unit  1101  can acquire vehicle information after driving by the output operation signal. The control device  128  causes the process to return to step S 14  to repeatedly execute the generation of an operation signal. 
     In step S 10 , when the position P of the tip end portion of the arm  132  has reached the swing end position P 04  (step S 10 : YES), the movement processing unit  1112  generates an operation signal to cause the boom  131  and the arm  132  to be lowered, and the operation signal output unit  1113  outputs the generated operation signal to the hydraulic device  127  (step S 18 ). The vehicle information acquisition unit  1101  acquires the vehicle information to determine whether or not the position P of the tip end portion of the arm  132  has reached the excavation position P 05  (step S 19 ). When the position P of the tip end portion of the arm  132  has not reached the excavation position P 05  (step S 19 : NO), the control device  128  causes the process to return to step S 22  to continue to output an operation signal that causes the work equipment  130  to be lowered. Therefore, the swing body  120  does not swing while the position P of the tip end portion of the arm  132  is moved from the swing end position P 04  to the excavation position P 05 . 
     When the position P of the tip end portion of the arm  132  has reached the excavation position P 05  (step S 19 : YES), the movement processing unit  1112  generates an excavation operation signal to cause the bucket  133  to be driven in the excavation direction, and the operation signal output unit  1113  outputs the generated operation signal to the hydraulic device  127  (step S 20 ). Accordingly, the control device  128  can cause the bucket  133  to excavate the excavation target. 
     Next, the vehicle information acquisition unit  1101  acquires vehicle information (step S 21 ). In addition, the detection information acquisition unit  1102  acquires depth information indicating depths around the loading machine  100  from the detection device  124  (step S 22 ). The map generation unit  1105  updates the three-dimensional map based on the vehicle information acquired by the vehicle information acquisition unit  1101  and the depth information acquired by the detection information acquisition unit  1102  (step S 23 ). The loading target specifying unit  1106  specifies the position and shape of the loading target  200  based on the updated three-dimensional map (step S 24 ). The loading position specifying unit  1111  specifies the plane position of the loading position P 07  based on the position and shape of the loading target  200  specified by the loading target specifying unit  1106  (step S 25 ). The loading position specifying unit  1111  adds the height Hb from the tip end portion of the arm  132  to the lowest passing point of the bucket  133  specified in step S 6  and the height of a control margin of the bucket  133  to the height Ht of the loading target  200  to specify the height of the loading position P 07  (step S 26 ). 
     The movement processing unit  1112  determines whether or not the position P of the tip end portion of the arm  132  has reached the loading position P 07  (step S 27 ). When the position P of the tip end portion of the arm  132  has not reached the loading position P 07  (step S 27 : NO), the movement processing unit  1112  determines whether or not the position P of the tip end portion of the arm  132  is in the vicinity of the interference avoidance position P 02  (step S 28 ). For example, the movement processing unit  1112  determines whether or not a difference between the height of the tip end of the arm  132  and the height of the interference avoidance position P 02  is less than a predetermined threshold value, or a difference between the plane distance from the center of swing of the swing body  120  to the tip end of the arm  132  and the plane distance from the center of swing to the interference avoidance position P 02  is less than a predetermined threshold value (step S 28 ). When the position P of the tip end portion of the arm  132  is not in the vicinity of the interference avoidance position P 02  (step S 28 : NO), the movement processing unit  1112  generates an operation signal to cause the boom  131  and the arm  132  to be raised to the height of the interference avoidance position P 02  (step S 29 ). At this time, the movement processing unit  1112  generates an operation signal based on the positions and speeds of the boom  131  and the arm  132 . 
     In addition, the movement processing unit  1112  calculates the sum of the angular speeds of the boom  131  and the arm  132  based on the generated operation signal for the boom  131  and the arm  132  and generates an operation signal to cause the bucket  133  to rotate at the same speed as the sum of the angular speeds (step S 30 ). Accordingly, the movement processing unit  1112  can generate an operation signal to cause the ground angle of the bucket  133  to be held. 
     When the position P of the tip end portion of the arm  132  is in the vicinity of the interference avoidance position P 02  (step S 28 : YES), the movement processing unit  1112  does not generate an operation signal for the boom  131 , the arm  132 , and the bucket  133 . Namely, when the position P of the tip end portion of the arm  132  is in the vicinity of the interference avoidance position P 02 , the movement processing unit  1112  prohibits the output of the operation signal for the work equipment  130  which causes the work equipment  130  to move to the loading point. 
     The movement processing unit  1112  determines whether or not the swing speed of the swing body  120  is less than a predetermined speed, based on the vehicle information acquired by the vehicle information acquisition unit  1101  (step S 31 ). Namely, the movement processing unit  1112  determines whether or not the swing of the swing body  120  is in progress. 
     When the swing speed of the swing body  120  is less than the predetermined speed (step S 31 : YES), the movement processing unit  1112  specifies a rise time which is the time taken for the height of the bucket  133  to reach the height of the interference avoidance position P 02  from the height of the excavation completion position P 05 ′ (step S 32 ). The movement processing unit  1112  determines whether or not the tip end of the arm  132  will pass through the interference avoidance position P 02  or a point higher than the interference avoidance position P 02  when the swing operation signal is output from the current time, based on the rise time of the bucket  133  (step S 33 ). In a case where the tip end of the arm  132  will pass through the interference avoidance position P 02  or the point higher than the interference avoidance position P 02  when the swing operation signal is output from the current time (step S 33 : YES), the movement processing unit  1112  generates the swing operation signal (step S 34 ). 
     In a case where the tip end of the arm  132  passes through a point lower than the interference avoidance position P 02  when the swing operation signal is output from the current time (step S 33 : NO), the movement processing unit  1112  does not generate the swing operation signal. Namely, when the tip end of the arm  132  passes through the point lower than the interference avoidance position P 02 , the movement processing unit  1112  prohibits the output of the swing operation signal. 
     When the swing speed of the swing body  120  is the predetermined speed or more (step S 31 : NO), the movement processing unit  1112  determines whether or not the tip end of the arm  132  will reach the loading position P 07  when the output of the swing operation signal is stopped from the current time (step S 35 ). Incidentally, after the output of the swing operation signal is stopped, the swing body  120  continues to swing due to inertia while decelerating, and thereafter stops. In a case where the tip end of the arm  132  will reach the loading position P 07  when the output of the swing operation signal is stopped from the current time (step S 35 : YES), the movement processing unit  1112  does not generate the swing operation signal. Namely, in the case where the tip end of the arm  132  reaches the loading position P 07  when the output of the swing operation signal is stopped from the current time, the movement processing unit  1112  prohibits the output of the swing operation signal. Accordingly, the swing body  120  starts decelerating. 
     On the other hand, in a case where the tip end of the arm  132  stops before the loading position P 07  when the output of the swing operation signal is stopped from the current time (step S 35 : NO), the movement processing unit  1112  generates the swing operation signal (step S 36 ). 
     When at least one of the rotation operation signals for the boom  131 , the arm  132 , and the bucket  133  and the swing operation signal for the swing body  120  is generated in the process from step S 27  to step S 36 , the operation signal output unit  1113  outputs the generated operation signal to the hydraulic device  127  (step S 37 ). 
     Then, the vehicle information acquisition unit  1101  acquires vehicle information (step S 38 ). Accordingly, the vehicle information acquisition unit  1101  can acquire the vehicle information after operation by the output operation signal. The control device  128  causes the process to return to step S 31  to repeatedly execute the generation of an operation signal. 
     On the other hand, in step S 27 , when the position P of the tip end portion of the arm  132  has reached the loading position P 07  (step S 27 : YES), the movement processing unit  1112  generates the dump operation signal, and the operation signal output unit  1113  outputs the dump operation signal to the hydraulic device  127  (step S 39 ). Accordingly, the earth contained in the bucket  133  is loaded into the loading target  200 . Incidentally, when the position P of the tip end portion of the arm  132  has reached the loading position P 07 , the swing of the swing body  120  is stopped. 
     Accordingly, the control device  128  ends the automatic excavation and loading control. Alternatively, the control device  128  causes the process to return to step S 1  to repeatedly execute the automatic excavation and loading control unless the loading capacity of the loading target  200  does not exceed the maximum loading capacity. 
     (Operation and Effects) 
     As described above, the control device  128  according to the first embodiment specifies the interference avoidance position P 02  which is located outward from the loading target  200  by a predetermined distance, based on the position and shape of the loading target  200 , to cause only the swing body  120  to be driven such that the bucket  133  reaches the interference avoidance position P 02  and to thus move the bucket  133  to the interference avoidance position P 02 . Thereafter, the control device  128  causes the swing body  120  and the work equipment  130  to be driven, so that the bucket  133  is moved to the excavation position P 05  above the excavation target. Accordingly, the control device  128  can cause the teeth of the bucket  133  to move to the excavation point P 22  while preventing interference between the loading target  200  and the bucket  133 . 
     In addition, after the bucket  133  has reached the interference avoidance position P 02 , the control device  128  according to the first embodiment causes the swing body  120  and the work equipment  130  to be driven, so that the bucket  133  is moved to the swing end position P 04  above the excavation position P 05 . Thereafter, the control device  128  causes only the work equipment  130  to be driven, so that the bucket  133  is moved to the excavation position P 05 . Accordingly, the teeth of the bucket  133  can be brought into contact with the excavation target along a direction where the blade extends. Incidentally, when the bucket  133  hits the excavation target while swing, a lateral force is applied to the blade of the bucket  133 , so that abrasion of the blade and the bending of the work equipment  130  is likely to occur. 
     One embodiment has been described in detail above with reference to the drawings; however, the specific configurations are not limited to those described above, and various design changes and the like can be made. 
     For example, in the control device  128  according to the first embodiment, the depth information is used to specify the loading point P 21 ; however, the present invention is not limited to thereto. In the control device  128  according to another embodiment, the depth information may not be used, the loading target  200  may be provided with the position and azimuth direction calculator, and the loading target specifying unit  1106  may receive the position, azimuth direction, and shape of the loading target  200  output from the position and azimuth direction calculator of the loading target  200 , so that the loading position specifying unit  1111  specifies the loading point P 21 . 
     In addition, in the control device  128  according to the first embodiment, the depth information is used to specify the excavation point P 22 ; however, the present invention is not limited thereto. In the control device  128  according to another embodiment, the excavation position specifying unit  1109  may specify the excavation point P 22  so that the operator can teach the excavation point P 22 . Specifically, the excavation position specifying unit  1109  may store an excavation position when the operator manually performs an excavation operation, to specify the excavation position as the excavation point P 22 . Alternatively, a touch panel type data input terminal device through which an instruction on the excavation point P 22  is given may be provided in the cab  121 , and the excavation position specifying unit  1109  may receive data, on which an instruction is given from the data input terminal device, to specify the excavation point P 22 . 
     In addition, the control device  128  according to the first embodiment performs the automatic excavation and loading control; however, the present invention is not limited thereto. The control device  128  according to another embodiment may perform automatic excavation control, and a loading operation may be manually performed by the operator. 
     In addition, in the control device  128  according to the first embodiment, the excavation point P 22  is specified and an excavation operation is executed after a swing operation toward the excavation point P 22  is performed; however, the present invention is not limited thereto, and the control device  128  may cause a swing operation toward the excavation point P 22  to be executed to end control, and excavation work may be manually performed by the operator. 
     In addition, the control device  128  according to the first embodiment starts, but is not limited to, the automatic excavation and loading control at the no-load swing start position P 01  where the bucket  133  is located above the loading target  200 . In the control device  128  according to another embodiment, when the bucket  133  is at the excavation completion position P 05 ′ and the automatic excavation and loading control is started, the bucket  133  may pass through the interference avoidance position P 02  to move to the loading position P 07 , and after a dump operation is performed, the bucket  133  may pass through the interference avoidance position P 02  to move to the excavation point P 22 . 
     In addition, the loading target specifying unit  1106  of the control device  128  according to the first embodiment specifies the position and shape of the loading target  200  based on the map information generated from the depth information; however, the present invention is not limited thereto. For example, in another embodiment, when the loading target  200  has a positioning function by the GNSS or the like, the loading target specifying unit  1106  may receive, via vehicle-to-vehicle communication, information regarding the position and azimuth direction of the loading target  200  from the loading target  200  which has arrived at a loading point, to specify the position and shape of the loading target  200 . In addition, in another embodiment, when the loading target  200  is an unmanned vehicle controlled by a control system, the loading target specifying unit  1106  may receive information regarding the position and azimuth direction of the loading target  200  from the control system to specify the position and shape of the loading target  200 . 
     In addition, the loading machine  100  according to the first embodiment includes, but is not limited to, the bucket  133 . For example, the loading machine  100  according to another embodiment may include a clam bucket that can open and close a bag-all and a clamshell. 
     In addition, the loading machine  100  according to the first embodiment is, but is not limited to, a manned vehicle operated by the operator who gets thereon. For example, the loading machine  100  according to another embodiment is a remote drive vehicle operating according to an operation signal acquired via communication from a remote operation device which the operator in a remote office operates while watching a screen of a monitor. In this case, a part of functions of the control device  128  may be provided in the remote operation device. 
     The control device of the loading machine according to the present invention can cause the bucket to move to the excavation point while preventing interference between the loading target and the bucket.