figure 1 An excavator 2a is shown as an earth-moving machine having a position determination system according to the present invention. The excavator 2a runs on the ground surface 10 to be excavated. For example, excavation work is part of constructing roads or laying lines or pipelines. A supply pipeline 1 as an underground object has been laid under the ground surface to be excavated, where the supply pipeline 1 emits electromagnetic fields. The excavator 2a has an excavator arm 3a, which has a first arm portion 11a and a second arm portion 12a as a working portion, and a bucket 13a, all of which can be adjusted in height by hydraulic cylinders. The second arm portion 12a is provided with a fixing portion 4a, a flexible connector 7a, and a detection portion 5a as components of the position determination system according to the present invention, where the fixing portion 4a is configured to be magnetically fixed to the second arm portion The upper shell is also used by the indicating part of the position determination system (not shown). The detecting portion 5a is indirectly arranged on the fixing portion 4a via the flexible connecting piece 7a in such a way that the detecting portion 5a can swing in a horizontal plane like a pendulum. Since the connecting piece 7a is constructed in a flexible manner, the orientation of the detecting portion 5a is realized under the action of gravity. Therefore, in the various postures of the excavator arm 3a (the second posture is shown by a dashed line), the detection portion 5a is oriented perpendicular to the ground surface 10 and the supply line 1. The detection part 5a is configured to detect electromagnetic radiation. As long as the radiation is detected, the detection is forwarded to the control device of the excavator 2a through the indicating part provided in the fixed part 4a in the form of a housing. This forwarding is achieved by radio (such as a Bluetooth interface). It is also possible to arrange the indicating part and the detecting part 5a in a common housing, for example, on a circuit board.
 figure 2 An excavator 2a is also shown as an earth-moving machine as a component of the position determination system of the present invention. The round metal sheet 4b as the fixed part is welded to the second arm 11b of the excavator arm 3b; figure 1 , The detection part 5b is arranged on the circular metal sheet 4b in a pendulum manner through a flexible connecting piece 7b. The indication part of the position measurement system is not shown.
 image 3 It shows another pendulum-like arrangement of the detection part of the position determination system of the present invention on its fixed part. The fixing portion is fixed to the excavator arm 3c and is configured as a frame 4c, in which the detecting portion 5c is suspended in a swingable manner about the axis 9.
 Figure 4 An excavator arm 3b is shown with the components of the position determination system of the present invention. It can be seen from the figure that the detection part 5d of the position determination system is arranged in such a way that it is arranged as close as possible to the bucket 13d, but a certain distance is left so that it will not touch the bucket. A reflective element 14 is also provided on the excavator arm 3d. The reflecting element 14 can be measured by a tachymeter to determine the position of the element. The excavator arm 3d is also equipped with the following sensors, namely, pressure sensors 15, 15', 15", which are correspondingly assigned to hydraulic cylinders (not shown) not shown, which are used to adjust the excavator arm 3d The first arm 11d and the second arm 12d and the bucket 13d. In addition, the first arm 11d, the second arm 12d and the bucket 13d are equipped with tilt sensors. The tilt sensor is not shown in the figure. By means of reflective elements 14 and these sensors can calculate the position of the lower edge of the bucket. If the distance to the underground object is now determined by the position measurement system, then combine the knowledge of the position of the excavator arm 3d, and then combine the maintenance of the excavator arm 3d The recognition of the position of the detection unit 5d with a fixed positional relationship can determine the depth of the object.
 Figure 5 The excavator in digs up earth at 10' on the surface. On the excavator arm, the detecting portion 5e is provided on the arm portion 12e in a pendulum manner via the fixing portion 4e and the connecting portion 7e, and the arm portion 12e is rotatably connected to the bucket 13e. According to the follow-up Figure 7E , The detection unit 5e has an antenna and a laser rangefinder. By measuring the distance to the ground (here, the distance to the ground 10" obtained by excavation) with the help of the laser rangefinder, the depth of the object can be determined based on the object distance calculated from the detection data of the detection unit 5e. This figure shows that the detecting portion 5e is provided on the arm portion 12e through the connecting piece 7e and the fixing portion 4e in such a way that the detecting portion 5e will not touch the bucket 13e even when the bucket 13e is completely folded, and thus Protect it from being damaged by the bucket 13e. When the arm 12e retreats (as shown by the dotted line), the detection part is attached to the arm. When the excavator is transported (that is, when the excavator is not in use) Simply remove the detection part 5e and other optional components. It is also possible to provide a fixing device for the detection part 5e so that the detection part 5e can be fixed and does not swing (for example, when the excavator is transported or has been recorded accurately enough In the case of underground objects in the area).
 Image 6 An embodiment of the position determination system of the present invention is shown, which has a fixing part configured for a calculation part as a housing 4f. The detecting portion 5f is provided on the housing 4f in a pendulum manner via a connecting piece 7f. According to this figure, this fixed part is attached to the front boom part 12f of the excavator 2f. The housing 4f as the fixed part is provided with a magnet bar on the back plate of the housing, and the housing 4f is magnetically fixed to the arm 12f located at the front by the magnet bar. The magnetic fixation allows quick and easy installation and removal of the housing 4f. In the cab of the excavator 2f, an instruction unit 6f including a graphic display is provided. The instruction part 6f is, for example, in accordance with the following Figure 8 The embodiment shown in is constructed.
 Figure 7A-7F Shows in more detail Image 6 The detection part 5f, the connecting piece 7f and the fixing part in the middle. The fixing part is configured as the battery compartment 16 and the housing 4f for the calculation part 8f (see Figure 7C ).
 The connecting piece 7f is constructed in the manner of a bellows and is made of a flexible plastic material. The connecting piece 7f is firmly screwed not only with the housing 18 of the detecting part 5f but also with the fixing part through the screw parts 17, 17'.
 The detection part 5f has a first antenna 20a and a second antenna 20b, and these antennas are arranged in the housing 18 in a manner to maintain a known axial distance d from each other. Figure 7E An embodiment of the detection unit is shown, which also has first and second antennas 20 a ′, 20 b ′ (they also keep a fixed distance from each other), and additionally has a laser rangefinder 19. For example, in a single-coil or multi-coil manner, these antennas are configured as a single-axis antenna 20c, a biaxial antenna 20d, or a triaxial antenna 20e, such as Figure 7F Shown. The time-varying magnetic field of the underground wire induces a voltage between the ends of one or more coils of these antennas, and the induced voltage depends on the magnitude of the magnetic field. In the calculation unit 8f, the distance value of the wire is derived based on the output of these antennas. The derivation can for example be expressed as simply assigning distance values to the outputs of these antennas.
 in Figure 8 An example of the indicating unit 6g of the position measurement system of the present invention is shown in FIG. The indicating portion 6g has a graphic display 6g' and is configured as an indicating and control unit. A plurality of LEDs are formed on the graphic display 6g' as visual indication devices, and a plurality of switch buttons are also formed for selecting settings. Here, the switch button includes a "mute" switch button 21, which is used to silence the sound alarm (here, in addition to the visual alarm signal, the sound alarm is also set). The position determination system can be switched to "standby" or "operation" by another switch button 22. The LED 23 associated with the switch button lights up to indicate which setting is active. Two other LEDs 24 show the battery status of the calculating part 8f and the detecting part 5f and the battery status of the display 6g'. The plurality of LEDs 25 located in the upper area of the display 6g' are visual displays related to the distance information of the detected underground objects. They are divided into three color segments (green, yellow, red). If the green LED 25' lights up, it indicates that an underground object has been detected, but the object is at a distance of 30 cm away. The yellow LED 25" lights up to indicate that the object is now within 30cm. The red LED 25" lights up to indicate that the object is within 10cm and is in the highest alarm level.