A sloping surface requires a slope design and a name. Creating a sloping surface generates a design file. A design file needs to be loaded in order for the system to give the machine guidance.
Note: You must save the new slope design to a data card in the Display before you can work to the design.
There are two methods for defining a sloping surface:
- "Two-Points method (2 Points)" defines the master alignment with a starting point and an end point. For more information, refer to "Two-Point Method".
- "Point-and-Direction method (Pt / Dir)" defines the master alignment with a starting point, direction, and grade. For more information, refer to "Point-and-Direction Method".
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| Illustration 1 | g01120173 |
Elements for the sloping surface design | |
Illustration 1 shows the elements of a sloping surface design.
Both methods describe the same surface. Use the method that best suits your requirements. In both methods, the master alignment extends in both directions.
The "2 Points" and "Pt / Dir" dialogs update each other with information. The "Point 1" values and the "Cross Slope" values are the same in both dialogs. Enter Point 2 values. Then change to the "Pt / Dir" dialog in order to see the calculated direction and grade. Check that the values are within the design limits. If you change the Direction setting or change the Grade setting in the "Pt/Dir" dialog, then the change clears the value of "Point 2" in the "2 Points" dialog, as there is not enough information in order to calculate the new position.
Both methods require you to specify a cross slope. The cross slope is the slope at right angles to the direction of the master alignment. A typical cross slope for a road is -3 percent. A positive (+) cross slope rises and a negative (-) cross slope falls as you move away from the defined master alignment.
You must define the cross slope to the left and to the right of the master alignment. The cross slopes to the left and right of the master alignment can be set independently.
Two-Point Method
Point 1 consists of a northing position, an easting position, and an elevation. Point 1 must be on the surface that you want to work to.
Point 2 consists of a northing position, an easting position, and an elevation. Point 2 must be on the surface that you want to work to.
The AccuGrade GPS software connects the first point to the second point. The connecting line is called the master alignment. Use the master alignment for horizontal guidance.
In order to create a sloping surface using the Two-Point method complete the following steps:
- Press the "Design: <Name>" soft key from any of the guidance screens.
The "Select Design File " dialog appears.
- Press the "New Slope" Soft Key. The New Design Sloping Surface dialog appears.
- By default, the "Method: 2 Points" method is selected and the Point 1 position fields are shown. Refer to Illustration 2.
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| Illustration 2 | g01109155 |
- Perform one of the following actions:
- Press the "Here" soft key in order to use the current position of the guidance point that has focus.
One of the "Blade: Left" or "Blade: Right" Soft Keys appears in the Sloping Surface Design dialog. This ensures that you know which blade tip the position is taken from.
Note: If the "Here" soft key is not available, a high accuracy position is not available. For more information, see "Common Problems and Guidelines" in the Troubleshooting Section.
- Use the arrow keys in order to enter the design northing, easting, and elevation values for the Start point. Press the "Next" key in order to move to the next field.
- Press the "Here" soft key in order to use the current position of the guidance point that has focus.
- Press "Point 2".
- Perform one of the following actions:
- Move to the second point and press the "Here" soft key in order to use the current position of the guidance point that has focus.
- Use the arrow keys to enter the design northing, easting, and elevation values for the second point. (Press the "Next" key in order to move to the next field.)
When the two points are entered, the AccuGrade GPS system calculates the direction and grade values. To view the calculated values, press "Method: Pt / Dir".
- Press the "Cross Slope" Soft Key. The "New Design: Sloping Surface" dialog shows the left and right cross slope fields. Refer to Illustration 3.
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| Illustration 3 | g01109157 |
- Perform one of the following actions:
- Use the arrow keys to enter the left cross slope value.
- Press the "Level" Soft Key.
- Press the "Next" key in order to move to the "Right" field.
- Specify the right cross slope as described in Step 8.
- Press the "OK" key. The "Design Name" dialog appears. Refer to Illustration 4.
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| Illustration 4 | g01109158 |
- The AccuGrade GPS system provides a default name. Use the arrow keys to change the default design name.
- Press the "OK" key in order to accept the name and return to the "Select Design File" dialog. The new design file is highlighted.
- Press the "OK" key in order to load the new sloping surface design.
Point-and-Direction Method
Instead of entering a second point, you can enter the direction and grade. The specified values are used to create the master alignment of the sloping surface.
The direction specifies the bearing of the master alignment.
The grade is the grade at which the master alignment rises or falls along the specified bearing. You can enter the grade as a ratio or a percentage.
As you travel in the specified direction, a positive (+) grade rises and a negative (-) grade falls.
The grade in a Grade field is normally expressed as a ratio. A grade of 1:1000 (or 0.1 percent) is nearly level and a grade of 1:8 (or 12.5 percent) is very steep for a road.
Note: For any site, there is a grade that it is too steep for machines to operate at. Find out what this is for your workplace and make sure that you do not create roads steeper than this.
To enter a sloping surface using the Point-and-Direction method complete the following steps:
- Press the "Design: <Name>" soft key from the guidance screens. The "Select Design File" dialog appears.
- Press the "New Slope" soft key. The "New Design: Sloping Surface" dialog appears.
- Press the "Method: 2 Points" Soft Key. The soft key changes to "Method: Pt / Dir" and the Point position fields are shown in Illustration 5.
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| Illustration 5 | g01109162 |
- Perform one of the following actions:
- Press the "Here" soft key in order to use the current position of the guidance point that has focus.
One of the "Blade: Left" or "Blade: Right" Soft Keys appears in the Level Surface Design dialog. This ensures that you know which blade tip the position is taken from.
Note: If the "Here" soft key is not available, it means that a high accuracy position is not available. For more information, refer to Operation and Maintanence Manual, "Troubleshooting Techniques".
- Use the arrow keys to enter the design northing, easting, and elevation values. (Press the "Next" key in order to move to the next field.)
- Press the "Here" soft key in order to use the current position of the guidance point that has focus.
- Press the "Direction" Soft Key. The "New Design: Sloping Surface" dialog shows the direction and grade fields. Refer to Illustration 6.
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| Illustration 6 | g01109163 |
- Use the arrow keys to enter the direction value in decimal degrees. This defines the master alignment clockwise from north (for example, 123.5 degrees).
0 degrees - North
90 degrees - East
180 degrees - South
270 degrees - West
- Press the "Next" key in order to move to the "Grade" field. The "Level" soft key appears.
- Do one of the following actions:
- Use the arrow keys to enter the grade value.
- Press the "Level" Soft Key.
- Press the "Cross Slope" Soft Key. The "New Design: Sloping Surface" dialog shows the left and right cross slope fields. Refer to Illustration 7.
Use the arrow keys in order to enter the left cross slope value.
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| Illustration 7 | g01109164 |
- Press the "Next" key in order to move to the Right field.
- Specify the right cross slope as described in Step 9.
- Press the "OK" key.
You can enter the point, direction, and cross slope values in any order. When you switch screens in the dialog or press the "OK" key, the software checks that the fields are valid.
Note: If required data is missing or invalid, you are warned. The appropriate screen is displayed so that you can enter the information.
If the data is valid, the "Design Name" dialog appears. Refer to Illustration 8.
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| Illustration 8 | g01109165 |
- The AccuGrade GPS system provides a default name. Use the arrow keys in order to change this.
- Press the "OK" key in order to accept the name and return to the "Select Design File" dialog. The new design file is highlighted.
- Press the "OK" key in order to load the new sloping surface design.