Machine to machine terrain updates (multicast snippets) are required to obtain accurate productivity information when machines are working the same ground. These updates provide accurate productivity for each machine. Machine to machine terrain updates are also required to provide accurate combined productivity information for all the machines that are working together.
Note: When using a TC900 radio combined with multicasting, ensure that the Ethernet port is disabled. Disabling the Ethernet port forces the multicast to use the Remote Access Service (RAS) connection. RAS allows remote users access to the network from a Windows laptop or desktop computer via a modem.
Note: Machine to machine terrain updating can only be used with the IP radio network.
Terrain snippets are multicast from one machine to other machines that are configured to listen to the configured multicast address. The terrain updates that are received are immediately applied and are displayed on the machine that receives the snippets.
Note: Multicast snippets are only sent once. The machine that receives the snippets does not acknowledge the receipt of the snippets. Because the machines are working closely enough to each other, the snippets are expected (and assumed) to be received.
Multicast Snippets are time stamped. The time stamp is critical to accurate update of the as-built surfaces on the machines. The display clock of the monitor display is updated regularly with GPS time. This periodic updating ensures accurate time stamping of the information.
Data File Type and Swath Setup
Configure all machines configured to include a time for each cell in the data file and also configure snippets to include time. Time is used to ensure that the cells in the data file are only updated with new data from the snippets.
"Swath Option" - Determines the type of terrain updates that are performed by the onboard software
Use this setting to specify a data type that includes time, such as the Compaction Time data type.
"Data File Param" - This setting specifies the characteristics of the as-built surface that can be updated, such as current elevation and ore status. Use this setting to set up a data file type.
Multicast Address and Group Setup
A multicast address can be set up either for a restricted group of machines or the address can be set up for all machines. A design file can also contain a group identity. A group identity specifies the destination group for the snippets that are sent to the office. Another use for the group identity is to restrict the machines that use a particular multicast.
"Snip Group Multicast Address" - Specifies the multicast address and port for a group. The multicast address is used to both send and receive multicast snippets.
This setting is used to specify both the multicast address and the group identity. The setting may be configured to include all groups. If the setting is configured in this manner, then there is no restriction on which machines will use the multicast.
Multicast addresses are defined between 224.0.0.0 to 239.255.255.255. Some addresses are reserved. Any addresses in the 224.0.0.0 to 224.0.0.255 range should not be used.
Reference: Refer to the MCU Help file.
"Multicast Address" - Configures the machine to receive snippets only from a specific multicast address
"Multicast Port" - Specifies the port on which multicast snippets can be received
Both of the settings must be present to listen to the multicast address. For machine to machine compaction updates, for example, configure the following settings:
- "Swath Option"
- "Data File Param"
- "Snip Enable"
- "Snip Group Multicast Address"
Configure the swath options to swath the appropriate file type. The "data file type" parameter of the "Swath Option" setting is used to specify an explicit file type.
Refer to the MCU Help file.
When a group of a machine is changed, then the multicast snippets can be either disabled or the snippets can be enabled. Each group can be configured through Cat MineStar System with a unique multicast address.
Note: The multicast group address in the machine configuration file must correspond with the group multicast address set in Cat MineStar System.
Reference: Refer to Systems Operation, RENR9562, "Cat® Terrain Office Software".
Machines can be configured to use multicast snippets for specific groups only. In the previous example, all the machines are working in the "Group 0" site group.
With the Snip Group Multicast Address setting set for Group 0, the machine will receive all multicast snippets for group 0. This fact is true regardless of in which group the machine is configured to work.
If Group 0 snippets are not desired, then disable the "Snip Group Multicast Address" setting that is set for group 0.