Production states

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The Production State provides a layer of contextual awareness on top of the Working State.

iVolve systems upload a vehicle's production state data to the server as soon as it has been validated on-board. These states are tracked in real time, but might not be validated (and hence reported) until certain events (such as loading started) have occurred.

For example, when three trucks are working within the queuing radius of a loader, the production states are validated only when the trucks register load passes.

Waiting on Truck (loaders only)

For a loader to be considered Waiting on Truck, both of the following conditions must be met:

• The loader engine must be on.

• No trucks are in the queuing radius.

Queuing Empty (trucks only)

There are several conditions that must all be met for a truck to be considered Queuing:

• The truck must be inside the queuing radius of a loading unit.

• The truck must have been detected (at least once) to be travelling below the maximum allowed speed for initiating queuing.

• The loading unit must be loading another truck or there must be other trucks spotting (or respotting) underneath the loading unit.

The loading unit is configured with a maximum speed for queuing to be initiated. This value is broadcast out to nearby trucks. When a truck falls to that speed (or below) while inside the queuing radius of the loader, the truck tentatively starts recording queuing if there is another truck currently Loading, Spotting, or Respotting at the loader. When queuing has been initiated, the truck can move at any speed within the queuing radius and still be considered queuing assuming the other conditions remain satisfied. Trucks stop recording queuing time when the conditions above are no longer met. Most often, this is because a truck starts spotting.

Trucks stop recording queuing time when the conditions above are no longer met. Most often, this is because a truck starts spotting.

Actual queuing time is not determined until the truck has started loading. This is so Mine4D attributes the queuing time to the correct loading unit. When multiple loading units are in close proximity, a truck could sit stationary inside the queuing radius of a loading unit and not end up being loaded by that unit.

Because loaders do not report queuing time, to calculate queuing time for a given loader you add all of the queuing time reported by the trucks while they were at that loader.

Loader queuing radius

Loading units are configured with (in decreasing order of size) a Queuing Radius and a Loading Radius. These are advertised by the loading unit to nearby trucks.

Occasionally, a truck might be inside the radii of multiple loading units simultaneously. When that happens, the truck tracks but does not report its Production State against both loading units. When the truck starts loading, it discards the tentative records from the other loading unit and reports Production States against the actual loading unit to the server.

For example, in the image below, Truck B is located in the queuing radius of two loaders working in close proximity.

Figure 62-4 Example of two loaders with an overlapping queue radius.

After truck A leaves Loader 2, Truck B changes to Spotting until it is stationary under Loader 2 for the last time prior to entering the Loading state (as detected from the truck OEM interface). The time spent stationary between the completion of Spotting and the start of Loading is classified as Waiting on Loader.

When the start of loading is detected under Loader 2, Truck B discards the time spent in the queuing radius of Loader 1 (as illustrated by the blue timeline) and queuing time is confirmed as the time spent inside the queuing radius of Loader 2 prior to Truck A leaving Loader 2. The Spotting and Waiting on Loader time recorded under Loader 2 is also confirmed when loading commences under Loader 2.

Spotting Empty

Trucks

There are several conditions that must all be met for a truck to be considered Spotting Empty:

• The truck must be inside the queuing radius of the loading unit.

• The truck is not stationary immediately prior to the start of loading.

• The loading unit must not be loading any other trucks.

• There must not be any other trucks spotting or respotting underneath the loading unit.

In general, spotting for a truck starts after the loading unit finishes loading the previous truck and ends after the truck stops (for the last time prior to loading) inside the loading radius of the loading unit. The truck can make several attempts at positioning correctly underneath the loading unit; these attempts are all accumulated into the spotting time of the truck.

After the truck is stationary (for the last time) inside the loading radius, it leaves the Spotting Empty state and starts recording Waiting on Loader.

If there are no other trucks inside the queuing radius of a loading unit, a truck enters the Spotting Empty state as soon as it breaches the queuing radius. Assuming it is the next truck loaded by that loading unit, it does not report any queuing time for that cycle.

Loader

After a loading unit finishes loading a truck, it reports its Production State as Spotting Empty if either of the following conditions are met:

• There is another truck inside its queuing radius that might or might not be moving, or

• There is another truck inside its loading radius that is moving.

The loader stops reporting Spotting Empty in the following scenarios:

• If all trucks leave its queuing radius, or

• If it starts loading a truck, or

• If the truck inside its loading radius is stationary and does not move again prior to loading commencing.

Truck Spotted (loader only)

The time between Spotting Empty and Loading on a loader is classed as Truck Spotted.

This is the time between the truck being stationary inside the loading radius (and not moving again prior to loading commencing) and when loading commences.

It is the same period of time as Waiting on Loader on a truck.

Respotting

Truck

After a truck leaves a loading unit, it generally does not return until after dumping. It is possible, however, that the truck is repositioning to facilitate better loading. Respotting time tentatively accumulates on the truck until one of the following conditions is met:

• The truck dumps; or

• The truck leaves the queuing radius of its loading unit; or

• The truck engine switches off; or

• The truck starts re-loading.

If the truck starts re-loading without having dumped or left the queuing radius or switched the engine off, the time between leaving the loading unit and recommencing loading is reported as respotting time.

If the truck does not reload but rather dumps or leaves the queuing radius or switches the engine off, the time from leaving the loading unit up to that point is reported as Travelling or Stopped Loaded.

A single respotting time is reported for each payload cycle. In the unlikely event that a truck respots multiple times, each respotting duration is aggregated and reported as a single value to the iVolve database.

Loader

After a truck leaves a loading unit, it generally does not return until after dumping. It is possible, however, that the truck is repositioning to facilitate better loading. Respotting time tentatively accumulates on the loading unit until one of the following conditions is met:

• The truck dumps; or

• The truck leaves the queuing radius of its loading unit; or

• The loading unit starts loading another truck; or

• The loading unit starts re-loading the same truck.

If the loading unit starts reloading a truck without it having dumped or left the queuing radius, the time between leaving the loading unit and recommencing loading is reported as respotting time.

If the truck does not re-load but rather dumps or leaves the queuing radius, the time from leaving the loading unit is reported as Waiting on Truck or Spotting Empty, depending on whether or not there are other trucks nearby.

Waiting On Loader (trucks only)

As detailed under Spotting Empty for Trucks, Waiting on Loader is the time the truck is stationary inside the loading radius of a loading unit immediately prior to loading commencing.

If the truck is stationary inside the loading radius and then moves again prior to loading commencing, that initial stationary time is considered Spotting Empty.

Any time the truck is stationary inside the loading radius prior to loading recommencing (for example, when the truck has re-positioned after loading had already commenced) are included in the Respotting time.

Pre-Shutdown (loaders only)

Pre-shutdown is the time the loader spends between the end of the last loading period (or when the loader engine was last switched on, whichever is later) and the loader engine switching off.

There might or might not be trucks in the queuing radius during this time, but because the loader engine ends up being switched off before any other loads are done, it would be erroneous to class this time under any of the other production states.

Pre-shutdown is only ever be reported at the time the engine is actually switched off, and the start time stamp for the record is the end of the last loading record or when the engine was last switched on.

Validation logic

The following flowchart explains the logic used to record truck production states around a loader.

Figure 62-5 Truck production state validation flowchart.

If a truck exits the queuing radius or the truck engine is switched off, any suspected Queuing, Spotting, or Waiting on Loader time is discarded.

Figure 62-6 An example of three trucks working with a loader.