1.1. Fixed Time and Variable Time

So, this cutting and pushing will go together. So, the time required to push, backtrack and maneuver into position, so that is called as a cycle time of the bulldozer.

Cycle time is the total duration taken for a bulldozer to complete one full operation, which includes cutting earth, pushing it to a dumping location, and returning to begin the process again. Each part of this operation is essential for effective earthmoving.

Think of cycle time like a round of golf. Each hole requires you to drive the ball, navigate the course, and return to your starting position before moving to the next hole. Similarly, a bulldozer must complete its task and return, all within a given cycle time.

So, other things are maneuvering, maneuvering in the sense whatever adjustments you do, like for increasing the speed, accelerating or decreasing the speed, changing the gear...

Maneuvering time refers to the adjustments made to the bulldozer during operation, such as changing speeds or gears. This time is crucial because it can affect the overall efficiency of the machine during operation.

Consider driving a car where speeding up and changing gears are essential to maintaining speed and control. If you take too long to change gears, it can slow you down just as it does for a bulldozer when maneuvering.

So, we call this as fixed time, this is fixed time and this one is variable time, your push and backtrack it is called this variable time...

In bulldozer operations, time can be categorized as fixed or variable. Fixed time includes consistent times required for maneuvering, while variable time changes depending on conditions such as haul distance, which is the distance over which the bulldozer must push material. The greater the distance, the longer the variable time.

Imagine a delivery driver: their fixed time includes stopping at traffic lights and making turns, while their variable time might depend on how far they have to drive. The longer the drive, the longer the variable time.

Because it is variable depending upon your haul distance. So, greater your haul distance greater will be a push time and return time or backtrack time.

To accurately calculate push time and backtrack time, you need to understand the haul distance. Push time increases with the distance the material needs to be moved, while backtrack time, which is the return trip, is similarly affected. Therefore, haul distance is a key factor in estimating productivity.

Think about pushing a cart. The farther you need to push it, the more time it will take. Similarly, the bulldozer's efficiency can be impacted by how far it needs to travel to dump its load.

So, to know the push time and the backtrack time, I need to know the travel distance or the dozing distance or the haul distance... So, in the earlier lecture, I discussed about how to determine the speed from the performance chart.

To determine push and backtrack times, you must know the travel or dozing distance and the speed of the machine. Speed can be directly influenced by resistance faced on the project site, which can be sourced from performance charts that detail how different conditions affect machine speed.

Consider riding a bicycle on flat ground versus up a hill. The flat ground allows for faster speeds, while the hill slows you down. Similarly, understanding terrain resistance helps predict the bulldozer's actual speed.

So, now let us see what is this maneuver time?... The maneuver time will depend upon the type of transmission.

Maneuver time varies depending on whether the bulldozer has direct transmission (manual gear change) or an automatic transmission (torque converter). Each type takes a different amount of time to adjust speeds, which in turn affects the overall cycle time of the bulldozer.

Consider using a manual versus an automatic car. An automatic car allows for smoother transitions between speeds, often leading to faster driving times. The same principle applies to maneuvering a bulldozer based on its transmission type.

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