Railroads are typically constructed to include a pair of elongated, substantially parallel rails, which are coupled to a plurality of laterally extending ties. The ties are disposed on a ballast bed of hard particulate material such as gravel. Over time, normal wear and tear on the railroad may require track maintenance operations to correct rail deviations.
Rail vehicles for track maintenance operations include workheads for performing the desired track maintenance, such as spike pulling, track stabilizing, or other maintenance operations. Ballast tamping is one such maintenance operation, and is itself conventionally understood to comprise various modes of operation, such as indexing, where the tamping machine is advanced to an appropriate position with respect to the laterally extending ties, and cycling (also called “tamping”), where components associated with the workhead are driven into the ballast to a predetermined depth and “squeezed” to compact the ballast.
Historically, tamping machines have either been indexing or continuous in operation. Conventional indexing machines come to a complete stop while tamping takes place, whereas conventional continuous machines involve the main vehicle frame continuing forward during tamping and a workhead is moved independently with respect to the tamping machine. Previous improvements related to continuous tamping have been directed to maintaining the frame of the tamping machine in continuous movement, or directed to increasing the operational speed of the machine. However, these improvements increase the complexity of the system, and the gain in productivity does not always meet expectations. It is desirable to further improve tamping cycle productivity by prioritizing production speed over continuous machine movement, such that the overall productivity of the tamping cycle is improved despite deficiencies in various steps of the cycle.