Abstract: A rock bolt includes a hollow body and a gap along a length of the hollow body. At least one strain gauge is affixed to an inner surface of the rock bolt and is accessible from the gap. The rock bolt may include a data logger within the hollow body and coupled to receive signals from one or more strain gauges, and to record these signals in a memory. The data logger may comprise a data port adapted to be accessible from the outside of a bore hole into which the rock bolt is inserted. The data logger also may include at least one of a visual and auditory alarm. A graphic user interface software program can be used to download data from the data logger and set certain operating parameters of the data logger.

Abstract: An onboard power generation apparatus for a hoist conveyance includes a drive wheel carried by the conveyance. The drive wheel is positioned to engage the surface of a stationary structure adjacent the conveyance, such as a shaft guide, so that movement of the conveyance relative to the structure causes rotation of the drive wheel. A charging generator coupled to the drive wheel is operable to produce an electric current upon rotation of the drive wheel. A battery may be electrically connected to the generator so that the generator provides an electric current to recharge the battery. The drive wheel may be mounted for movement relative to the conveyance with biasing mechanism for resiliently biasing the drive wheel toward the surface of the adjacent structure.

Abstract: An onboard power generation apparatus for a hoist conveyance includes a drive wheel carried by the conveyance. The drive wheel is positioned to engage the surface of a stationary structure adjacent the conveyance, such as a shaft guide, so that movement of the conveyance relative to the structure causes rotation of the drive wheel. A charging generator coupled to the drive wheel is operable to produce an electric current upon rotation of the drive wheel. A battery may be electrically connected to the generator so that the generator provides an electric current to recharge the battery. The drive wheel may be mounted for movement relative to the conveyance with biasing mechanism for resiliently biasing the drive wheel toward the surface of the adjacent structure.