A planetary gear retrieval system for pulling a sled at a constant velocity along an interior of a pipe, and a sled for applying a coating material to the interior of the large-diameter pipe. The planetary gear retrieval system is connected to the sled via a chain, and has a network of gears controlled by a first variable speed microcontroller. A spinner on a linear oscillating plate provided on the sled is controlled by a second variable speed microcontroller. The first and second microcontrollers are programmable to be synchronized with one another so as to pull the sled at a desired constant rate and achieve a desired number of passes of the spinner along a given length of pipe while the sled is pulled at the desired rate.