Horizontal Directional Drilling (HDD) is a type of underground pipeline construction equipment based on “trenchless technology”. Its core features are “precise direction control and no surface damage” — it can realize drilling, reaming and backhaul operations for underground pipelines without damaging roads, vegetation and buildings. Its drilling depth can range from several meters to hundreds of meters, and the applicable diameter spans from centimeter-level ( communication optical cables) to meter-level (large-diameter oil transmission pipelines). It is capable of handling various stratum conditions such as clay, sand and pebble layers. As a key piece of equipment, it is widely used in underground pipeline construction for urban renewal, transportation infrastructure, energy transmission and other fields.