Since around 1965, many attempts have been made for mechanizing excavation using pneumatic caissons, and in 1987, we initiated development of unmanned excavation construction method using a full-scale remote operation system. Subsequently, in 1988, we obtained successful results through the demonstration experiment conducted with the Asagano River Bridge (substructure) in Tohoku Odan Expressway and established the DREAM construction method (unmanned excavation construction method). DREAM is an abbreviation of Daiho Remote control Excavation Automatic Method. Patent: No. 1795378

In 1997, we developed the multifunctional caisson excavator DREAM II, which is capable of handling a wide range of soil properties from impermeable layer to sand gravel layer and rocks and performing excavation through remote operation. It was adopted for the construction work of the Mabechi River Bridge on the Tohoku Jukan Expressway (substructure) and succeeded in excavating rocks. With this excavator, it is easy to attach a variety of different attachments, such as a rock drill (attachment is performed by human), breaker, and drum cutter in a short period in order to excavate and destroy rocks, boulders, and existing underground structures, in addition to the sand gravel and silt. It is a multifunctional overhead traveling caisson excavator. Patent: No. 3405537

The New DREAM construction method is a new pneumatic caisson method built with the concept of combining unmanned technology for work under high pressure and safety technology according to the work conditions.