The research attempted to develop safer autonomous crane technology. A cable-based crane with six degrees of freedom was outfitted with a LADAR positioning system that in the future will allow it to become fully autonomous. This will minimize the need for human involvement in construction, increasing efficiency and decreasing related injuries. The research created a specialized safeguard system, adapted to the crane's novel design and constraints, which allowed the crane to register when it is safe to release the load it carries. The crane body was composed of two cable-mounted frames; a "safe" position was defined as any position, which placed no load on the lower frame. After considering several designs based on load cells, string encoders, and vibration sensors, the researchers decided on a system using linear limit switches. The switches register a change in the distance between the upper and lower platforms. When the load is supported by an external structure the switches register a negative change in distance and the Animatics Smart-Motor controlling the holding mechanism receives a positive signal indicating that it is safe to release the load.
Keywords: construction, automation, safety, crane, robot