Why can a small input move a hydraulic excavator's massive arm? This article treats the pump, control valves, cylinder, hydraulic fluid, sensors, and controller as a single closed loop, covering the pressure/flow/efficiency equations, current technology in construction and agricultural machinery, and electro-hydraulic conversion and current research, with diagrams.
September 11, 2026 Construction Machinery EngineeringA hydraulic excavator is a mobile robot that distributes the rotation of a diesel engine to hydraulic pumps, cylinders, and reduction gears. This article diagrams the kinematics of the boom, arm, and bucket, bucket-edge estimation via IMU, the planetary gears in the upper structure and undercarriage, current ICT/electrification efforts from Komatsu and Caterpillar, and ongoing research into autonomous excavation.
September 3, 2026 Agricultural Machinery EngineeringA tractor is a portable power source that splits the engine's output among wheels/crawlers, the PTO, and the hydraulic three-point linkage. This article explains, as mechanical engineering, traction and slip, tillage-depth control, RTK-GNSS, soil/yield sensors, and where electrification stands.