Development of a Soft Excavator, Phase 3. Annual Report January 1985-January 1986

摘要

Damage to gas and other utility distribution lines by excavation equipment is a costly and potentially dangerous problem. IRRI, under contract to GRI has completed Phases I, II, and III in the development of a soft excavator for the purpose of excavating productively without damaging underground utilities. Digging is achieved by imparting a precessing motion to a 9-inch diameter cylinder while maintaining constant down-force and applying vacuum removal of spoil at the point of generation in the digging-head. Actual penetration rates with an improved breadboard tool was as high as 4 ft/min (1.7 cu ft/min) during Phase I. Phase II focused on tests of the breadboard, and design and manufacture of a prototype soft excavator tool and utility vehicle. Phase III was devoted to shakedown tests and consequent modifications to the engineering prototype tool and vehicle. Preliminary field demonstrations with utility companies revealed a limited range of soil conditions for which digging performance was productive. An economic analysis and market survey revealed that significant improvements in productivity are far more important to the industry than is prevention of third party damage. Hence, Ingersoll-Rand has judged that the soft excavator in its current embodiment is not marketable.