To accurately grasp deflection of a telescopic boom.
In a boom working vehicle provided with a telescopic boom turned up and down on a vehicle, when a turned-down angle in turn-down by which a virtual telescopoic boom A0 generating no dead weight deflection is turned down upto a position where a tip of an actual telescopic boom B generating dead weight deflection is located is calculated as a boom deflection angle α, the first turn-up and -down angle θβ in a base end part of the boom B and the second turn-up and -down angle θα in the tip of the boom B are detected respectively, and a difference θb-θa between the detected first and second angles θb, θa is multiplied by a predetermined factor K to calculate the boom deflection angle α =K(θb-θa).
AOKI TOSHIHISA
NISHIMOTO MASASHI
KUSANAGI HIROSUKE
| JPH01256496A | 1989-10-12 | |||
| JPS5612293A | 1981-02-06 | |||
| JPS5548184A | 1980-04-05 | |||
| JPH01259420A | 1989-10-17 |
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