Outrigger Force Measure for Mobile Crane Safety Based on Linear Programming Optimization#

Abstract

This work presents a linear programming simplex method for evaluating allowable reaction forces of multiple outriggers with stability constraints. Minimum/maximum pruning approach is adopted to increase the computational efficiency of assessing the outrigger forces when a mobile crane is kept level by the supports of four outriggers. Determining the outrigger forces is an effective means of preventing a mobile crane from tipping over or outrigger failures. Two indices, i.e., moment-index and force-index, which quantify the tendency of tip-over behavior of mobile cranes and examine the bearing capacity of outrigger, are introduced to improve the safety measures. The safety hoist criteria of two mobile crane types equipped with different outriggers are analyzed to demonstrate the feasibility of the proposed scheme. An intelligent anti-upset device that utilizes the outrigger-based stability measures and selectively suppresses critical steering commands in real time is implemented to ensure safe crane operations.