A random search and backtracking procedure for transfer line balancing

Abstract

The optimal logical layout design for a type of machining transfer lines is addressed. Such transfer lines are made of many machine-tools (workstations) located in sequence. On each workstation there are several spindle-heads. A spindle-head does not execute a single operation but a block of machining operations; all operations of a block are executed simultaneously (in parallel). Spindle-heads of the same workstation are activated sequentially in a fixed order. The transfer line design problem considered in the paper consists of finding the best partition in blocks and workstations of the set of all operations to be executed on the line. The objective is to minimize the number of spindle-heads and workstations (i.e. transfer line investment cost). An optimal decision must satisfy a desired productivity rate (cycle time) as well as precedence and compatibility constraints for machining operations. A heuristic algorithm is proposed: it is based on the COMSOAL technique and a backtracking approach. Results from computer testing are reported.

A reactive GRASP and Path Relinking for balancing reconfigurable transfer lines

“…The most significant methods for an exact resolution of the TLBP are (i) linear programming for the logical layout design of modular machining lines (Belmokhtar et al 2006), (ii) dynamic programming (Dolgui et al 1999) and a mixed-integer approach for balancing machining lines with blocks of parallel operations, and (iii) a branch-and-bound procedure for a design problem of transfer lines composed of stations with sequentially activated multi-spindle heads (Dolgui and Ihnatsenka 2009). For large-scale problems, several approximate methods have been designed: (i) priority rules heuristics (Finel et al 2008;Guschinskaya et al 2008) and (ii) metaheuristics, with a GRASP and a genetic algorithm proposed by Dolgui et al (2008) for the transfer lines balancing problem. However, since these articles usually focus on multi-spindle heads and dedicated machines, they do not consider setup times (there is no tool change) or accessibility constraints.…”

A MIP approach for balancing transfer line with complex industrial constraints

“…The most significant methods for an exact resolution of the TLBP are (i) linear programming for the logical layout design of modular machining lines (Belmokhtar, Dolgui, Guschinsky, & Levin, 2006), a dynamic programming (Dolgui et al, 1999) and a mixed integer approach (Dolgui, Finel, Guschinsky, Levin, & Vernadat, 2006) to balancing machining lines with blocks of parallel operations, (ii) a Branch and Bound procedure for a design problem of transfer lines composed of workstations with sequentially activated multi-spindle heads (Dolgui & Ihnatsenka, 2009). For large scale problems, several approximate methods have been designed: (i) priority rules heuristics (Finel, Dolgui, & Vernadat, 2008;Guschinskaya, Dolgui, Guschinsky, & Levin, 2008) and (ii) metaheuristics, for example, see Dolgui, Guschinskaya, and Eremeev (2008), a GRASP method and a genetic algorithm have been proposed for the transfer lines balancing problem. However, since all these cited works focused usually on multi-spindle heads and dedicated machines without tool changes, they did not consider setup times or accessibility constraints.…”

Flow line balancing problem: A survey

“…The equipment to be used in the line is designed (created) on the basis of the obtained task assignment. Such a formulation is especially relevant for the transfer machines and lines equipped with the multi-spindle heads where the tools to be fixed in each head and consequently its machining function is designed on the basis of the tasks grouped together by the assignment procedure [3], [65], [66], [15], [67], [68], [69], [70], [71], [72], [73], [74], [75], [76]. Note that exclusion constraints forbid the assignment of certain tasks to the same equipment and on the contrary, inclusion constraints compel to assign the tasks required the same resource to the same workstation [77].…”