How is assembly line balancing performed and what are the challenges?

Line balancing distributes work content across stations to match takt time while minimizing total stations and achieving even workloads. Process involves: Breaking total work into elemental tasks with time standards, considering precedence constraints (what must precede what), grouping tasks to fill station cycle times without exceeding takt, and considering ergonomic factors. Challenges include: Option/variant content variation (different work times), precedence constraints limiting groupings, workstation physical constraints, ergonomic limits on repetitive motion, and supporting multiple models with different content. Mixed-model lines require balancing across average mix while handling extremes. Software tools optimize large balancing problems.