Talk:Multihead weigher

Best Combination Calculation The calculation cost of finding the best combination increases dramatically, depending on the total number of hoppers and the number of hoppers used in the combinations. To get the total number of unique, unordered combinations for a given number of hoppers, start with one hopper having 1 solution, then double the previous number and add 1 for each additional hopper (two hoppers have 3 solutions, three hoppers have 7, four have 15, ect.). To save time, not all the combinations need to be checked. For instance, to avoid having to check every one of the 16,777,215 combinations of a 24 hopper scale, you can just check up to combinations of five hoppers requiring a more manageable 55,454 combinations. In a bagging applications, high and consistent cycle speeds are very important so a well thought out and deterministic algorithm must be constructed. This deterministic requirement also renders pruning techniques useless as the CPU or PLC must be able to make all the calculations in the allotted time even when pruning fails to reduce the possible solutions.

Other Considerations Normally, the goal of the scale is to hit the target weight without going under, with any combination that produces an underweight to be bypassed in favor of overweight solutions (customers are less likely to complain about receiving extra product). However, in many cases the product cannot be allowed to sit in the hoppers for very long before it starts to effect quality. In these instances, the length of time the product has sat in the hopper adds preference to combinations that include it, resulting in combinations that are not the best weight match, but that keep the product fresh. This can often result from product clumping or clogging, causing some hoppers to fill with drastically different amounts of product from other hoppers.

76.160.9.46 (talk) 19:47, 24 September 2009 (UTC)Isaac[reply]

Ad?

This article reads like one big ad. Also, what's with the edit war about who invented it? 109.193.102.101 (talk) 19:02, 9 December 2017 (UTC)[reply]