[rules-users] [Optaplanner] Scheduling + VRP

[Mats Norén]

Thanks, 
I'll give number three a try :-)
Is there an example with two planning entities?

Regards,
Mats

1 dec 2013 kl. 10:58 skrev Geoffrey De Smet <ge0ffrey.spam at gmail.com>:

> 
> On 30-11-13 15:02, Mats Norén wrote:
>> Hi,
>> I'm looking for an example that does both scheduling and vrp.
> No example of that combination yet.
>> I have workers with certain skills and I have goods (which require a particular skill set) to be delivered or picked up within certain time windows.
>> Each worker work in a team.
>> The team should if possible be assigned to the same delivery/pickup.
>> The workers work in shifts and by law has to have breaks etc.
>> I want to create a schedule that assigns workers/teams to deliveries/pickups and stay within the time windows as well as optimizing the distance travelled.
>> I thought about the nurse rostering example together with cvrptw but the nurse rostering uses shifts (day, night).
>> 
>> Do I have to do it in two steps? First VRP and then try to assign the workers?
> In practice, I often see this happening in 2 separate, sequential 
> planning problems (or phases),
> but that's just because of Conway's law:
>   "organizations which design systems ... are constrained to produce 
> designs which are copies of the communication structures of these 
> organizations"
> 
> 2 phases is probably suboptimal, because the limitations on the second 
> phase influence the planning of the first phase.
> There are 3 ways to handle that:
> 
> 1) Ignore it that 2 phases is suboptimal. You 'll have better results 
> that the old system already. You can tweak it by adding some constraints 
> in phase 1 that make it easier for phase 2.
> 
> 2) Bender's decomposition. Basically ping-pong between phase 1 and phase 
> 2 (where the result of phase 2 adds constraints in phase 1). Not yet 
> supported out-of-the-box by OptaPlanner, but probably a domain specific 
> pita to implement.
> 
> 3) Do it all in 1 phase. OptaPlanner 6 has been written to handle 
> multiple planning entity classes and multiple planning variables, so 
> it's definitely possible. You 'll like need to add course grained moves 
> to get things to change for phase 1 in a way that works for phase 2, to 
> avoid getting stuck in a "score trap" (see docs).
> 
> I am a strong believer in approach 3). If you go that way, let me know 
> how it works out: I need cases to prove that the human planners that 
> follow Conway's law should not limit our potential when automating this.
> But the conservative choice is 1).
> 
> In any case, I recommend to prototype phase 1 first.
> 
>> 
>> The only hard facts are the workers worktime and the goods delivery/pickup time.
>> 
>> Any suggestions?
>> 
>> Best regards,
>> Mats
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