All posts by juanantm

Martian logistics, because colonizing new planets is not all fun and games

Today while eating the merienda (remember guys, eating five times a day is important for a healthy life) I saw a chapter of Big Band Theory about Sheldon Cooper applying to a Mars colonization project. It made me think about how the Mars colonization would be. Humankind has dreamt on colonizing mars since decades ago, but it always seemed imposible til now, when we start to consider it not only as a possibility, but as a must… So, how would it be?

First of all, why should we go to Mars? A colony without a purpose would be senseless. Obviously an initial investment that will be basically without financial return would be needed, but this dependency on subventions cannot last forever; “donors” (states, entrepreneurs, philanthropic funds) would agree to bear the project only if it should lead to an entrepreneurial venture capable of ensuring its functioning independently.

This is how would look the habitations and greenhouses zones of the colony

An economic analysis of a colony, in order to be set within a framework as realistic as possible, had to be developed upon a scenario addressing, by priority, the following selection criteria:

  • Supplying products or services which would be specifically Martian, so as to mitigate competition from other locations (including terrestrial ones).
  • Discarding exports involving interplanetary transport of bulky masses (metals, semi-finished products), unless their value justifies the cost of travel (paying passengers, possibly some rare metals).

But this would only be the beginning of the problem. How would the habitants live?Which initial investment would be needed? How could we achieve a profitable operation over the long run? Which would be the cost of transfer of passengers to Mars? Could the colony comercialize Mars tourism?

All this questions, and far more, are answered in this interesting article, where a very detailed model of how the economy and the supply logistics of a martian proto-colony would operate is shown. The article is really worth the read, not only to the scienfiction nerds like me, but to everyone interested in logistics.

We know how logistics work on Earth, but, what about Mars?

Rubber ducks, and how to see the positive side of a logistics disaster

Across the vast expanses of water making up more than two thirds of the planet, some 50,000 shipping vessels are bustling away, delivering the cargo that makes much of our world tick.

Dwarfing cruiseliners in size, freight behemoths transport millions of containers hundreds of thousands of kilometers a day – some ships can carry 20,000 at a time – while 33 million exist in total.

So, it is perhaps no surprise that not all make it to their destination safely.


A containment of some 29,000 plastic yellow ducks, red beavers, blue turtles and green frogs were washed into the Pacific in 1992, the little toys began appearing on beaches around the world, from the west coast of America, to South America, Australia, and by 2007, Europe.

The travels of the ducks was used by oceangrapher Curtis Ebbesmeyer to map the global currents of our oceans, though they were already working on a model, tracking 61,000 Nike trainers lost overboard in 1990.


So in this way, a big disaster in the logistics process served as a way to better understand how the ocean currents works, and helped the researchers a lot.

Wanna look ready for summer? Become an Amazon picker!

Work Hard – Have Fun – Make History

Few days ago I was watching the famous spanish TV program “El Intermedio” meanwhile I was having the dinner, as I do every night, when suddenly they started talking about Amazon. We have all heard about Amazon logistics: enormous warehouses, almost infinite SKUs, deliveries all over the world… It is simply impresive. But what I heard about them in the TV was not that impresive.

An average picker walks around 24 km a day. They are expected to collect a customer order every 33 seconds, or 50 and 60 items per hour at the Amazon plant. You are bound to get, to the point of exhaustion, up to 130 items per hour. This way you will be a model picker. Physical fatigue forces you to not think and provokes a void in your mind. Walk, pick, come back, walk, pick, come back.


Nichole Gracely, which was one of Amazon’s best order pickers in the UK warehouses, describes her work in amazon as the following:

As an ordinary order picker, I was toiling in some remote corner of the warehouse, alone for 10 hours, with my every move being monitored by management on a computer screen.

As she says in the follwong interview, they are subjected to ‘unbelievable’ pressure to meet efficiency targets. They even have the toilet breaks timed.

This information makes me question where is the balance between efficiency and workers health. The best and most efficient arrangment may be in conflict with the workers needs. This, sometimes, may be forgoten by the managers.

Santa’s warehouse logistics: Things just got serious

A quick analysis of the Santa Claus’ huge warehouse

We all know Santa Claus, also known as Saint Nicholas, or Papá Noel here in Spain. He delivers presents (or coal) to all the kids around the world the night of the 24th of December. But… have any of you ever thought about the facilities he must have to storage all the presents he manufactures in his toy factories? Well, you don’t need to, as in a moment of boredom I have already done it!

It is well known that Santa lives in the Pole North, so we can assume he has there also the warehouse where he stores the presents. I tried to do some digging in the internet about land prices in the Pole North, but sadly it does not appear. Anyway, we can safely assume it must be really cheap the cost of the land over there, so the space in the warehouse is definitely not a problem.

As Santa only needs to deliver once a year his whole inventory, a LIFO storage system, with all the pallets on the floor would be the most suitable and easiest arrangement. No aisles needed neither, remember you are delivering all your storage at once, once a year, no need of picking in between. So just a big island of pallets on the floor. Because of the cheap prices of the land, automatization would significantly increase the costs due the high ammount of pallets Santa handles, and would suppose a incredible high investment he can easily avoid by just storing at floor level.

Sin título-1
Santa’s warehouse arrangement. He likes keeping things simple.

But, how many pallets? Lets assume the mean number of present boxes per pallet is of 50 units. Just one level of pallets, to avoid crushment (in Pole North we have plenty of space anyway). Based on the global ammount of kids (0-15 years old), delivering a present per kid, it would be needed just around 45.7 million pallets. Taking into account the proportions of an europallet (Saint Nicholas is european after all), it is translated into a pallet island of 43.87 square kilometers. That is around one third of the city of Valencia, or 13 times Central Park.

excel santa
Calculations for the pallets needed

This calculations only lead us to many more questions. How many elves (the Santa’s pickers) would he need for Christmas? What would be the holding costs? Which picking methods does he use? How many SKUs is he holding?

I think we should skip the Ford’s visit and go to the Santa’s warehouse.

Traffic light logistics: when you become the package.

While I was studying my industrial electronics and automatics engineer degree, I had to program a cross street traffic lights for a simulation. The task was not particularly difficult (I was just programming a couple of traffic lights for an intersection), but it made me realize how difficult must be to control not just one intersection, but all of them in a big city like Valencia (or worse, Madrid).

Just in the same way in a warehouse you have to take into account the holding costs, in a intersection of streets, if the red-green light periods of the traffic lights are too long,  retentions will be created, and if they are too short, only a few cars, the ones in first line, will cross, due to the delay in the reaction time of the drivers. So a proper lenght has to be found, and it depends on the traffic flux, which is also dependent on the area, hour and day, so a constant revision of the periods is needed.

By the way, we don’t have to forget the yellow light. Sometimes are not needed, if there is no “dilemma zone“, but when needed, if it is too short, some drivers will cross in red and it may cause accidents (although it also increases ticket revenue if you put a camera).

A propper traffic light system is not a joke, the Los Angeles synchronized whole-city-traffic light system “increases travel speeds by 16 percent and reduce travel time by 12 percent. And because of reduced idling time, the city says it will save 1 million metric tons of carbon from entering the atmosphere”.

In case you wanna know a bit more about how all this works, here there is a video of the Los Angeles Department of Transportation Automated Traffic Surveillance and Control Center.

Hope next time you see a traffic light, you look at it with different eyes.

KFC runs out of chicken: Is the end near?

The chicken crossed the road, just not to KFC restaurants

Fancy some fried chicken? No problem, go to KFC, the world’s second-largest restaurant chain (by sales), with almost 20,000 locations globally. It is so popular that in Japan has become a tradition to have the christmass meal there, and getting the KFC special Christmas dinner often requires ordering it weeks in advance, or wait in line, sometimes for hours.

So now imagine yourself waiting for your traditional christmass dinner at KFC with all the family together, just to realize there is no chicken, destroying all the magical spirit of the christmass. Well, something like that has happened in the UK (maybe not as tragic), as more than half of the KFC restaurants in the country, over 600, have run out of chicken.

The 14th of February hundreds of the UK branches were forced to shut their doors when their chicken supply stopped. DHL, in partnership with Quick Service Logistics, took over the KFC supply contract from long term partner Bidvest Logistics, food distribution firm with years of experience that has been succesfully working with the brand for eight years. The new delivery company struggled to cope with supplying 900 shops.


The root cause of the problem is still uncertain, and it is not known yet if it’s a supply/stocking problem or a distribution one. The fact that there are no other companies that are lacking chicken shouldn’t make us think it is a transportation problem and discard a supply one.

It takes 8 weeks to raise a chicken, and chicken farms will be very careful not to hatch any surplus chickens that then crash the wholesale market in eight weeks. KFC don’t use a single supplier, so no chicken supplier can forecast the KFC demand on their own and so rely on the forecasting from KFC to plan production. So if the forecasts were messed up, then a long running shortage for several weeks is possible, unless KFC authorizes expensive and potentially out of specification purchases from the wholesale market.

We can see in this blog lots of interesting articles about how logistics work effectively in different business, but articles about what happens when things are not done well are far more scarce. Due to this error in the logistics, KFC is having huge loses on the UK, and it is not known if the contract will return to Bidvest.

Time will tell.