Sardana control application

Yesterday, one of the gurus of Tango and project leader of Sardana presents an internal seminar for the control system section in Alba:

One of the images that I like more to represent the meaning of this Sardana package is one:

In the upper layer we have the area of the presentation layer, where we develop taurus. Is the screens with the user interacts. How you manage the coordination of the movements together with the acquisition in not the business of the final user. Even more, they don't case about how you did it, they only want the thing running with reliability.


Also there is the possibility for the user to have a user interface based in a command line screen, and for this there is spock (is an ipython console with the philosophy of spec):

But furthermore than a console usage of a beamline, the GeneralBeamlineGui is the best example of the use of taurus, together with Sardana to have a full control of a beamline to do the experiements. With a layout of the beamline the user can click on the elements to know the details of each instrument in the beamline. 

Christmas shutdown

Today, more specific, this night will start the Christmas shutdown.

This are running well, and it's very interesting to have the shutdown were they are planned...

Postscriptum: How many synchrotrons can show an snapshot of the machine status with absolutely all the frontends open? But they have much more beamlines. The probability to have this situation is much bigger being in beamlines commissioning and having only 7 beamlines.

Alba's Director vacancy (III)

Official announcement! We will have to get use about this kind of things. It's very grateful to have a different think than weird rumours that you don't know if it's true or fake.


Focus on the President of the executive commission communication to all the Alba's workers: it's official that we already have an acting director. That is an worker who is already knowing in Alba, who will carry the directorate duties. It's a person who is already working here.


The CELLS Rector Council have decide to open again the position to call for directors. This will take some time. Let see how the things will go in the behaviour of this little ecosystem of the synchrotron.

European Spallation Source, Bilbao

In Spain, is under construction another science facility different and complementary to Alba synchrotron: An Spallation Source in Bilbao.

This facility is one of the options to have a neutron source, and it's the only option that doesn't have a nuclear plant to get this fast free neutrons.

In the media area of the ESSBilbao website, there is a video with an explanation of the project. That is much more than what we have in Alba (I've seen a very few official video of our facility, but they are not promoted in our website).

Another video that looks interesting to follow what's a spallation source, is from the ESS Scandinavia, from where the Bilbao's project is child.

An Spallator can be resumed as a large proton linear accelerator with a metal target at the end of the line, where the impact of the fast protons produces free and fast neutrons in many directions.

There is another video, a bit larger, that shows something more about an Spallation source:

Finally, I like to mention that the website of ESS-Bilbao is in 3 languages: International English and the two local languages: Basque and Spanish. With this, some local people without knowing English can read the website content (perhaps because the study when is Spain the foreign language was French, not all the public must be young-scientist). In Alba, everything is in English, we are not open enough to one closest public.

debt, money and credit

Two months a go I have write some ideas about money. Yesterday I read the Spanish translation of an interview to David Graeber (I think this is the original in English). I didn't read before about this guy, who is described in Wikipedia as "American anthropologist and anarchist".


It's interesting what he says about the origin of the money, specially the sequence between credit, debt and money. Before the existence of money, there where already credit and debt. And the coinage of the money was (at least in the mentioned cases) the solution to pay the troops. The people who produces something, had something to exchange, but the troops needs coins to get things. This coins are after requested by the boss to the people to pay the taxes to pay the troops.


It's also interesting from this interview reading that the debt make slaves. How the extortion can create and produce a relation of debt. Changing what is said there with the word "Mafiosi" by "the markets", and "extortion" by "speculation" you can describe the current situation of this "European debt crisis".


But still the money doesn't exist. Yes, today the banknotes and the e-cash are used all the days by (almost) every one. We all are in the loop, specially in the loop of the debt more than in the richness. Renting your arms in a factory for a salary, is the way of debt. Non of the ones who have accumulated richness have get it working hard 40 years in a factory. We lived over our possibilities? Well, you can be agree or not, the thing is that the ones who says that to the PIGS are still living with in the same good way than before.


Governments have to generate debt to pay the black holes of the banks, and this debt is bought by the banks who next will request money to the governments. This is like a pyramidal trick, there is no way to get out of it. Maybe only with the system reset.

Alba's Director vacancy (II)

Finally! We have got an official announcement! Today the President of the executive commission (just above the directors position) have sent an email to all the Alba's stuff.


Then: official announcement that we don't have director. Yesterday I have wrote about this. Also it's official that the Rector Council of the CELLS consortium have nominated a new director, but some paperwork pending. Finally this selected person have rejected the position due to personal reasons.


Now the position is now open again, and the President have said that he will keep us informed. Only with this it's a big change in the relation with the workers.


This synchrotron project will continue as it's planned. In a few months, we will receive the first scientist to use the facility. I feel this change is the beginning of a new era in Alba. I hope I'm not being to optimistic, many inertias must change. Cooperate in the efforts for this start up, means many things, including don't refuse a proposal of agreement about work condition because it comes from the workers side.


With common sense and good intentions we can reach the balance, having back the smell the illusion in the corridors of this synchrotron.

Alba's Director vacancy

Today the Alba's director has sent an email to all staff. In this email he had announced that he is leaving the director's position. Is also written in this email that this has been plan, by him, due to the enter in operation. But, as far as the first users will arrive later Easter, this announcement doesn't mach.


We are still in commissioning, and the maximum current accumulated in the storage ring is 200mA. We are still working hard and doing our best to have the machine up and running at 400mA, the design and expected accumulated current. Some of the problems of this institution didn't have relation with synchrotron business. Not only the salary cut, or disguise Experiments head firing. But many that I have not dared to write because I was afraid of the personal consequences. And I still have my doubts to write it.


It's fun that the email sent to all staff say thanks to most of the stuff for the work well done. Not to all the staff, only for a subgroup. Perhaps this subgroup is the people that has been invited today in a farewell that has take place today in a meeting room with the window blinds down. 


After this vip farewell, some people who was there, explains that the candidate to new director have rejected the offer. But this is a rumor. Rumors... Alba lives in rumors we are not use to official announcements. The thing of that we had a new director candidate, is a rumor; the thing that there was a previous candidate who rejects the position some months a go, is a rumor; the thing that the management board doesn't have a meeting since 3 years, is a rumor. Do I have to continue? I feel really sad about how the things was done. But I still have the hope that the issue about our management will be fix, and we will be able to focus in usual problems (engineering, scientific,...) of one research facility.

New milestone reached: 200mA in the storage ring

Yesterday, 28 of November, about 19h local time, the storage ring of Alba have reached a new record in the accumulated beam: 200mA. (machine is design to work at 400 mA)

Photo of one of the screens in the Alba's place with the machine status

The head of the accelerators division have send an email to all the stuff in Alba, thanking all of us and saying that this is not only a success of Accelerators Division, it's a success of all the Alba's team and we like to share this milestone with all of us.

Photo taken the 26 of Nov, from the EC-JQK

This kind of small details contribute to the behaviour of the Alba's workers. Small things that made easy the live, and encourages to do more. It's the base of the workers the ones who are doing this. Even the dangers that one can find in the corridors.


Also I like to mention that yesterday I have reach one of my goals having a cycling of all the magnets of the storage ring with out any of them failing. I still have some problems with the setpoint on this power converters, but they are reduced from the 15% (when I have take the project) to the current 0'1% error rate. But I still like to reduce this to 0%. The device must be the last responsible to apply a setpoint. If the user tells the device, it has to insist until exhaust and it's not easy to leave a process exhaust.

Trend with all the storage ring magnets cycled

Alba's Call for Proposals for 2012 Beamtime Allocation

With an email to the AUSE mail list, I have receive the news about the Alba's user office: The call for proposals is open!


Now we are in commissioning and it goes very well and fast. We are reaching many goals each week. Afaik, at the beginning of next year we will have the friendly users: a very patient scientist who will do real experiments knowing that they are doing it in side the commissioning.

In the header of the Alba's user office, there is a tab labelled "call for proposals 2012". I cannot put a link to this due to a "season id", but I can snapshot it:

The only way to submit proposals will be this site of the user office. Create a user there is mandatory to be able to submit. Before that, is said that can be good to contact the scientist of the beamline if you have special requirements. I think this would be better to be included in the proposal and evaluated by who will have to develop it, to know who long is need to allocate this beamtime in a reasonable date.


The start-up of the beamlines will be gradual after Easter, but before come to Alba to do the experiment in the allocated beamtime, the user's must complain with the Safety Requirements:

It will be fun this thing about the exam, because after many years working where I never did an exam about Safety. He have received some trainings about Safety, but never checked the knowledge assimilated in this training.


We will see. If there is any reader who likes to come to Alba to do experiments, now it's time to do the paper work! Good luck!

Generalized Rijndael, an approach

Following the idea of the first post about a Generalized Rijndael, I have started an implementation with some constants of the standard implementations becomes variables.

An schematic for the Rijndael would be:

This operations uses a state matrix, it's the data structure who receives the transformations during the (de)cipher process. This state matrix, in the AES, contains words of 8 bits in a 4x4.

First of all the input (of 128 bits) is cut in this basic words of 8 bits:

There are two ways to modify the size of the input: change the size of the matrix or change the size of the word. Following the article Small Scale Variants of the AES, the two options to reduce the input size from 128 to 32 bits under a Rijndael model:

• Reduce the state matrix to 2x2 (in the AES is 4x4)
• Reduce the word size to 2 bits (in the AES is 8 bits)

But, what's the best way? And there is another question, how big would be the key?

In the AES there are 3 options: 128, 192, 256 bits:

This matrix will be the input of a keyExpansion() function to have the segments of this key to be used in each part of the rounds. 

Why this sizes? Like many of the times, the choice of this 3 sizes corresponds to standardisation reasons like set a small but enough number of them to choose. The original Rijndael supports much more options: you can set a key of 512 bits and structure it into 16 columns in the key matrix. Even 1024 bits key, with 32 columns, the key expanded will still be 44 elements if the number of rows and the number of rounds are still the same.

Furthermore, with a 128 bits block of plain text and key (matrix 4x4 and word size 8) there would be 40 rounds instead of 10. In this case the key expansion will have 164 elements instead of the 44 of the standard. (the number of elements in the key expansion is #columns*#rounds) 

But how to define this parameters in the good direction? Can be the number of rounds be less with in a safety way? Or can some day be necessary to increase this number?

The Rijndael have a good performance over 32 bit hardware. The word size of 8 bits together with the 4 rows who gives 32 bit operation in the ring: . But in deep, the most powerfull feature of the Rijndael from the computation point of view is that it works in the very basic and that means binary.

I hope I'll write soon answering this questions.

Generalization of Rijndael, an introduction

Long time a go I have received a request to prepare a system to encode some data in barcodes. I thought in two options: symmetric cryptography or hash algorithm. But, there where two requirements: "non collision (in between the same key)" and "recover information from the code". Then the choose is made, they can only complained by the symmetric algorithms.

The first symmetric algorithm was to simply operate with an xor operation. But this, as a Vernam type algorithm, is more to a stream ciphering or a one-time pad. Basically means is not the correct algorithm if a key is used more than one time.

To think in the block symmetric algorithms, the old DES, the new AES or any of the finalists in the trial are candidates. I have decided for the Rijndael, the winner of the AES contest. Usually the input/output size on the symmetric algorithms must be as big as possible because the data to cipher is much bigger. For example, in the implementations of the public key cryptosystems is usual to do a hybrid system, and the data is very big. Usually the problem on the symmetrics is to interlace the blocks to avoid patterns between them.

One of the goodness of the Rijndael is the capacity of extension, bigger of smaller. The state matrix, in the standard is 4x4, but the number of rows and columns can be changed. Even more, they can be different between them. The word size, is 8 bits (having operations in 32 bits because 8 bits * 4 elements in a column), but it's possible to do Rijndael with different word sizes.

In the application about I'm working the block size will be below 128 bits, but is not fix having the idea of 64 bits block size. DES is 64 bits block (54 bits effective key size). But why to use a replaced algorithm having the possibility to adapt the Rijndael? Even more, with Rijndael the key size can be also adapted to the needs. But in crypto, any modification must have a previous process of deep think, and a post-process of forever-think.

The Triple-DES was an extension to make bigger the key sizes like 112 or 168 (56 plus 2 or 3 of the simple-DES), and there is an extension for the AES with the name AESWrap (the rfc3394), what can be thing like a sextuple-AES.

There is a difference between DES and AES, and between Triple-DES and the AESWrap. The Rijndael is not only using the key, is also doing an expansion of this key to have more bits as a key. Furthermore, the AESWrap is doing a key derivation function to introduce more dispersion and confusion.

Lets go in the first step of this project: A Generalization of Rijndael to have the data block size parametrizable, also the key size and the number of rounds.

Lets start from the simplification, how to do an Small Rijndael Variant? I have found two articles very helpful on that task:

• Mini Advanced Encryption Standard (Mini-AES): A Testbed for Cryptanalysis (2002) by Raphael Chung-wei Phan
• Small Scale Variants of the AES (2005) by C. Cid , S. Murphy , M. J. B. Robshaw

One book for cryptography developers:

• Cryptography for Developers by Tom St. Denis

And the mandatory books for Rijndael:

• AES Proposal: Rijndael (v2) by Joan Daemen, Vincent Rijmen
• The Design of Rijndael AES - The Advanced Encryption Standard  by Joan Daemen, Vincent Rijmen

Alba Machine Status

Trying to get pagerank to the Alba's machine status, I like to mention that the beamline 4 is doing their best to start with the commissioning. It's the MSPD on the top left of this machine status and recently we have added the information about its insetion device:

All the 7 beamlines have opened the frontend and they have received their X-rays but this commissioning is ongoing. Some times we go faster than expected, sometimes we have unsolvable problems. But we are doing efforts to be faster than expected.

Next week, the machine will be shutdown to allow us to do some works in side the tunnel.

Galileo's one day (more) delay

I have work in the Galileo's Gstb-dsf project a long time a go. At that time, many times have said that Galileo was about to be launching satellites, but the Giove delays I understand that we should wait. I've been waiting for today during years and I can wait for one day more.

But I don't like to talk about this delays and the big amount of money that they would cost, apart to the cost of the system itself.

Don't wanna forget Glonass (Rusian) and the Compass project (Chinese-European) , but my knowledge is more about GPS and GNSS (Galileo). What's the difference between this two systems? All this satellite systems lives in the medium earth orbit (about 20000km from earth surface), how can they be different? The name says the difference: The Gps is a positioning system, and Galileo is made for navigation. Motion is the difference, and this difference is given by precision.

The mathematics behind it are the same in all this systems. But how this precision is given? By the time... Yes, the precision given by the location systems is given by how precise is the clock in the satellite and the information provided in the broadcast of the signal. Part of this signal can be emitted encrypted to only allow to certain users to access to the complete time stamp.

The other difference between gps and galileo is the orientation of the service. Gps is a military project from the US, because of that the main goal of the system is the availability for military applications, and the civilian service is a secondary thing. The precision of the system, then, depends of which type of user you are. But Galileo is civilian from scratch, even this doesn't mean open for every one.

Galileo will have an open access signal, accessible by every one like gps, with some better presision. But there will have some levels more:

• Commertial: Paying a price, the user will have the right for a controlled access for commercial applications who require more more than the basic, and a warranty on the service.
• Regulated: Paying another price, it's oriented to high security applications who cannot suffer interruption or distortion due to its security reasons.

Don't be to paranoid, the Regulated is thinking in civil aeronautics. Having the main improvement in the vertical precision and the 99% of availability warranted. I hope emergency location beacon systems will have access to Regulated by default, not having devices to some safety and some better, more expensive.

Update 20111021: liftoff!

starting the beamline commissioning

In the Alba synchotron we are reaching some goals day after day. During this last years we have started up the linac, the booster and, this year, the storage ring. Also, this year, we have opened the frontend in some beamlines. Starting in march with Mistral's beamline, and the first x-ray light in Alba (a bit before in the diagnostics beamline with visible light), we continue opening 4 of the 7 beamlines at the end of May.

Today is the day to start the beamlines commissioning. During the day there are some hour planed to have machine physics and some hours planed to delivery beam to the beamlines:

Step by step, with a low current in the storage, we are opening frontends.

(The machine status is not yet public, like it's usual, we have to be happy with snapshots).


Update @ 20111019:
I don't have an snapshot of the machine status with more frontends open, but it's a thing of opportunity: to be looking on this application in the correct moment.

Update @ 20111024: The machine status can be saw from out side. But not yet searchable from google or the "search" in the cells website.

Money doesn't exist

In the Tang dynasty, something starts changing. Since then the money starts to have another representation: the banknote. This, that have seen as an improvement because the traders doesn't need to carry the weight of the metal pieces. They has been able to travel in the empire with the possibility to exchange the paper into money based on metal. An at that time, the paper had a meaning in precious metal.

From that time to our days many times the "smart" leaders have realize how easy is to print more paper that the precious metal that they have.

The last time that this solution have set is a very big historical event in the richness of the world, it was when the US president Nixon breaks the direct conversion between the dollar and the gold. After that all the meaning of money is that it's something that can be exchanged for goods. It's only based in our trust on its value. At that time, the meaning of money have change.

Even worst, today we have one hack further: the electronic money. Now it's not necessary to have the banknotes in a safe who backup the e-cash. Like with the gold coverage brake, but worst. If previously was easier to print a paper than have a precious metal: have a couple of bits in a computer is even easier.

Why, with today's world crisis, the concept of the money have an even worst meaning? Apart of the problem with the meaning of the money, the concept of the debt is corrupted by the economics engineering. It doesn't have sense when I hear that Greece have cheat in the numbers many years a go helped by banks. The rating agencies are trying to clean their faces saying that now they are doing their task (not having everyone with the "excellent") but not assuming responsibilities in the subprimes and the huge collapse in 2008.

After this brake down in the (north-occidental) world, the IMF, have said to the involved democracies what they have to do. But the ones who applied they medecine are not in the path of solution, but the ones who did the opposite way are improving (iceland). Even that, the orders that this IMF are saying to the countries, for example about the retirement, it doesn't corresponds with what they do to itself.

Even forcing some of the PIGS to make changes on their constitution, Belgium have been in a political crisis on about 480 days without government. During this time their economy has been not enormously affected by the world crisis, far from that, their economy grew during this period of frozen budgets and laws. We may learn from the Belgium "solution".

The ECB also dictate its will to Italy and Spain (at minimum) to have their "service" or "protection". When the ECB is loaning cheap money to the banks, and this banks are loaning countries like Greece with a much bigger interest, the meaning of this institutions are loosing its meaning.

There is money to save and rescue the banks and don't left them abandoned to the markets. This new money can be new circulating money (like print more banknotes) or injecting money in soft credits to the banks (like creating bits of e-cash in a server). This to fix the banks' cheating, doubling money using the fractional reserve. That is, only a fraction of the deposits are "in the safe", there is a part that can be moved by the bank to produce more money. But then this money can be count in different ways, two, three or many times. The same money can be counter by me, by you, maybe by a third.

But the countries are left to its luck in the markets (where this banks play). There is no money for the social politics, we have lived out of our possibilities and we have to reduce the budget. But rescuing banks and paying enormous compensations to fire its executives who fails in its task. It's possible to "print" new e-cash to save the banks (with an inflation risk), but due to this risk this cannot be done for the countries.

But their big numbers are related with the normal people, who live normal lives. When they fail in economics, all of us suffers, but not them. Perhaps, they will have a headache because a crash in the market. But for the normal people this means a problem to eat during all the month. An this is not only headache, is also stomach ache...

In the Madrid's community, there is no money for the education. But the visit of the Catholic pope to this community cost more money than this cut. And this is only the community investment on this act, because many companies have "donate" money to this act in exchange on some fiscal benefits (due to that I have remembered the expulsion of the money-changers of Christ in the temple).

In Catalunya, even that in 2003 the gasoline have add a new tax called "sanitary cent". But further than a cent, it was a percentage corresponding to a cent on that year. Even that in 2008, Brussels say this tax is not legal, our politics refuses to remove it. This tax has been made to pay the sanitary bill, and they say is strictly necessary to avoid other less popular measures like the co-payment (you pay something "symbolic" every time that you visit the doctor). But now, 2011, they still talk about this co-payment and still say they don't have enough money to pay sanity service.

They never have enough! A solution for today is only an excuse. What they say today can be the opposite of what they will say tomorrow.

And in Catalunya there is another example of what I see as this economics engineering swindle. How can be possible that the debt of the Catalan government depends on the "column" where somebody puts the cost of a metro line of the Barcelona's city? This is a cost, an inversion, a money paid to the providers (and probably to be paid to the creditors). It doesn't have sense that the numbers can be "make-up" this level. It's unacceptable that in economics the result is fussy depending on how you did the numbers.

Now Portugal have cut the special payments for Christmas and summer. Back to Catalunya, the region government have said that their executives will not receive their Christmas payment this year. The news said that they will save 1.8M€ and the measure will affect about 350 persons. Easy 1'8M€ / 350px ~ 5000€/px: they are not in the media of salaries. Why there is no consequences to this "executives" when they fail in their task? But my doubt is which will be the workaround to pay them using another "ways"?

In the rescued banks (using "public" money) is even worst: the bank managers receive tones of money to be fired. If I do such a mistake like they did in my job, I'll be fired with out any payment, and probably with a lawsuit.

There are millions of persons unemployed in Spain (and the rest of the PIGS, and in the rest of the world). But locally it looks more like a lockout. Since 2008, many companies have instrumentalized this crisis for a cheapness firing the workers and reduce the salaries of the ones who "survive" to their burn. With this crisis, this country is only making big and deeper the bags of poverty. Making the social fracture much bigger. The ones that have more are have even more, the ones that have something are pushed together with the ones who already didn't have nothing before the crisis.

My conclusion is that the representation of the meaning of the richness has been lost. The hack of the banknotes and the mistake that is print more banknotes that the precious metal in the safe has go one step further: the mistake of generate more e-cash than the banknotes the supports this bits. The central banks are injecting this e-cash to big hole of the multiple-counting made by the banks, making this multi-count real or signed by this authorities (e-cash emission using bank soft credits). And to contain their hyperinflation, they force the final citizen to be push to the poorness cutting the social goodness and the menace of the unemployment.

The unemployed people doesn't have money to exchange for goods, but the ones who still have a jobs doesn't know for how long it is, and doesn't exchange their e-cash. This is what is avoiding an issue of removing the banknotes from the banks. The banks are being saved to maintain the confidence of the people in the e-cash. Because behind the e-cash, there is no banknotes, behind there is no precious metals, behind there is no richness.

Behind the capital and the speculation there is nothing. The production of goods is less productive in this society than generations of hacks to cover mistakes. This society is an imaginary giant made by real feed of mud.

Dennis Ritchie

A few days a go, a Very Important Person in the computers world have died. Even that the news has been talk only about an Important Person, and many people can think the Steve Jobs have made a revolution in computers, Dennis Ritchie, in my opinion, have more important goals to receive the "very" in the vip status.


Without his work on Unix (and previously on Multics) together with Ken Thompson and Brian Kerninghan, the Mac operation system wouldn't be possible. Yes it's true that Mac have had many good ideas on usability, but it has many lines written in C, a high level programming language designed by Ritchie and the contribution, again, of Kerninghan. Almost all the computer scientist have on mind Kernighan&Ritchie, and the ones who doesn't probably have problem.

Cycling magnets

Since I've been in charge of the control of the power supplies of Alba synchrotron, I have discover many new things. After more than four years an absolute new world is in front of me.


One special thing that we do with the magnets is to cycle them. But what does this mean?


The magnet hysteresis is the reason of this procedure: the magnetic field produced by an electromagnet is function of the current applied by the power converter, but it has a path dependency. Or is not the same to arrive to one position if you come from different places. Also it have dependency on the length of the magnet but this is constant, at least in our ones.


From a very simplistic view, what I understand about this is a graphic like:

Where to arrive to one position on the green line, for example 0.95T you have to set a current of  480A (assuming a magnet of 1m to simplify, and all the numbers are my inventions). But depending from where you arrive to this current you will be on one of the black lines. Then you will have a magnetic field between 0.89T and 0.98T, but not exactly what you want.


The solution is to cycle the magnet, this means, from the current where you know the green line for the magnetic field you want do a procedure to the maximum current to the minimum and to the maximum again to run in the red line. Do it again and you will be in the green line to finally go the the setpoint and you have the expected magnetic filed.


The procedure it's easy: setpoint-max-min-max-min-max-setpoint. But how to make this automatic?

Cycling of all the storage ring magnets (with the new approach)

The first approach we did was using the Sardana Control User Environment. A very abstract view of a magnets can be like a motor: you have many positions not in distance unit (meters, millimeters  microns,...) , but in current unit (Amperes) of the electromagnet.


This has been working well for a long time. The users can do this procedure in a automatic way, but the read back of the power converters some times is a bad player.


The approach using a macro have some implications and a collateral damage. A macro is launched and the MacroServer is the device in charge to run this together. All the magnets selected by the user have a controller in a Pool of motors, and the MacroServer is able to coordinate motors from many different Pools. This pool motor controller is the one who bridges the communication to the power a supply device server offering a interface to the upper layers.


The issues appears when the device of the power converter shows glitch on the current read back. Is not a thing that changes the magnetic field, but is a thing that changes the state of the device to moving. The controller is propagating this to the pool.


If due to any casual planet alignment the pool receives the move command, during a glitch it trigger an exception because it can not distinguish the glitch to a real movement commanded from somewhere else. This has a very small probability, but if you add enough magnets this can happen more often. And if you add that when this happens, the cycling of all the other magnets is cancelled the cycling would be restarted and is possible that next time another magnet has a glitch.


How this can be fix? Who has the responsible to cycle the magnets in the old solution? The macro. But it has some problems with the bad guys of the magnets. Even if we mask this glitch behavior (thing that we did), the main design issue is that a problem of one participant, disturbs all the others. Sardana needs this feature because it is a feature need for coordinated movements.


The new approach:
Each magnet  is responsible of itself.


Further than coordinate the cycling, why not make each magnet (the tango device of the power supply) responsible of itself cycling?


Introducing a command to the device we have what was the macro in side of this power converter control. A problem in one magnet will only affect this magnet. All the others will continue their procedures. If the operator saw something in one of the magnets can abort the cycling of this one, letting the others cycling.


In the second image of this post, of a taurustrend, with the cycling of the storage ring magnets is possible to see that the quadrupoles and sextupoles are independent to the bending. They have a smaller current range for cycling, and they finish early. Even more, if you look the quadrupoles and sextupoles, they are accumulating a shift during this cycle, and the ones with a smaller range finishes a bit early that the others.

Cycling the booster to storage transferline

More evident can be in the booster to storage transferline. The correctors, with a range of [-5A,5A] finishes about a minute before than the other big magnets. And between the other big magnets, here they have different currents and show this shifting better.


The result on the real hardware test of last Friday was succeed (also testing many abort cases) for Hazemeyer storage ring power supplies and for the Bruker linac to booster and booster to storage transferlines power supplies.


As far as I know, we reduce a procedure that can take very long by hand to a 4 minutes automatic process. That is an example of what the controls section tries to do: make scientist "lives" easier to allow them to focus in what they like, do research, do science.


Update 20110907: As usual, asking you get more info. Why this cycling procedure is working? It's not, like I said a max-min iteration: it's a sinusoidal function approach. Due to the ramp (speed of the current motion in Amperes per second) and the acceleration and deceleration close to the setpoint this procedure does somenthing quite similar to a sinusoidal function and give this property to fix the hysteresis.

Brookhaven National Laboratory: NSLS

This summer in Alba we have received a visit of a scientist of the NSLS-II, and he did a seminar about this machine under construction.

They have a background on synchrotrons. The have a machine close to the 30th anniversary, the NSLS-I. It is one of the firsts 2nd generation synchrotrons, and it have to very different submachines the VUV (with the 30th aniversary in 2012), and the Xray (30 years in 2014).

NSLS-I layout

The seminar was about the their new beamlines in the NSLS-II project, but reading about this machine with two storages rings opens my curiosity.

The machine status gui must have some peculiarities; or to have some of this guis. From the point of view that can be saw as one machine, there is one machine status.

Different beam energies, different accumulated currents and different live times. Very different behaviors of this to storage rings. The availability of the beam for x-ray ring is longer than 10 hours but the refilling time looks to be about an hour, then this seems to be a limit for a time resolution experiment. The ring for vuv have much smaller live time, 3 hour, but the refilling looks fast.

From my poor acknowledge (almost null) it's weird that the vuv, with more current have an easier refilling. Probably more boosted beams are need to accumulate, but it's a less energetic beam.

Living the commissioning of Alba, I don't wanna imagine how can be a commissioning of a booster with different rampings of the magnets depending on the destination storage ring. Also the radio frequency must be different. It looks to be like two completely different commissionings for the same booster.

Spanish constitution

This august, and in a urgent way, spanish parliament has started a modification of the Spanish constitution. Like al the laws they can be changed, but the answer to any request to modify this constitution has been always "NO".


Spain is a monarchy. During the lasts years we have had the discussion in the media and between the politicians and the pro-monoarchy  about the convenience to modify this constitution for better equality of generate. What that means?


From the child of the king of Spain, the women can only inherit if no men has born. Than means if they have 7 child and the 7th is a boy, the previous 6 women will not be queen (even if they are better or not).


But after a long time says that is not easy to modify the constitution, because this request 2/3 of the parliament and a dissolution of it self after the modification and a referendum... This time the modification can be done without the plebs referendum and very very fast: in less than a month...


The issue of this modification is more than what the media-news says. Is not only a thing of the top on the debt, is not the issue of not ask the "demos" of this "democracy", in my opinion is the introduction of a sentence: "135.3 (...)y su pago gozará de prioridad absoluta.(...)" (and its payment will have absolute priority).


I'm not an economist, but more than a modification to avoid a too big debt, it's a modification to avoid to follow the way of Iceland. I think that because also "135.4 Los límites de déficit estructural y de volumen de deuda pública sólo podrán superarse en caso de catástrofes naturales, recesión económica o situaciones de emergencia extraordinaria que escapen al control del Estado (...)" (this debt limits can be exceeded in some cases, one is an economic crisis, like we have now). This don't fix the current "problem" of the debt, because there is an exception for a case like where we are. One of the things that fixes is to make unconstitutional the Iceland solution.


Update: It looks like the Iceland solution have had better results than Ireland's. Just the countries who follows the rules of the IMF, the ECB and the rest of experts, are still in crisis with out symptoms of recovery.

PyTango in Ubuntu natty

I have installed the lastest relase of kubuntu in a new computer and there is a better newer way to have tango installed in your system than the guide for tango that I have posted


Tango has been released for 10.04 LTS distribution of ubuntu by one of the developers: Alessio Igor Bogani, worker in Trieste's synchrotron: Elettra. After that the idea have had succeed and we have a official repository for core of tango.


Then: I had s pending to publish a how to for this repository and mark the old one saying that here is this update. Well go ahead.


step 0: Remove older tango-cs packages
If you have installed this abogani's repository, is better if you remove its packages and then remove the file in the '/etc/apt/sources.list.d/abogani-tango-.list'.


$ sudo add-apt-repository ppa:tango-controls/core
This also adds for you the key of this repository in your keyring and the file 'tango-controls-core-.list' file.


Like in the abogani's way here there are two ways to continue: with or without tango-db. The second way assumes that there is another server with the tango database running.


step 1, option with db:
If mysql is not installed in the system do it. I am not sure if this works well being executed in the same apt command. I suggest to first install mysql and then tango:
$ sudo apt-get install mysql-server
$ sudo apt-get install tango-common tango-db tango-starter tango-test python-pytango libtango7-doc omninotify
This also installs the necessary dependencies.


step 1, option without db:
The list of packages to install is the same but without the tango-db package:

$ sudo apt-get install tango-common tango-starter tango-test python-pytango libtango7-doc omninotify

step 2, starter is running in your system:
Check is there are running processes from the new user 'tango'. For example, 
$ ps -ef |grep tango
Should show two process: the DataBaseds (the one who listen the port 10000) and the Starter (the one responsible to launch the device servers on start up in the correct sequence).


Also, another way to check that this works fine, is to try to "import PyTango" in a python interpreter.


I hope soon I will explain how to configure some devices to simulate things of a synchrotron machine. But before we will have to prepare and configure the tango core utilities.