LIFE IN VSSC
Hello my dear friends. I recently completed our PS-1 program successfully from Vikram Sarabhai Space Centre, Thiruvananthapuram, studying and recommending various Fault Tolerant Hardware and Software to be used for the Manned Space Mission scheduled to be undertaken in the year 2011.
One unique feature of our otherwise unique PS program is to maintain a PS diary in which you have to record everything which you did there. Perfect instrument to vent your frustration as I found it out.
Well, my friends asked me to create a blog out of my PS diary as they were apparently pretty interested in reading what I wrote in it. It might become a bit long for everybody so I will present it in small pieces.
Hope you all will enjoy (or not!!!). In any case, please let me know by your precious comments.
Day 1 – PS1 Begins
We were staying in the Aruppe Bhawan of St. Xaviers College, Thumba. In the morning, after waiting for some twenty minutes for a bus outside the college main gate, we got into one and reached VSSC by 10 am. There we were introduced to our PS instructor, Mr. A. Amalin Prince, Lecturer, EEE Group, BITS – Goa. From the gate of the Veli Research Centre (VRC), we reached the Public Relations Office (PRO), where we were supplied with entry passes of one month’s validity. After a security check, where all storage and electronic devices, including calculators, were taken away from us, we went to the Human Resource Development Division (HRDD) Lecture Hall. We were divided into three groups, EEE, Computer Science and RSR Development groups, I being in the first group with Anant Gupta (DADA), Deepu (Sleepu), Jithin Parayil Thomas and Saniya Deshpande. We filled a list where we were to give our contact information and then we were taken to our Project Director, Smt. Valsa B., Head, Quality Division Flight Software (QDFS). She led us to room number 703 which was the Software Verification and Validation Lab (SVVL) where we had to do our project, the details of which were to be told to us by Mr. Anil Abraham Samuel (Scientist, QDFS). Our project had something to do with flight control hardware design. For the first three or four days, we were to study the techniques used by NASA, ESA, CNSA and RSA for their launches and we were supposed to suggest some means to enhance our own launches.
Something big is really waiting to happen, with the Tricolour, proudly flying high, looking down to us to perform.
Day 2 – Target Set
We reached on time to our destination – Room no. 703 (SVVL) and met Mr. Anil Abraham, who was to guide us through the rest of our PS. He started off with the basic control system of the PSLV and the GSLV and then quickly switched over to new generation control system for the manned space mission of our nation. In the already existing configuration, we used dual redundancy, and every part of the system has its own backup for safety. It uses the bus topology made up of the MIL – STD 1553B bus, which is a Military Standard bus developed by SAE in 1978 and is still used in the space missions of many nations. Each subsystem has two identical boxes, the prime and the redundant parts which work simultaneously giving rise to Hot Redundancy so that if one fails, the control is taken up by the other immediately. The main computer(s) controlling the navigation are the Navigation Guidance Control Program (NGCP).
Day 5 – Nothing to do!!!
Today is Monday. We reached our centre on time. Our work, as of now, was to be done in the library as we were to study different redundancy aspects utilized by different space agencies for their manned space missions as also the fault tolerance and display techniques for the human in the spacecraft. But for that, we needed the Library pass for which the HRDD applied today and which, we would be getting tomorrow. Meanwhile we were given some papers on Error Handling by Mr. Anil Abraham to study which we did for quite a long time and had many discussions and debates on it. Since nothing else was left to do, Mr. Anil let us go.
Day 6 – First day in VSSC Library
We were told by the HRDD people that we could get into the library as there was nothing as such to be called the Library Pass. We went to the library and quickly searched for some books and reports on topics such as redundancy in human space flight, avionics of space shuttle, fault tolerance in on – board equipments and display techniques. I for instance got one book on Military Avionics in which I got some idea about the display techniques used by them. There was the Head Up Display (HUD) in which the TV image is projected onto the windscreen for targeting by different reflective and refractive techniques.
Day 7 – Microfiche
Second day in the library. I searched extensively for reports on topics like redundancy and display from the intranet. The library is arranged not in floors but in half floors or mezzanines. We have ground floor, ground mezzanine, first floor, first mezzanine etc. I came across the Microfiche which were kept in the second mezzanine. These are thin film strips of the size of a postcard on which about 40 pages of written or typed material is visually stored which are then magnified on a screen by a special reader to make them legible. I was studying redundancy in the Voyager spacecrafts. Those 40 pages were of the size of a half chart and the font size was that used in a book, or for that matter, used here. The document was 16 pages long and the library caretakers joked that I can take my own sweet time (2 to 3 days!!!) to read it fully.
Well!!! Hoping that I don’t have to continue with those microfiche tomorrow.
Day 8 – Typical BITSian Life Revisited
If you are a BITSian, then there is no way you are going to feel lonely. Continuous evaluation is always there, as your most faithful friend, soothing you in times of distress and pouring cold water in winter and hot water in summer on your happiness, giving you an overdose of nothing but itself. I went to the HRDD Lecture Hall, gave the test, got 3.33 out of 5 and came back to meet Mr. Anil to report to him what exactly we had done. Then we went to the library as usual. My groupies were reading books on military avionics, aircraft display, space shuttles and I was desperately searching for a good book on redundancy. Call it my luck; I came across Encyclopedia Britannica, my favorite!! I relished reading them, especially the accounts of historical characters like Cyrus The Great, Darius The Great, Alexander The Great, Chandragupta Maurya, Asoka The Great, Bahram Gur, Alcibiades, Akbar The Great, Saladin and the likes. That I knew already knew much more than what was written in them is another matter altogether!!! Oh! I forgot to mention Ashurbanipal!!!!
Day 9 – At last… One useful book
Today was an uneventful day. But the silver lining was, I found out a handbook on Computer Science. I hoped to get some useful information to be kept in consideration while designing a microprocessor specifically for a space shuttle, something of the sort Mr. Anil was talking about. I read about speed considerations, register allocation for programs and a small debate sort of thing on what decides whether a microprocessor is 16 – bit or 32 – bit or something else. There was nothing interesting as such and I quickly dozed off woken up by Jithin as he had to catch his train.
Day 12 – Another Uneventful Day…
We were not getting enough materials in the library. Not because there was a lack as such but because the Digital Search Engine was not efficient enough and searching through the five tiers of voluminous information contained in thousands of books easily discouraged anybody. And certainly not the Microfiche!!! I continued with the Computer Science Handbook and got some further information regarding microprocessor architecture. After coming back from the VRC, we studied the print outs of avionics which Mr. Anil gave us.
Day 13 – Kuber Ka Khazanaaaaaaaa……..
At last, we got it. Access to the internet in an ultra secure place like VSSC where even the office staff has restrictions on using it. And we were the prized possessors of a much coveted commodity which is available for 24 hrs in BITS but which, here in Thumba or Veli, was a scarcity. At once, information seemed to pour down on us like the monsoons of Kerala. In one day, we collected four times the information we collected from the library by searching manually for some ten odd days. And all this, because Mr. Anil got us the permission to surf the net. For the first day, we pounded upon the display systems and got papers related to Glass Cockpit Display and yes, the Active Matrix Liquid Crystal Display (AMLCD).
Day 14 – Fishermen and their NET
The collection continued. We moved our attention to the microprocessor. Initially NASA used the old IBM AP-101 processors in their shuttles with Triple Modular Redundancy (TMR) in each computer. The ESA people had developed their own range of microprocessors based on the open architecture of SPARC (Scalable Processor ARChitecture). The latest in this series is the LEON3-FT processors which is internally fault tolerant and is also radiation hardened so that it is not affected by the cosmic rays. ESA is also planning a quad – core processor based on the LEON3 model which will be called the GINA (Giga INstructions Architecture). NASA is also bending towards multi core processors and adding a bit of redundancy to it so that if one core fails, the other core quickly takes up its work and the processor carries on with a graceful degradation of performance. A multi core architecture will consume lesser power than a multi processor one.
Day 16 – A Time to Recommend
No, you are not wrong. There were no Saturday or Sunday and yet a day is missing. This is because the Left Democratic Front (LDF) had called a hartal in a Left dominated state and not even private vehicles were allowed to ply on the road. We started to prepare a report recommending what can be the possible redundancy scheme to be used in the on – board computer system of ISROs manned space mission. I worked the whole night on the microprocessor part and completed it at 5.30 am!!! Then I went to sleep, only to be awakened by a curiously irritating phone call in which the caller kept on asking “redundantly”, when I was going back to Pilani. I could not sleep and at VSSC I was drooling and had a severe headache. Meanwhile, we found out different data bus protocols, safer and more efficient than the MIL-STD 1553B, and had started final shape to our report.
Day 19 – Citizens of Democracy
Indian Constitution gives everybody a chance to speak. But people should also know the etiquettes of speaking. And so, Group Discussions (GDs) are a tool to develop your expertise in that area.
We went to the HRDD Lecture Hall and to our surprise, were suddenly a part of a lecture series on the rocket propulsion system, which was originally designed for some outside NIT students, and which, we too were asked to attend diligently. Everything was based on Thermodynamics and I have been desperately trying to get rid of that dreaded subject (remember ThermoD, Mechanical Technology…)! After the lecture we had our GD in which Mayank Jog kept on thundering some technical details which contained just heavy words and very little details and others including me were left guessing what those details were.
Definitely, I don’t want to know how much I got in it!!!
Day 20 – Another Lecture in the Queue
So again, we came to the HRDD Lecture Hall for the lecture and we certainly did not like the fact that we have to do the same thing tomorrow only for a good feedback. The lecturer started with the combustion engine and at once the memory of Mechanical Technology classes came to my mind. My brain got fused and all the diagrams which he was showing were curiously similar creating a big mass of hotch potch in my mind. I am in no position to tell what happened after we came out of the hall.
Day 21 – Oh No!!! Not Again!!!
I decided not to go to the lecture today but at the insistence of some of my friends, I decided to go to the HRDD hall. I stayed there till the first break without even getting an air of what was being taught. I just remember some Tsiolkovsky Equation (I remember it by its strange name) which the NIT guys seemed to be particularly familiar with. After the first break, I came out, ate some snacks, and went to the library. After lunch we went to Mr. Anil who gave us our schedule of work, according to which, we would be in a great need of internet resources and have to submit a report every 4 or 5 days.
Day 22 – Got Rid of It!!!
Whatever might befall, today most definitely I was not going to the lecture to kill my time aimlessly. I wanted to do something productive now that we have got our work schedule. So almost all of us went to the library and I got a wonderful book which had something like integrating an Assembly Code with a C Program. Then I went to the internet where I frantically searched for SPARC microprocessor and it’s Instruction Set Architecture. I also found out some papers regarding Intel’s Pentium and Multi-core processors’ instruction set.
I am definitely going to study the instruction set and the data bus architecture.
Day 23 – A Long Wait!!!
Today was a day to wait. Only to get our entry passes for another one month. The HRDD was taking its own sweet time to forward some letter to the Public Relation Office regarding our passes and we were waiting in the Lecture Hall. After having our lunch we waited in the PRO for some time and after getting our passes, since the time was already over and chances of meeting Mr. Anil after lunch are always bleak, we went back to our hostel. Nothing productive was done today of course and we were definitely feeling the pinch of it since we were already impeded by the lecture series this week.
Day 26 – When Roles Get Swapped
Today it was our turn to play the role of a teacher. It was Seminar 1 and our EEE group presented the topic “A Brief Overview of the Organizational Structure of VSSC and an Introduction to the New Generation NGCP systems used in the Indian Space Missions”. The topic was introduced by Deepu and Saniya followed explaining the different levels of management at VSSC, the various achievements attained in the field of space technology. Anant and Jithin continued with the present NGCP configuration, explaining concepts like redundancy management, reliability, fault tolerance etc. I concluded with a brief description of various processor architectures such as SPARC V8, LEON 3FT and the ones developed at the VSSC itself, Vikram 1601.
Day 27 – What Are EEEites Doing With Software Engineering???
We met Mr. Anil in the morning as usual. Now as per the handout given by him, we are working on the various software components used in the launch vehicles such as NGC software, Integrated Vehicle Health Management (IVHM) software, on – board checkout and the use of open source OS in time triggered task scheduling. I took upon myself the OS part. Since we haven’t learnt anything about software engineering, he told us he would give a brief introduction to the field tomorrow and explain the basic concepts such as life cycle of software, its various stages etc. In the afternoon we found one IVHM software called Livingstone2 written in C++ for both Windows and Linux environments.
Day 28 – Thank God that I am a C6ite!!!
As was told yesterday, Mr. Anil gave us an introduction to software engineering. He also gave us a copy of a book on the same topic written by Roger Pressman. He explained the life cycle of software in detail. It includes various stages such as requirement specification, design, development, testing etc. He also showed us the differences between similar sounding terms like verification and validation. He also mentioned the different models used in software development such as waterfall model, spiral model, prototyping (“iterative” as well as “throw away”) etc.
Day 29 – HARD Realities of SOFTware
Mr. Anil continued with the various features desirable in the design of software. These include modularity, reusability, cohesion, portability, less coupling etc. (Now please don’t ask me their meaning!!!). There is something like an ideal software design has more cohesion and less coupling. He also told us about various kinds of software testing – Black Box, White Box and Grey Box testing…
Day 30 – A Day to SURF!!!
Today me and Jithin browsed the internet to find out more about IVHM and NGC software. IVHM is used to monitor the vehicle health constantly, report deviations and automatically rectify errors. Regarding NGC, we found out a paper about PASS (Primary Avionics System Software). It was the software used in redundant set of computers in the US Space Shuttles. We also found some papers relating to the implementation of time triggering in Linux.
Day 33 – Untamed Fascination
As I told earlier, for our next report, I took the whole part of Operating Systems upon myself. The topic was to estimate the possibility of using the Open Source Software like Linux (RT flavor), GNU compiler etc. for realizing the software and come up with new ideas and their feasibility of getting implemented. Soon after I started working on that I realized that I should have tamed my fascination with Linux, linking COFF files with object files of C codes using the GNU C Compiler, integrating Assembly code with GNU C code and other things. I know absolutely nothing about the working of the Operating Systems, processes and threads and so desperately went to Mr. Anil for help. He explained some basic concepts to me which would surely help me in my Operating Systems course next sem. He also suggested me to read some post – graduate level books on Operating Systems.
Day 34 – Even Trains have Stoppages
For a normal BITSian, tests and quizzes should not matter at all, we are so used to it. But somehow I feel that they are now acting as an impediment to our normal work. We were going so smoothly for our next report and I was getting lots and lots of material regarding Real Time Middleware in Windows XP/CE or for that matter, in Linux. And suddenly everything came to a grinding halt. All because of a 5 marks quiz. I simply wrote whatever I thought would be appropriate. Oh!!! Did I really think about the quiz questions? All this while, the only thing that was running in my mind was TMOSM and the 520 General Purpose Registers (GPRs) in SPARC. I don’t even remember a single question of that quiz!!!
Day 35 – Context Switching
I spent the whole day working on Operating Systems. I had to study processes, scheduling, context switching, threads, monolith kernel, microkernel, virtual machines and what not. If at all I get any feedback form regarding how to make PS1 better, I would definitely suggest introducing some CDCs in the 2nd year instead of POE, Mechanical Technology and DySoc. If we are given work or project, be it even study oriented, we are handicapped for not having even the basic knowledge. Nobody likes being asked what they have done till their 2nd year and that too in a taunting manner. Thank God that I did MuP so I am able to understand SPARC architecture. Otherwise other C6ites complain about the bad handling of the course, Digital Electronics and Microprocessors.
Day 36 – I need… A Break…
TMOSM has started getting on to me. Its full form is Time – triggered Message – triggered Object Support Middleware. It lies between application program and the OS kernel. It’s an object written in C++. Application programs don’t directly access the kernel. They first access the TMOSM, whose Main Layer has a scheduler which runs at the highest priority over and above all other processes and threads, even if they are of system programs or application programs. This scheduler will assign time slots to all processes and threads. Then the second layer of the TMOSM, the Kernel Abstraction Layer (KAL) provides APIs for using kernel services by making system calls. No new language needs to be created. Only some libraries need to be added to the existing compilers for the TMOSM APIs.
Day 37 40 – My Battery is Battered Down!!!
Although Friday was a day of strikes and we could not go to VSSC, it was not a day to rest. We had to complete our report and many left that night leaving the whole work of completing what was assigned to others, besides my own dear TMOSM, on my shoulders. I did that and was totally exhausted today. Those who left, went to Periyar, and after coming back, did not show good signs. Deepu looked devastated, Saniya was down with fever, and Anant was grappling after being sucked badly by 5 or 6 leeches. We discussed our topics with Mr. Anil and came back.
Oops!!! What has gone wrong with me? I fumbled with the day. Its day 40 not day 37!!!
Day 41 – Exhausted of Good Headings
Today we again found ourselves surfing the net. We were to search for DO-178B as well as for checkout systems for not only spacecraft but also for launch vehicle and the crew module. We got so many papers and some seemed to have been prepared during the Stone Age or the Jurassic Period (I know that it is a big PJ!!!), they were so old. After sometime, others went to have lunch and I alone was surfing. As asked Mr. Anil, I was searching for Real Time Algorithms to be implemented on Linux. I found out many real time OS like LynxOS, VxWorks, eCos, RTLinux among others. I found out patches of RTLinux (18.2 MB) and its full source code (2.5 MB). Well! I already have the full source code for normal Linux for the Linux From Scratch (LFS) tutorial. I am sure I will enjoy!!!
Day 42 – Life going like a Local Train
Why doesn’t life give you an opportunity to complete your work smoothly? Why are there halts, stoppages and red signals every other day? What I mean by this is our second group discussion. I acknowledge the importance of GDs in professional life, but it is in human nature to complain and grumble when the smooth flow of their life is interrupted. And I am just following that, for I need to vent some of my frustrations that have accumulated over the past 6-7 years. I dare anyone who can tell that I have lost my cool on any occasion.
Well our topic was “should a developing nation like India invest in space research”. Frankly speaking, even though I am aware of India’s problems, being myself from a semi – rural background, I think it is a matter of national pride and self reliance and we should not debate over it.
Day 43 – Tanashahi Nahi Chalegi!!!
This is a typical slogan in Bihar politics, particularly when there is any Hartal sort of thing going on. Yes, I am talking about the one we witnessed, or should I say, I witnessed, in Kerala. I decided that whatever may befall upon me, I am going to VSSC. My only hope was the convoy of VSSC buses which comes to the bus stand near railway station during hartals at 9 a.m. From 8 till 10.15, I waited for them at the bus stop. The convoy did not come on that day and so I decided to have food. Oh my God! The streets were deserted, each and every shop closed down and police were roaming everywhere! Since buses were not running, I was stranded, 8 kms away from our house and that too near 12 noon with no signs of rain whatsoever. And all happened due to a hartal in which just 20 people took out a procession flanked by police ahead and behind so that “they” don’t cause any harm. Wonder what happens when a hartal is being called in Bihar.
I wrote about this hartal only because I witnessed it while others were lounging in there houses.
Day 44 – Another Day to Search
The whole day we kept looking for Mr. Anil. We mean only me and Jithin. Anant was preparing the part concerning programming languages and I absolutely don’t know anything what Deepu and Saniya were doing. Me and Jithin started looking for redundancy algorithms and a software certification standard, DO-178B. It is a stringent set of guidelines which has to be kept in mind in coding aviation software and which has little to do with coding and lots to do with project management and software engineering. The huge details, kept in an unorganized form makes life miserable for the one who tries to read it.
You will definitely not enjoy going through it.
Day 47 – Beginning of the End
The rough draft of our final report was finally beginning to take shape. Last night, I sat down and completed the study of DO-178B certification standards and also completed the part on the libraries of display software which was to be done by some other fellow but which, due to sheer neglect, fell upon me. I tried to raise the issue but it didn’t help with people who just want to snore away the time given to them. The compilation of the report was almost complete but Jithin said that he has done some more work on TTP/C communication protocol and so wanted to add something more to the report. Even I worked out some extra details regarding internal redundancy in processors.
Day 48 – When are we going to submit our Report???
Mr. Anil’s first question to us – What about the report? Should we tell him that the feeling of procrastination on part of some of us is delaying the work of the whole group? I and Jithin were the ones who had to face the question and I personally felt bad because such a nice guy is forced to keep so much patience. He was not annoyed but it was clear that he was a bit frustrated. Anant was doing his work in the library and the other two were missing since the morning and I absolutely don’t have any idea where they were.
Day 49 – I need to hold the reins
Now it was too late. We were 5 days behind our schedule. Yesterday after calling out everyone and giving them a stern instruction to read “Software Engineering” e-book which I mailed to them, everyone was present in the lab. We told Mr. Anil to just wait for a few hours before we could mail the final report to him. The reason behind this was Jithin, Anant and Saniya had to add some more matters which they studied. Mr. Anil taught us how to draw control flow graphs and how to verify the various procedures of avionics software written in ADA. Anant told me that he will sit for testing and mail his part to me. I somehow got into a café at night and submitted the full report only to get drenched due to heavy rain while coming back to home at 10 o’ clock.
Day 50 – The clock is ticking
Mr. Anil was happy that we had submitted our report. I was the first one to reach VSSC and I straight went to invite Mrs. B. Valsa, our project director, to attend our seminar. She told that she will be free tomorrow only after 11 am. The whole day Mr. Anil was busy with meetings and we also needed to make our presentation for tomorrows’ seminar. So he let us go early.
Surely, the clock is ticking for the final show.
Day 51 – The clock went on ticking
We were so skeptical about our seminar. Everyone thought that he or she might not even be able to speak for 5 minutes. Surprisingly, Saniya spoke for half an hour. I came and completed my part and was soon the centre of sentences like “time never seemed to move”, “you took more than 45 minutes”, “and we were thinking when you were going to stop” and the likes. I have a skin thick enough to ignore them. Jithin completed in another half an hour, Deepu danced out his part in 15 minutes and Anant had to really rush through his part as time was really running out.
Day 54 – Who says PS1 is Lite???
I wanted to come here much earlier but due to my usual bad luck, I missed two buses pretty closely and so just managed to come here at the usual time. I met Valsa Ma’am and explained to her how, due to unavoidable circumstances arising from the cancellation of our return journey train just five days before the scheduled date due to heavy flooding, we got engaged in finding out alternate routes and how our 2 days train journey has expanded into a 4 days one and so we couldn’t complete the report on time. She apparently was not worried about the report as the main work was already done. After that, we had to fill a strange feedback form from BITS which had more than 100 questions. Who is going to go through them back in Pilani is something to wonder!!!
Day 55 – The End…
In the VRC, on a big flat panel display, everyday a new Hindi word, along with its Malayalam and English equivalent are shown. Yesterday it showed “Farewell”. Strangely enough, it had come at a perfect time. Yes it was a coincidence but sometimes you passionately want to explain the unexplained. I don’t want to waste my imagination on this because of the obvious explanation that would come out of it. And that, of course, won’t be true.
What should I write now? That I met Valsa Ma’am and Mr. Anil to say that we had submitted our full report and now I am going to get my PS diary checked?
One story is going to finish. Tomorrow, we will not be here around. But I am definitely going to miss the cute, white pussy cat at the private canteen in the VRC.
The Tricolour is flying high, and I guess, we have done something worthwhile under its gaze.
