Tuesday, January 23, 2007
Zen and the art of hairdressing
I came across this nondescript establishment in one of my routine jaunts around the Daejeon downtown area. I have never seen a more succinct expression for the possibly difficult art of hairdressing. It almost sounded Zen in its depth. I shall leave it to you to ponder about it further.
Friday, January 19, 2007
Of Humanoid robots and your Golden ball
Readers be warned, this could end up as a deadly dull essay on a term project i did recently, and which i shall be presenting shortly to my lab. If your sufficiently bored with life to be interested in this kind of thing, please proceed right ahead.
I did this fancy project for my Introduction to Robotics:MEA453 course (Yes, I did introduction to robotics in my penultimate semester of a Masters in Electrical Engineering -with a Robotics specialisation and, no, i really didnt score that well, goes to show how much I really know in robotics). Anyways, it seemed like an out-of-world idea at that time, about 3 months back, but this error has been kindly corrected by my senior who told me such stuff has been in existance for ages now, in the field of humanoid robotics, its just that we dont use it on our pretty little bot.
The basic idea maybe be summarised as thus. Most of our walking can be explained simply by a big swinging ball on a stick. our body when on one foot pretty much behaves like whats given the fancy name of 3D Linear Inverted Pendulum which looks a bit like this:
I did this fancy project for my Introduction to Robotics:MEA453 course (Yes, I did introduction to robotics in my penultimate semester of a Masters in Electrical Engineering -with a Robotics specialisation and, no, i really didnt score that well, goes to show how much I really know in robotics). Anyways, it seemed like an out-of-world idea at that time, about 3 months back, but this error has been kindly corrected by my senior who told me such stuff has been in existance for ages now, in the field of humanoid robotics, its just that we dont use it on our pretty little bot.
The basic idea maybe be summarised as thus. Most of our walking can be explained simply by a big swinging ball on a stick. our body when on one foot pretty much behaves like whats given the fancy name of 3D Linear Inverted Pendulum which looks a bit like this:
We walk by falling. We fall like the shiny golden ball mounted on a stick. Our legs together act like the stick.I must admit, life seems a bit contorted when you think of yourself as a shiny golden ball though. The ball is our center of mass. Playing around with forces and momments acting on this ball pretty much explains everything we see such as Shakira's or Sreesanth's booty shake, the Elvis Pelvis, to my own fluid dance moves (really!). Now the thing with robots is , we like to pretend that this center of mass is stuck inside the pelvis. This makes thinks really simple to calculate, and in no time of approximately 4 years, we can get our l'il robot Hansaram (literally 'one korean guy' - I didnt name it so dont ask) start walking dancing and waving to kids, while we are talking to the pretty ladies nearby. Now I dont know too much about what Hansaram thinks about this deal, but I really dont think thats fair. Everybody loves a good dose of freedom.Least of all, your center of mass is entitled to it. Mine likes to wander about and take a good look around, usually scaring innocent bystanders in the process. The first sign of danger, and the poor thing runs right back into the safe confines of my belly.
Anyhow, what I did was, I took a simulated biped. Did about 9 pages of tedious calculations and tried to find how much the center of mass gallivants about while its poor body was trying to walk. Turns out it wanders out quite a bit without the hapless owner having a say on the matter. The final simulation had big errors mainly i think due to my assumptions on the inverse kinematics (thingie which works out the angles the feet and legs need to make to move about), basically my upper body toppled as i walked. Thats a bug i need to fix, but i still managed to nail the basic relationship. It was tedious but fun.
I am just back from presenting this bit to the lab, telling them that hansaram needs this thingie too. presentation started with a minor glitch with prof getting offended slightly by my hand in pocket stance but things smoothened out and managed to end with applause effectively droning out a seniors pertinent complaints that the results are meaningless, on account of programming errors. Im sure of the math though, so i guess bugs can be fixed. Professor now wants me to think about an implementation for hansaram. I want to go sleep.
If your still hanging around then i guess you must really be perseverant. In which case, I grant you a once in a lifetime opportunity to see my report and play around with my source code. My personal webpage is currently experiencing slight technical difficulties, but im fine with emailing the stuff, so just let me know, and Id be glad to help with additional info.
Tuesday, January 16, 2007
Reboot
After a long hiatus... no
Its been a while... no
Well, Im back...no
I guess by now, every possible cheesy/stylish/rhetorical/philosophical/enthusiastic/charming/triumphant i-return-to-blogging post has already been made . It shall therefore suffice on my part, to resume service with this short announcement:
For the record though , this blog shall henceforth persevere to talk about my travails and misadventures in robotics, and the world in general.
Its been a while... no
Well, Im back...no
I guess by now, every possible cheesy/stylish/rhetorical/philosophical/enthusiastic/charming/triumphant i-return-to-blogging post has already been made . It shall therefore suffice on my part, to resume service with this short announcement:
- I am alive and kicking (and occasionaly getting kicked).
- I still can type and am still faking a coherent thought process.
- I shall hence resume, this blog shall hence reboot.
For the record though , this blog shall henceforth persevere to talk about my travails and misadventures in robotics, and the world in general.
Monday, September 19, 2005
Friday, July 01, 2005
Wednesday, June 29, 2005
The Lord of the Rings : A tale of a Book-Mood
What is a Book Mood?
I’ve realized something rather recently. It’s about the Book-Moods I’ve been having. I would define a Book-Mood as the weird frame of mind you end up during/after reading a book. It’s strangely akin to sensations such as getting high or listening to death metal but not quite the same. What causes such strange phenomenon? The act of drowning into a book, swimming with the characters and being pulled down into the depths of the plot. In simpler language, its all about over-reading a book. Music has a term for such like: ear worm (a tune that doesn’t leave your mind whether you like it or not). I am sure many of you would have experienced similar sensations. I recently suffered greatly on account of a really long Recent Book-Mood I have had:
About The Lord of the Rings Book-Mood
If the reader is successful enough to not get lost among the myriad characters, then he comes to one of the toughest Book Moods in all of English literature. The reader soon begins to picture himself as Aragon/Gimli/Legolas/Frodo/Gandalf (choice depending on age, sex, height, skin colour, IQ level and sexual orientation). The world then warps itself appropriately to suit the viewpoint of the reader whatever the character he chooses. In my case, it was Aragon. Phrases such as “Tall and dark was he…stern of glance….proud and strong..” jump every now and then into the consciousness. The worst ever memory was a trip to the Central Station of Chennai to drop my uncle for his night train to Coimbatore.....
There and Back Again
The journey was to be to the Castle of the Trainwright (Chennai Central Station) whereupon, my Uncle was to pursue his destiny alone. Loremasters (My grandfather knew all train timings by heart) forecasted the correct time for departure (7:30 PM to catch the 9:00 PM train in Chennai Traffic) and I started by mounting my noble steed, proud and tireless (Suzuki Samurai TN07E2636), from the land of Rohan afar (it was a second hand buy from a showroom). The long and perilous journey was to be undertaken under the cover of the very storm of Mordor (smog of Chennai traffic). I bade my uncle to sit behind me, as my steed began with a triumphant neigh (It didn’t start to well so I have to give it a nice raise, to warm up the two-stroke engine). The journey was mostly uneventful as my noble steed galloped away heedless of the burden upon its back but it was beginning to get weary within sighting distance of the destination (Carburettor was clogging up and it literally was sputtering). But it was a noble beast nonetheless and managed to make it without a halt for refreshment (I had filled the tank only yesterday and had serviced it about a month back). A number of evil looking Lesser Men, fell and potbellied, and yet tall of stature and dressed in the peculiar clothing of their land of Traf from afar (Traffic Policemen) waylaid us every once in the while during the journey but dared not stop us as they had troubles of their own (the peak hour traffic of Chennai). We also espied a number of fair elven folk (figures/chicks/babes) near the new fortress of Spencer (I bet, you got that one) and I slowed down to watch them pass for such folk were hard to come by these days. But throughout the journey, we were aware of the shadow of Mordor that was ever upon us, as every now and then, a foul reek assailed our mouth and noses (We had to pass across Cooum, recently rated, the most polluted river in South India). Upon reaching the Castle of the Trainwright (Central Station), I was faced with a tough choice, must I risk leaving my steed unattended open its open pastures (no parking area) where it maybe waylaid by the above mentioned Lesser men, or pain in watching it stabled along with lesser beasts (Parking lot). I decided that no Lesser Man may ever lay a hand on it so suffered to lead it to the stables. The stables were crowded with a great many animals of every colour, hue, and kind. My fear proved unfounded as the Keeper of the Stables issued me the pink parchment of ownership (parking coupon) open me giving him the honest fee of 3 Gold coins (Rupees). Then I walked back to the Castle Entrance with my uncle. Tall was I and stern of glance but that did not prevent lesser folk from touching me with awe (kicking stamping, elbowing, head butting, spitting and everything short of open fighting…the crowd at Chennai Central is exceeded only by those from T.Nagar and Kothavaalchawadi). I suffered the touch as they were but lesser mortals but was I not a Tall Man from the West? The passage to the Gates of north, where lay the Great Trains, in waiting, was swarmed with a large number of races. Very often, we were bidden to give way to sturdy Dwarves in Red clothes (porter, or Coolies) singing loudly (Vazhi..Vazhi)while shifting the huge burdens, which they bore unflinchingly upon their backs. Few and far were the fair Elven folk (Babes/chicks/figures again) for they choose to board the Wings of the Windlord (The Airport) away South at the Castle of the Planewright for their long journeys. After a long walk wherein we had to watch out for mounds, pits and dung of some unknown beast (this wasn’t an Allusion, it is the typical state of the Central Station platform), we finally reached the right carriage of the Great Train bearing the White Parchment of Seating (Ticket). But we were dismayed to find a great many varieties of Lesser Men, evil looking and very nearly Orc like of having already overrun the carriage and had filled it with their foul kind (It was an unreserved compartment and we were late). The walls were filled with their filthy scrawling (typical example was: Priyaaa I Loooooooove Yooou – Vasant). But me and my uncle were veterans of many battles and a fierce Duel followed between me and their kind as I sought to reclaim the Throne (window seat was the only kind of comfort Indian Railways allowed) that was rightfully ours, even as they screamed in a nameless tongue words of abuse (W**tha, idhu unga Appa Soththa?). They foul folk were afraid of me plainly and sought a parley by offering my Uncle the rightful Seat. We accepted and I bade my uncle a good journey. I stopped only briefly to gaze at the huge Beast that was to pull the carriage train (WAP-5 Diesel Electric Locomotive from Erode) as I turned towards the long journey back home. In my haste to get back to the safe confines of my own land, I was waylaid by the Lesser men of Traf who issued forth a challenge (License Irukka?). Whereupon, I drew out the Jewel of Lisc (my drivers license), of which it was known far and wide. They trembled with fear on seeing that and hastily bade me to be on my way. Weary was I when I returned….
I’ve realized something rather recently. It’s about the Book-Moods I’ve been having. I would define a Book-Mood as the weird frame of mind you end up during/after reading a book. It’s strangely akin to sensations such as getting high or listening to death metal but not quite the same. What causes such strange phenomenon? The act of drowning into a book, swimming with the characters and being pulled down into the depths of the plot. In simpler language, its all about over-reading a book. Music has a term for such like: ear worm (a tune that doesn’t leave your mind whether you like it or not). I am sure many of you would have experienced similar sensations. I recently suffered greatly on account of a really long Recent Book-Mood I have had:
About The Lord of the Rings Book-Mood
If the reader is successful enough to not get lost among the myriad characters, then he comes to one of the toughest Book Moods in all of English literature. The reader soon begins to picture himself as Aragon/Gimli/Legolas/Frodo/Gandalf (choice depending on age, sex, height, skin colour, IQ level and sexual orientation). The world then warps itself appropriately to suit the viewpoint of the reader whatever the character he chooses. In my case, it was Aragon. Phrases such as “Tall and dark was he…stern of glance….proud and strong..” jump every now and then into the consciousness. The worst ever memory was a trip to the Central Station of Chennai to drop my uncle for his night train to Coimbatore.....
There and Back Again
The journey was to be to the Castle of the Trainwright (Chennai Central Station) whereupon, my Uncle was to pursue his destiny alone. Loremasters (My grandfather knew all train timings by heart) forecasted the correct time for departure (7:30 PM to catch the 9:00 PM train in Chennai Traffic) and I started by mounting my noble steed, proud and tireless (Suzuki Samurai TN07E2636), from the land of Rohan afar (it was a second hand buy from a showroom). The long and perilous journey was to be undertaken under the cover of the very storm of Mordor (smog of Chennai traffic). I bade my uncle to sit behind me, as my steed began with a triumphant neigh (It didn’t start to well so I have to give it a nice raise, to warm up the two-stroke engine). The journey was mostly uneventful as my noble steed galloped away heedless of the burden upon its back but it was beginning to get weary within sighting distance of the destination (Carburettor was clogging up and it literally was sputtering). But it was a noble beast nonetheless and managed to make it without a halt for refreshment (I had filled the tank only yesterday and had serviced it about a month back). A number of evil looking Lesser Men, fell and potbellied, and yet tall of stature and dressed in the peculiar clothing of their land of Traf from afar (Traffic Policemen) waylaid us every once in the while during the journey but dared not stop us as they had troubles of their own (the peak hour traffic of Chennai). We also espied a number of fair elven folk (figures/chicks/babes) near the new fortress of Spencer (I bet, you got that one) and I slowed down to watch them pass for such folk were hard to come by these days. But throughout the journey, we were aware of the shadow of Mordor that was ever upon us, as every now and then, a foul reek assailed our mouth and noses (We had to pass across Cooum, recently rated, the most polluted river in South India). Upon reaching the Castle of the Trainwright (Central Station), I was faced with a tough choice, must I risk leaving my steed unattended open its open pastures (no parking area) where it maybe waylaid by the above mentioned Lesser men, or pain in watching it stabled along with lesser beasts (Parking lot). I decided that no Lesser Man may ever lay a hand on it so suffered to lead it to the stables. The stables were crowded with a great many animals of every colour, hue, and kind. My fear proved unfounded as the Keeper of the Stables issued me the pink parchment of ownership (parking coupon) open me giving him the honest fee of 3 Gold coins (Rupees). Then I walked back to the Castle Entrance with my uncle. Tall was I and stern of glance but that did not prevent lesser folk from touching me with awe (kicking stamping, elbowing, head butting, spitting and everything short of open fighting…the crowd at Chennai Central is exceeded only by those from T.Nagar and Kothavaalchawadi). I suffered the touch as they were but lesser mortals but was I not a Tall Man from the West? The passage to the Gates of north, where lay the Great Trains, in waiting, was swarmed with a large number of races. Very often, we were bidden to give way to sturdy Dwarves in Red clothes (porter, or Coolies) singing loudly (Vazhi..Vazhi)while shifting the huge burdens, which they bore unflinchingly upon their backs. Few and far were the fair Elven folk (Babes/chicks/figures again) for they choose to board the Wings of the Windlord (The Airport) away South at the Castle of the Planewright for their long journeys. After a long walk wherein we had to watch out for mounds, pits and dung of some unknown beast (this wasn’t an Allusion, it is the typical state of the Central Station platform), we finally reached the right carriage of the Great Train bearing the White Parchment of Seating (Ticket). But we were dismayed to find a great many varieties of Lesser Men, evil looking and very nearly Orc like of having already overrun the carriage and had filled it with their foul kind (It was an unreserved compartment and we were late). The walls were filled with their filthy scrawling (typical example was: Priyaaa I Loooooooove Yooou – Vasant). But me and my uncle were veterans of many battles and a fierce Duel followed between me and their kind as I sought to reclaim the Throne (window seat was the only kind of comfort Indian Railways allowed) that was rightfully ours, even as they screamed in a nameless tongue words of abuse (W**tha, idhu unga Appa Soththa?). They foul folk were afraid of me plainly and sought a parley by offering my Uncle the rightful Seat. We accepted and I bade my uncle a good journey. I stopped only briefly to gaze at the huge Beast that was to pull the carriage train (WAP-5 Diesel Electric Locomotive from Erode) as I turned towards the long journey back home. In my haste to get back to the safe confines of my own land, I was waylaid by the Lesser men of Traf who issued forth a challenge (License Irukka?). Whereupon, I drew out the Jewel of Lisc (my drivers license), of which it was known far and wide. They trembled with fear on seeing that and hastily bade me to be on my way. Weary was I when I returned….
Monday, June 27, 2005
To Workout or not to Workout... or to over Workout
The entire period of the last month or so has been spent with a vain attempt to cut me down in size, by myself of course. Faced with a 98 kilo bulk (And a big Spare Tire around my waist) and eons of free time till august 24th when I shall make the proverbial escape.. (uttered Vivek style) to Korea, I have been given the ultimatum to lose weight by my mom. But then the Anna University Alumni Club, of which my dad was a member, happily opened up a new well equipped AC gym, and to my pleasant surprise was open for both sexes. Needless to say, I astonished my parents by signing in right away and then on 'gymmed' hard. The place was for the most part was and is occupied by fifty plus retirees who are in a desperate fight against an aging heart/blood sugar/bulk etc. The flip (and the bright) side to this is that some of them bring their daughters/grand daughters along (and I am the only eligible bachelor around not counting the former Mr.Chennai body builder that is the Gym instructor). Well then, the story now moves on predictable lines as I took to heavy 'bicepping'. The place was surrounded by mirrors and I liberally helped myself to a vareity of weights, dumbells etc. and my instructor was none too pleased to help me on. The very same day, I felt my biceps to be stiffer and I felt proud. The stiffness turned to a mild pain the next day. The instructor bushed it of by saying it was normal and uttered the age old adage "No Pain, no Gain". Well I must have gained a lot apparently for the day after that, I found to my horror that I couldnt straighten my arms for more then 100 odd degree without uttering a wraithlike shreik. Imagine how ridiculous this looks for a mommnet. I spent the next 2 days, walking around like a forlorn velociraptor, hands held in front at a 90 degree angle. Worse was to follow, the calls of nature severly compounded the matter. Thankfully my dear mom then undertook to tie hot water bandages on my arm and now the pain seems to be subsiding. Its been a week since this episode and my arm (especilly the left one) is still refusing to fully straighten. The instructor promised to attack my thighs and abdomen next. Needless to say, I havent been to gym again since.
Subscribe to:
Comments (Atom)
