Wednesday, December 30, 2015

CADS

When you are starting up a FIRST robotics team it is fair to say that you are making things up as you go.  Sure, you can read how others have done it, but everyone has different circumstances.  You have to go with your strengths.

Our fledgling team has several, including a really great work space.  One of our sponsors is a place called Machine Tool Camp.*  They refurbish huge, complicated CNC** machines.  But as a...well a hobby I suppose, they have created a Maker's Space.

Our robotics team will be the first real users of the work space as it by happy coincidence is being finished off just in time for us.

It is what I call Robot Building Disney Land.  In addition to the necessary creature comforts (bathroom, coffee machine, kitchen) it has computer work stations and most importantly for our purposes a serious metal fab shop.

Rookie FIRST teams do not, as a rule, finish high in the standings.  So our goal will be to exceed the low expectations of first timers and to look darned good in the process.

So, if you have access to software and computerized milling equipment that will allow you to do fancy, complex and artistic metal fabrication, what do you do?


You start a pre-build season series of classes for students and coaches.  Lets make fancy stuff out of hunks of metal!

And I have to say, some of these kids are Scary Smart.
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* Of necessity my blogging on FIRST robotics will have a bit less anonymity than my usual bill of fare. Being as I am semi retired I guess that is OK.

** For the uninitiated CAD is Computer Assisted Design.  CNC is Computer Numerical Control. The first term is essentially designing things on computer.  The second refers to feeding the design parameters into a computer that can control metal fabrication machines and build the part for you.

Monday, December 28, 2015

Christmas 2015

"I wonder what normal families do for Christmas?"

I asked that on Christmas Day.  I'm guessing for instance that our ongoing tradition of setting up a Christmas tableau on the neighbor's lawn under cover of darkness is a bit atypical.  This year we had a jousting theme with one participant being Santa Claus riding a snow blower and wearing a Jason mask...


I like the old Pontiac hubcap used as a shield.  Oh, also note the poor gnome stuck in the intake...


Of course we do give presents.  I found some really swell Amish themed pint glasses at the surplus store.


But I was out done by one of our lads who fancies himself a writer.  He came up with a five page manifesto feverishly hammered out on a manual type writer.  Chock full of cryptic allusions to plots and conspiracies of course...


As to presents for me, I did pretty well considering my Naughty score for the past year.  I got a couple of swell outfits for Bill the Squirrel and some sausage guaranteed to be made from genuine feral pigs.

Ah, but these are trifles.  The biggest gift was the presence of the younger generation(s).  All are doing fine.  And with a new baby in the house for the first time in 22 years the mood is definitely changed.  Rocking, bouncing, mugging to try to induce precious smiles.  Old songs that have lain dormant for a quarter century are haltingly recalled, then after a rusty line or two come back in perfect execution.

I hope you all got some good swag from the big  guy in red wearing the hockey mask.  I treasure all my presents including a shoulder full of warm spit up.

Wednesday, December 23, 2015

Christmas Shopping?

Hey, I'm not very good at shopping.  I can only stand doing it for short periods of time and at stores where I can find interesting things to look at.  Not buy usually, but look at.

The local Guy Stuff Store is usually fun.


I am not sure how this works.  Does it give Fido a squeeze or an electric shock if he barks? Seems to me that would actually increase Dog Anxiety.  I also wonder if there is a human version.


Mealworm Frenzy. Kind of says it all.


I am puzzled by this one.  Tarsal is a medical term that refers to the ankle.  So basically this stuff is called "Big Foot".  I don't want Big Foot to feel I am intruding on his territory.


This at least might have some practical application.

Monday, December 21, 2015

Ten Cents worth of History

It didn't belong there.

I was at a college surplus sale.  You go there to pick up slightly out of date computer equipment and sturdy yet clunky storage shelves that you usually regret buying.  I got a few things; a coffee maker for a buck, a phone for the cabin, nothing great.

So why was there a box of bowling trophies?  I already have too much kitschy stuff laying around but trophies sometimes get re-purposed as awards for my robotics competitions.  So I grabbed the best one.  Heck, it was only ten cents and I think you will agree, its a beauty.



Traditionally it is baseball that is considered to be the sport that defines the character of America.  I won't argue the point here.  But if you specifically wanted to understand Middle America, that chilly flyover land seldom seen on the news, I think bowling could stake a rival claim.

People bowl on teams.  They wear slightly silly uniforms.  Unlike baseball you can eat a cheeseburger and fries while participating.  Until recently you could smoke.  Bowling is a game that is rooted in small town tradition but present in larger places.   It tends to be an older person's game but kids do it also.  For years it was one of our Christmas family traditions.

There is an entire set of non visual features of bowling that are every bit as distinctive as baseball. The rumbling progress of the ball with the sudden crash of impact on the pins.  The tactile rush of air from the little hand dryer built into the ball return.  The faint smell of cigarettes that while ever diminishing will probably never vanish entirely.

So, my dime's worth of American history?


Feit's Lanes was a classic small town bowling alley/bar in Park Falls Wisconsin.  I found a couple of images of it.  Here it was in its heyday:


It is actually for sale now.  Looking over the prospectus I had a hard time reconciling the pictures. But with the old facade apparently sheared off and replaced with something unfortunate, this is Feit's today:

The information that accompanies this says that the bowling alleys were torn out years ago making a larger space for bands, gatherings and so forth.  I saw this photo and just got sad.


For over sixty years Feit's Bowling alley and bar was run by a Robert A. Feit.  You can probably imagine him in your mind.  Tubby guy with a crew cut.  Always talking. He likely had a million stories, none of them true.

But you would be wrong.  Very wrong indeed.

Robert Feit was born and raised in Park Falls.  In 1946 he came back to marry his sweet heart and settle down.  But for a few years he was a member of the United States Marine Corps First Raider Battalion, also known as Edson's Raiders.  Wounded, many times decorated, he saw some of the most ferocious fighting of the Pacific War, as a member of a truly elite military formation.

I bet he kept the crew cut.  The years do tend to leave their mark on our once trim waists.  But the stories... I bet most of the ones we would actually tell you were true.  But he didn't talk that much and the stories he wouldn't tell you were the truest ones.

Robert Feit 1926 to 2007.  Semper Fi.




Friday, December 18, 2015

One Pound Prototype Robot

When I first started doing the middle school combat robotics course we had one and three pound weight categories.  This paralled the categories used in "official" competitions.  But the one pounders, known as ant weights, were never very exciting.  With that small a weight allowance you just could not build much beyond a simple pusher.  Or at least you had a very difficult time doing anything fancier such as adding a powered weapon.  So we have been all three pounders for several years now.

But things are changing.  As I started looking around at ways to move beyond simple hacked servos for robot drive I came across these:

Ebay has a ton of them for sale, with prices in the four or five dollar range once you factor in postage. So cheaper than a servo, but they still need something to control them.  A solution suggested itself...

Here is your basic - roughly one pound - robot.  Nothing more than a couple of  hacked servos, a battery and a radio receiver.  Not particularly zippy, but to be fair it seemed to have an excess of duct tape on one wheel that was catching...
video

I think we can do a little better than that.

Below are a pair of the bright yellow gearmotor/wheel combinations from China via the miracle of ebay.  The fact that they come with perfectly fitting wheels is a big help, fashioning sturdy, reliable hubs can be pesky and time consuming.



The little green circuit boards soldered on to the motors are my solution to the issue of control.  They are just the electronics pulled from servos.  Sure, why not?  I have a big box of them that have come to grief over the years of doing the event and they appear to have plenty of extra capacity.  So long as you run them at 6 volts they are unlikely to go up in smoke.  The slender wires act as sufficient resistance that I don't see any way to "over amp" them even if you did try to push an immobile object with them.

Here is the above platform with the servos swapped out for China Gear Motors.
video
Way faster.

As with my Proto3 robot a few thoughts on practicality.

Weight: above was, with battery, about one ounce under a pound.  There is room for improvement of course, the frame I borrowed had been heavily baptized with glue, and was larger than needed anyway.

Adaptability: OK.  I think enough weight could be spared to allow for either a four wheel version or a simple weapon running off the 6 volt drive battery.

Effectiveness:  It was not as effective a pusher as I would like, probably the gearing is set for speed over torque.  Four wheel drive would help a lot, and also make it easier to handle.

Challenge to Learning ratio: again I have to worry about making this too easy.  It was not at all difficult to toss this together in a few minutes.  Other than pulling the servo guts out and doing a little nimble soldering work, I don't see how the urchins would be kept occupied for very long.

Cost: feasible.

I am looking at several other options as well.  Some time into next year I may have to revisit this.


Wednesday, December 16, 2015

Three Pound Prototype Robot

Although my middle school combat robotics class has been both successful and fun for many years now I have been tinkering with the idea of a technology upgrade.  In part to keep it more interesting. And in part because we can.  Electronics in particular have gotten so much more affordable recently.

But anything I would do would have to fit the spirit of the class, which is cheap and fun.  It would also have to be within the dubious skill set of middle school students.  And would have to be feasible within the somewhat cramped confines of our Machines Behaving Badly combat arena.

So eliminating any elements that would be too complex, too expensive or perhaps too speedy for a confined space, what's left?

Some of the Minions who come over to help with the event suggested this motor, widely available on ebay.

They claim to put out 1000 rpm at 12 volts and come well recommended for durability.  But still, at about ten bucks including shipping, they are not quite the bargain of our hacked servo drive systems. Or at least they did not look to be, then I found a bag of 18 similar motors that I ordered years ago and never got around to using.  I should clean the workshop more often.



428 rpm at 9 volts sounds good, we will actually be running at 9.6. Assuming two per robot, if I toss in the ones I already have we are down to an affordable price per machine.

I made some hubs out of plastic squares from the surplus store.  Just tighten that little set screw...


Motors with attached hubs/styrofoam wheels going on.  I am using cheap and easy cable ties and hot glue here, but there are nice mounting screws on the front of the motors.


And...the finished product.


If you are keeping track of such matters, that is a standard 9.6 volt RC car battery.  I don't doubt that the system could handle more voltage but these are cheap and sufficient.  That is a standard Futaba FM 75mhz receiver, it runs with the free Vex transmitters I have been using.  The green board is an older model Scorpion speed controller.  This could be the rate limiting problem for us.  I have to do some ebay prowling and tinkering, but most of the ultra cheap speed controllers have suspect reliability.  And even the cheapest equivalents to the above unit are around 35 bucks.  Of course it is quite possible to swap speed controllers from one machine to another for a season or two as we build up stock.

On to the testing.

Speedy enough?
video
Yep.  The controls are a bit glitchy due to a conflict between the on board mixer of the transmitter arguing with that of the speed controller, but that is fixable.

How about pushing power?
video
If you can push a tool box around you can push another three pound robot.  Keep in mind that the box has a lot of friction from its surface area and that my tossed together robot does not have anything on the wheels to enhance traction.

So, lets pass judgment on the prototype.  We need to make it fit the budget which at present is about 20 dollars a machine.  If I scale the class size back from 24 to 20, and toss in the 9 robots worth of motors I already have, then assume I can get some kind of bulk deal somewhere, I figure motors will be around 200 dollars.  The cheapest speed controllers that look up to the job are about 35 each.  If we swap from one machine to the next, lets say we need six.  I might be able to shave a bit off the cost there as I plan to shop a few of the cheaper "mystery electronics" controllers from ebay.

Other costs should be fairly minor.  We will need more 9.6 volt batteries but our stock is good there as is our "in event" charging capacity.  Wheels, hubs, electrical connectors all are minor issues.

The prototype as shown above is only 1 pound 9 ounces so there is room for armor, weaponry, decor, etc.

One problem I note is that this is a little too easy.  Tossing together Proto3 took an hour or so of tinkering.  My charge is to keep the kids engaged for six or seven sessions of two hours each.

Another option I have considered is reviving the earlier dual path event, having one and three pound machines in their own brackets of course.  To that end I also tinkered with a Proto1 robot.......


Monday, December 14, 2015

CCC Camp Delta

Civilian Conservation Corps camps are fairly numerous in northern Wisconsin.  Camp Delta is one that we had driven by often on our way to the Delta Diner, which is the only - but most excellent - reason to visit the tiny hamlet of Delta.

Some CCC camps lead you on a merry chase, but this one is easy.  It is right on CCC road.  And the original stone and concrete entry pillars still stand.


I am very curious as to what was mounted on the pillars, note the square slots near the top.

Camp Delta existed from 1934 to 1942.  It lasted longer than most CCC establishments, perhaps this accounts for the abundance of remains.  Early and transient camps were improvised out of wood and local stone.  When a place was around for a while more permanent concrete buildings were erected.

This is public land so a walk around on a brisk November morning is no problem.  If you go, as I did, on opening day of deer hunting I suggest wearing red or orange.  That fuzzy brown jacket....not a good plan.


From a post card I have seen I suspect this large and well preserved foundation is from a combined garage and warehouse.


No idea really.  

More of the classic CCC big squares of cement.  In this case adjacent to a depression from a basement.  Perhaps over engineered front step for a barracks?


The bottle is newer than the CCC era.  The fire brick is about right.

Saturday, December 12, 2015

A Peace Offering to my Vegetarian Friends

Sorry about the themes this week. Really.  I don't know what got into me.  Instead of happy holiday posts you got stuff about rendering carcasses, using beetles to clean skeletons, and the sad demise of faithful pets.

If folks generally, and my meat averse friends specifically, want to pummel me with over ripe produce, well I found just the thing down at the local market:


I have tried your patience enough this week so I won't go into the etymology of this name, it is at best obscure.  And if you were feeling a bit Latin as you hefted one of these to chuck in my general direction you might be pleased to know that the scientific name for them is Citrus Maxima.


Friday, December 11, 2015

Doggoned Odd

Small American towns like to have parades.  Fourth of July, local festivals, really any excuse will do. At such events you get a broad spectrum of participation.  The school marching band. Beauty queens smiling and waving.  Politicians doing the same thing.  Sports teams, church youth groups, etc.

Often they hand out or toss out items of trivial value for the spectators.  Candy, of course well wrapped, is the usual.

I was out of town but last week my Better Half attended our town's annual holiday parade.  Balmy weather ensured a record turn out.

One of the give away items tossed into the crowd was this:


I suppose it is fairly apparent that this organization is providing hospice, euthanasia and cremation for your pets and not for you.  But they don't exactly spell it out as clearly as they maybe should.

And I thought including the biscuit was a bad idea.  How in fact do we know it is not one of their special "euthanasia biscuits*"?  It's not as if dogs usually cast a quizzical eye at food items, sniff them carefully and then take a sample nibble before deciding if it is actually safe to eat.

I don't mean to make fun of the people running the business.  They provide an important service and would simply have to be the sort of folks who left a client's house with a tear in their eye.  Dogs give us so much.  They provide the entire circle of birth, joy of childhood, responsible adult life then decline and departure.  All compressed into a much shorter than human span and so all the more precious for each moment.

It made me think of the one bit of literature that makes me cry each and every darned time I read it:



It also makes me want a dog.
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*Pretty sure that Euthanasia Biscuits is another of those bands that my pal Sunny goes to see...

Wednesday, December 9, 2015

Picked Clean

Sometimes I am driving along, places to get to and things on my mind, when I just have to stop the car and grab the camera.  This for instance, was not something I was expecting to encounter:


So very many questions.  I don't know where to start.

The crudely lettered sign encouraging you to drive up into the hills for instance.

But what the heck are Beetle Cleaned Skulls? Other than I presume. another of those horrid bands much beloved by one of my London pals who is quite into the club scene....

Actually there is a lot of info on this matter, very little of it dealing with missing person reports.

As it happens there are specialized beetles called Dermestidae that are much prized by taxidermists and natural history museums for their amazing ability to clean up skeletons.  They quite literally pick the bones clean and I have to assume that little Dermastidae larvae never have to listen to lectures on finishing everything on their plate because some hypothetical larvae in Africa would for sure like to eat that last bit.

You could - if perhaps you are not already on enough government watch lists - purchase your own little colony of skeleton cleaning Dermestidae on ebay.  Some of the various and frankly fascinating taxidermy sites I visited advise caution, intimating that these low grade beetles are often infested with mites and that you are not likely to get too many hard working generations from the run of the mill beetle vendor.

One link I encountered was for lack of a better word, magnificent.  The University of Michigan Museum of Zoology has a long treatise on the use of Dermestidae.  It is informative, well written, and I think even contains a few elements of subtle humor.  I always say it isn't a good day unless you learn something new.  HERE, this will take care of a couple of weeks worth of new information....

Now some of my gentle readers might be a bit squeamish for this sort of thing.  I totally understand. So for brevity I will just pass along a few high lights.

The container in which skeletons are cleaned is a Dermestarium.

The best food to get a colony up and running is pellets of Purina Trout Chow, although various dog and puppy chow options would probably be fine and easier to get hold of.  You need to keep the chow nice and dry so as to reduce the occurrence of "Museum Mites" which I now know are the bane of all natural history museum curators.  I take comfort in times of crisis that there are a few disasters that I will never have to deal with....

Dermestids hate mummies.  All that movie stuff about beetles pouring out of dried up Egyptian dudes turns out to be a bunch of Hollywood nonsense.

And I did like the discussion of alternate methods of bone cleaning.  "Enzyme Detergent Soup" seems like something that you would have to stock very carefully and nowhere near the museum's staff break room.  And as to "Manure Pile Maceration", I can tell you that really works.  Here is a skull that came up at our dig in Vindolanda.  It is amazing how clean bones look after 1800 years in anaerobic layers of horse manure.

The world of the ancient Romans seems far away in time but familiar in other ways.  The world of museum curators actually seems more alien to me.  I will close with an enigmatic quote from the University of Michigan site:

"There is a wide variety of opinion on degreasing specimens. In the UMMZ, for example, the fish people don’t care to have their specimens degreased. They say that is part of the fishy ambiance that they like in their work. On the other hand the bird division has an almost fetish desire to degrease their specimens."


Monday, December 7, 2015

Promptly and with the Hides On

There can't be too many things more difficult to photograph than an entire yard stick.

Too bad, some of them have fascinating advertising on them.  One of my favorites is featured today but I had to take the pictures in overlapping segments.


I consider this a highly effective ad.  I mean, if there is one thing you are looking for in the matter of dead animal removal, promptness would be it.  Not having to skin the defunct critter prior to said removal, well, better still.


Wait.....you're going to pay ME to take away the dead animal?  It can't get much better than that!  I tried to do a bit of internet sleuthing on the phrase "Sanitary Green Truck".  It seems to  have been widely understood back in the 1930s or 40s to which this artifact dates.  But I drew a blank.  Oh, I am sure there is some reference somewhere but those search terms hide it under myriad references to "Green" recycling services.


Obviously dead animals had some monetary value to the Chippewa Falls Rendering Company. Rendering is one of those lines of business that pretty much everybody would prefer not to think about too much.  There are no doubt big vats.  And if you worked there you would come home at the end of the day with smells on you that showering would not touch.  You may not have had many friends, other than the guys at work of course.

Rendering is an interesting word.  You can chase it all the way back to Latin where reddere meant "to give back, restore or return".  In that sense rendering unto Caesar meant giving him his denaris back. In the Middle Ages it meandered through French and picked up related definitions.  When a jury comes back with a decision it "renders" it.  The sense in which render is used above is that of extracting fat and does not turn up until 1792.  The related term rendition as it applies to performances of plays and songs is later still, from the 1860s.  One wonders if drama critics had the foul stench of a local factory in mind when they started using it in this fashion.

Rend, by the way, in the sense of tearing has nothing to do with rendering.  That comes from  rende, a Germanic source word that also gives us rind and rent.
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Be forewarned, it is going to be a week of slightly odd stuff.......

Friday, December 4, 2015

Still Standing Watch

On a commanding hill top the ancient stone circle still stands defiant, as if daring a long vanished enemy to attempt one last assault upon its yet redoubtable walls.


But that can't be right.  This peculiar structure is in northern Wisconsin.  We don't have castles here. And what passes for an enemy is the rivalry between the Green Bay Packers and the Minnesota Vikings.  A descent to medieval warfare between them can't be ruled out entirely, but hardly explains this substantial structure a mile or so north of Drummond, Wisconsin.  A few more pictures to give you some clues.  I actually did figure this out, and was surprised.


Thick walls, stone and cement.  They still stand about 10 feet tall on the outside and 20 on the inner aspect.


I have seen smaller castles than this.  It has been abandoned long enough for a birch forest to grow inside, and for some of the upper bits of stone work to fall away.  No doors, no windows.


We sit high up on a hill.  The anomalous looking park bench affords a good view of a lake down below.


There seems to have been considerable effort to apply a smooth coat of mortar to inner and outer surfaces.

This last of course was the big clue.

In the 19th century northern Wisconsin was really only good for one thing.  Lumber.  In the early 1880s the Rust Owen Lumber company built a huge mill and set up Drummond as a company town. Because fire was a huge consideration the company built this reservoir, basically an emergency water supply for fire fighting, on the tallest nearby hill.  Pumps would fill it from the lake down below.

I was puzzled by a couple of things.  The distance from town seemed wrong.  But the lumber mill was closer and I assume the Company cared more about saving it in the event of conflagration.

Also, where are the pipes?  I found a source that describes water being pumped up the hill from the lake to fill the reservoir.  But for fire fighting purposes they had hydrants set up in the lumber yard. The plumbing from the reservoir to the hydrants was made of what they had plenty of....wood. Cedar strips were coated with creosote and bent together into water conduits.  These of course are long, long gone now.

I liked this last detail.  It is pretty much how the Romans did things back in the day.  And I understand that under New York City you might still find a few ancient water pipes made of snugged together and hollowed out logs.
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There is something Tolkienesque about this lonely ruin.  The Professor's works of course contain a suitable quote:

"But long before, in the first days of the North Kingdom, they built a great watch-tower on Weathertop.  Amon Sul they called it.  It was burned and broken, and nothing remains of it now but a tumbled ring, like a rough crown on the old hill's head."

Wednesday, December 2, 2015

No thanks, King Neptune

Although I am a fan of most nautical traditions I have to admit that some of them were rather unpleasant and atavistic.  With a nod - or better still a tug of the forelock - to tradition, some should now fade into history.

For instance, the long standing tradition of ceremonies when a ship crosses the equator.  You can read up on it if you are interested but it was essentially an elaborate and often unpleasant hazing where veteran sailors got to pick on those newer swabs who were crossing this arbitrary line for the first time. People dressing up in drag, a kangaroo court presided over by King Neptune, you get the general drift of it.

It is hard to see much benefit in it other than relieving ship board tedium.  The "polliwogs", as they called the newbies, were really no different from the day before they crossed into the other hemisphere. Nor was the ship really.  There were still decks to swab, watches to be stood, weevily biscuits to be eaten.

I doubt these little pageants provided anything more than a brief boost in morale.

We still do this sort of thing.  Oh, not the equator crossing stuff, that has been phased out of pretty much all the navies on earth.  Cruise lines still do a very watered down, sanitized version.

But there are other arbitrary lines to be crossed.  When people turn 50, or 60.  Or get married.  Or most emphatically, when they retire, there are odd rituals that seem to be expected.

At least the bachelor/hen parties have a bit of fun to them.  Rather like a last burst of unfettered exuberance before the presumptive long slog of married life.

But high denomination birthdays?  Unwanted gifts of black balloons, dead flowers and worse. Bad taste generally in my opinion, and working in a field where I often have to deal with the reality of disability, decline and demise.....suffice it to say I find this kind of humor to be very thin gruel.

And even odder is the response to retirements.

In the modern economy very few people work their entire career in one place.  New hires arrive, stay a while and move on.  In larger organizations they are simply people with ID badges you pass in the hallway.  And even in a smaller, more personal setting...the feelings about someone leaving can be complex.

Some will be genuinely sad to see you go.  Others might be happy, either for you or that they will be rid of you.  Some will look longingly at your escaping the confines of the daily grind while others, perhaps closer to retirement themselves, get the unsettling sense of themselves approaching an unknown abyss.

And of course "retirement" is a vague concept.  No gold watch and pension these days.  Most people who are standing down in the neighborhood of 60 are not doing so to go play golf, or wind surf,  or to do the other silly things you see in happy commercials from investment companies.  We don't step down so much as step sideways.  A different employer, a different schedule, a different locale.

So.  No cake, no candles, no balloons.  The ER has been a great gig, one that I consider the most fun phase of my career to date.  But the ship sails on with a different crew.  The decks will still be scrubbed, watches (not the gold kind) stood, biscuits and weevils eaten by someone else.

The business of making a big deal out of crossing arbitrary lines is nonsense.  You feel the same a few miles north or south of the equator and if the navigator had not pointed it out you would never have noted the transition.