#epitrochoid

[tuxpaint]

A heaping helping of examples of the Epitrochoid and Hypotrochoid tools coming in Tux Paint 0.9.32. These are the kinds of curves you get when you draw with a device like a "Spirograph" or "Wondergraph". (Roulette curves; specifically, centered trochoids.)

#epitrochoid #hypotrochoid #centered trochoids #math #mathematics #maths #open source #edtech #softwaredevelopment #digital art #tuxpaint #tux paint

[omochajournal]

すぴろぐらふで外トロコイド

#spirograph #スピログラフ #epitrochoid #外トロコイド

[nicksayers]

Two of my tabletop Bicycle Spirograph drawing machines at National Festival of Making this weekend in Blackburn. Their first proper outing since before the pandemic! They were a little rusty but still worked fine. Many colourful geometric flower patterns were drawn. It was nice to show these older pieces alongside my new record player phenakistoscope animation workshop. Both explore rotational phase patterns and hypnotic art in different ways. More soon… @thefestivalofmaking #GiantDrawingMachines #drawing #drawingmachine #spirograph #hypotrochoid #epitrochoid #artfestival #craft #stem #steam #artscience #sciart #scienceart #geometry (at Blackburn) https://www.instagram.com/p/CevLLA7opgg/?igshid=NGJjMDIxMWI=

#giantdrawingmachines #drawing #drawingmachine #spirograph #hypotrochoid #epitrochoid #artfestival #craft #stem #steam #artscience #sciart #scienceart #geometry

[da-riya]

Tried to be sneaky and just translate and copy the English wikipedia page but I feel this sloppy work would be found out

#maybe not I'm already very English poisoned #The Wankel engine has a spinning eccentric power take-off shaft #with a rotary piston riding on eccentrics on the shaft in a hula-hoop fashion. The Wankel is a 2:3 type of rotary engine #i.e. #two-thirds of its ideal total geometrical volume can be attributed to displacement. Thus #its housing's inner side resembles an oval-like epitrochoid #whereas its rotary piston has a trochoid (triangular) shape (similar to a Reuleaux triangle) #and the Wankel engine's rotor always forms three moving working chambers.[22] The Wankel engine's basic geometry is depicted in figure 7. S #not being guided by the external chamber. The rotor does not make contact with the external engine housing. The force of expanded gas press #All practical Wankel engines are four-cycle (i.e. #four-stroke) engines. In theory #two-cycle engines are possible #but they are impractical because the intake gas and the exhaust gas cannot be properly separated.[15] The operating principle is similar to #Wankel engines typically have a high-voltage spark ignition system.[25] #In a Wankel engine #one side of the triangular rotor completes the four-stage Otto cycle of intake #compression #ignition #and exhaust each revolution of the rotor (see figure 8.).[26] The shape of the rotor between the fixed apexes is to minimize the volume of #respectively.[23][27] As the rotor has three sides #this gives three power pulses per revolution of the rotor. All three faces of the Wankel's rotor operate simultaneously in one revolution. #one power pulse is produced at each revolution of the shaft. For comparison #the four-stroke piston engine completes the Otto cycle in two revolutions of its output shaft (crankshaft). The Wankel thus produces twice #Wankel engines have a much lower degree of irregularity when compared to a reciprocating piston engine #making the Wankel engine run much smoother. This is because the Wankel engine has a lower moment of inertia and less excess torque area due #a two-rotor Wankel engine runs more than twice as smoothly as a four-cylinder piston engine.[29] The eccentric output shaft of a Wankel eng #000 or 8 #000 rpm. In practice #automotive Wankel engines are not operated at much higher output shaft speeds than reciprocating piston engines of similar output power. Wa #I... Forgot I had the whole page on Wankel engines on my clipboard so I accidently pasted it

[thedailymobile]

“Will the Circle Be Unbroken: Do You Remember the Spirograph?”

“Will the Circle Be Unbroken: Do You Remember the Spirograph?”

In case you don’t remember: https://youtu.be/fOZkgejZ-U8

View On WordPress

#burgundy #carpet #circles #epitrochoids #hypotrochoids #look down #purple #roulette curves #round #Spirograph

[sspacegodd]

One of the coolest things during biblical times was Spirograph, a protractor on steroids you used to draw geometric mathematical curves called hypotrochoids and epitrochoids.

I remember a hot pink pen that leaked all over my good pants and my mom spanking me with a Hot Wheels track.

#spirograph #biblical times #hot wheels #geometry

[locrianking]

kill yourself Zionist and stay the fuck off my blog.

i’m gonna assume you already know the basic principles of combustion engines: intake, compression, combustion, and exhaust. in standard piston engines, all of the space in the cylinder handles all of those jobs. rotary engines are similar, but each of those jobs occur in different parts of the housing.

the most important parts to know are the rotor, which is the triangle part everyone jokes about, which has three, convex faces, the housing, which is a weird oval shape (also called a epitrochoid!) and is specifically designed so that the three tips of the rotor will always be in contact with it, and the output shaft, which has these lobes on it which the rotor is mounted onto. the housing also contains the exhaust port, and the center piece of the housing contains the intake port.

so, rotary engines use the same four-stroke cycle that piston engines use, they just go about it in a really funny way! as the rotor rotates throughout the housing, it creates three chambers that change size throughout the revolutions, not unlike how the up-down motions of pistons change the size of their chambers as they move.

air/fuel enters the engine through the intake port when the rotor passes by it, and that chamber gets progressively bigger until the peak of the rotor passes, at which point it is sealed off. after that, the volume/chamber begins to shrink and the air/fuel mixture gets compressed as the face of the rotor gets closer to the spark plugs. yes, plural! rotary engines have 2 spark plugs instead of 1! the rotor’s face reaches the spark plugs and then we have combustion! combustion creates gases that need to expand, and the chamber for that grows as the rotor continues along its way. this is where power is created btw! eventually the rotor passes by the exhaust port, all of those gases leave the chamber as exhaust.

here’s a gif from wikipedia if you’re a visual learner:

rotary engines are super neat! their most well-known usage has been in mazda sports cars, mainly the rx-7 and rx-8 (fun fact: the rx stands for “rotary experiment”!) but also from the legendary mazda 787b herself. they’re not the most efficient or reliable engines, but they’re beautiful in and of themselves and i’m so excited that mazda has continued to carry on the legacy of the rotary. i can’t wait to see what we do with this technology in the future :DD

#rosie speaks #tag: automotive enthusiasm #suicide #suibait #i/p conflict #the most absurd part is that they said to stay off their blog but theyre on fuckin anon lol idk who you are #anyways just so we’re clear: i support and believe in a free palestine and i also believe in the jewish right to their indigenous homeland #i do not support the israeli government and i do not support hamas #i also have been regularly donating to help palestinian civillians gain access to esims as well as menstrual products #i’ve been on this site for almost 10 fuckin years lol (since i was 10/11ish) #do you really think telling me to kms means anything? lmao cope harder #i know what i believe in and telling me to kms doesn’t mean shit.

[writer59january13]

The daily star Tuesday issue... announces Summer Solstice 2023

regarding ray zing planetary earthlings

Wednesday, June twenty first at 10:57 Ante Meridian

Eastern standard time

will find Earth's North Pole tilted closest toward sun. This demarcates most daylight hours of the year for people living in the northern hemisphere. Just shy of high noon sun (lil more than twelve hours from drafting these lines) nearest star in solar system reaches highest point in the sky.

Hence hasty intent to beat buzzer sound dashing off riding figurative one seahorse open sleigh madly awk cross cyber sea, aye rudder sally forth (slogging thru virtual flotsam and jetsam) with poetic obeisance paid to average size ball of Earth, wind and fire, my out of this world quasi stellar benediction, since Earthlings traveled thru space/time continuum circa complimenting

summer solstice at Stonehenge

when the sky clear, the sun rises

behind the Heel stone, the ancient entrance

to the circle, and rays of sunlight channelled

into the centre of the monument.

Perchance bajillion years ago, when predecessors of present day primates (coon sitter terribly less a bomb bin hubble), versus twenty first century Homo sapiens predilection for total mortal kombat graphically spiraling downward zeroing (kamikaze like), analogy drawn, viz subjective mathematical roulette curves, albeit hypotrochoids and epitrochoids staining countless grains of sand, count them yourself, yielding result (somewhere very loosely approximating 7.5 x 1018, or seven quintillion, five hundred quadrillion grains.

Such minutiae less significant within the realm of present day Homo sapiens, whose lives less linkedin with phenomena affecting life on this oblate spheroid, (which could come to a crashing halt predicated on burgeoning human population

jeopardizing sustainable planet presuming industrial paradigm prevails, thence man/ woman kind will unwittingly trumpet, and

or sound claxon (ex post facto), while warming temperatures melt glaciers, asper huge popsicles drowning multitudinous habitats courtesy of

violent meteorologic cataclysms, where Noah's ark will be big enough to save majority of creatures, and (wherein no art of the deal) savvy enough to wall off sky high tidal Katrina and the waves, then nature will (make a killing) relishing tidying Atlas sized tureen if necessary applying pledged finishing touches repurposing third rock for another species slated to inherit pseudo tabula rasa after Campbells, and broth hers detox polluted primordial soup i.e. once cleansed of poisons, thus...I condense my Green New Deal spiel!

Midwinter night dream filled

with balm of June solstice rays

lackadaisical and carefree months ideal time

to while away pronounced illuminated days

outdoor sports a favorite choice

occupies athletic population,

which venues witness frequent surge

and spill of overtime plays

another popular milieu

favorable climate awakens

constitutes habitués vacationers visit

ashore popular waterways

beachfront shoreline inundated

by mass exodus of sun worshippers

tidal seaboard awash

along every square inch

human species splashes to keep cool

within ocean and bays.

Six months ago bitter cold

and dark snow filled skies

wrought undeserved vengeance

viewed from these eyes,

who after each and

every major winter storm

donned proper attire

to stay warm outside

while clearing walkway

with shovel in hand

executed repetitive motion

akin to how boater plies

similar (yet reversed)

bodily swing of arms

now readily prepares for execution

of most difficult seasonal task

requires usage of most complex muscle

the source of poetry witty and wise.

Awake to the solar celestial sea chant

mourning regarding species no longer extant thus upon figurative shoulders of youth

tasked with survival of humanity

a behemoth nearly impossible mission

younger generations unfairly saddled

with obligatory filched grant courtesy when fossil fuels

broadcast onset of

fourth Industrial Revolutions

spewing paradigm viz

free market capitalist kant now quashing, thrashing,

wrestling against rant

long fostering Homo sapiens dominance.

Starry-eyed dark matter

of infinite space

espied by countless eons

since original human race

became cognizant of her/

his terrestrial place

gilding the heavens with strings

of pearly hued lace

closer to earth charting

early skywatchers to notice moon face

held captive via gravitational brace

while zodiac archer aims

cocked bow, where knocked feathers sans arrow complete an awesome

fantastic bullseye ace.

Mother nature’s ornery

primates supreme display said massive breastworks broadcast inlay feat of awesome accomplishment

finds yours truly humbled okay

with his feeble limitations

engendering ample rocky tsuris oy vey.

Today June 20th, 2023

after a light rain, of morning mountain dew

a strand of pearls clung

to slender tree limbs

bejeweled woody flora prismatic orbs

tell tale sign recent cloudburst

cleft darkened heavens

rained watery life source liquid

downpour laced branched canopy

awash with molecular droplets

requisite to buzzfeed

burlesque Vaudeville bluster

exquisite gala performance unrehearsed

unscripted ubiquitous theatrical performance

received limitless encores

toward Gaia screenwriter

whose infinite scope

(wrought upon natural landscape palette)

exceeds the finite abilities

of those bipedal dominatrix

human organisms imbued

whose dilettante debut

(dawned these last seconds

on the clock face of geologic history)

might witness curtain call

on their final act.

#stonehenge #summer solstice

[sergidelgado]

Rosa 🌹🐲📚🌀 #feliçsantjordi #santjordi #epitrochoid #17 #opart #opticalart #espirografo #spirograph (en Antiga Fabrica Estrella Damm)

#17 #epitrochoid #feliçsantjordi #opticalart #spirograph #opart #espirografo #santjordi

[tuxpaint]

Tux Paint 0.9.32 is available!

A number of new tools have been added! Download it today for Windows, macOS, Android, Linux, or Haiku!

⦬ 1-, 2-, and 3-point perspective

Three pairs of new tools provide ways to easily sketch drawings in Tux Paint using 1-, 2-, and 3-point perspective, as well as adjusting the different perspectives' vanishing points. The drawing tools are similar to the Line tool, except only certain angles are possible, based on the position of the line relative to the vanishing points. For example, in 1- and 2-point perspective, lines may be drawn vertically and horizontally, but diagonally they must always be angled toward or away from the vanishing point(s).

🧊Isometric, Dimetric, Trimetric, and Oblique

Another new set of tools provide ways to sketch drawings in an isometric projection, plus two other orthographic projections, dimetric and trimetric, as well as oblique. For the latter three, it's possible to adjust various drawing angles that each tool allows.

🟒Epitrochoid and Hypotrochoid

Two new tools have been added that draw "centered trochoid" curves — patterns created when one circle rolls around the inside or outside of another circle. The resulting shapes are similar to those created by devices such as the Spirograph. The radii of both circles, plus the position of the virtual pen relative to the moving circle, may all be adjusted.

Read more in our press release.

#tuxpaint #tux paint #digital art #open source #software libre #free software #edtech

[millacm]

hey there i heckin love ur art. it's rad. you're rad. thanks for existing.

awwh Thank YOU for saying that and you’re neat for loving my art !!

#ask #epitrochoide

[t4s]

https://en.wikipedia.org/wiki/Epitrochoid

#gif #diagram #blue #red #grid #geometry

[nicksayers]

I enjoyed bringing my toddler bike, suitcase-sized Bicycle Spirograph 4 drawing machine to Bike Boom bike parts jumble sale yesterday. Its first public appearance since the pandemic – in fact, its first proper outing since I made it for two art exhibitions in South Korea in late 2019. My last foreign work trip! Here’s to more art and science adventures in 2022… #GiantDrawingMachines @bikebooom #bigbikejumblesale #drawingmachines #spirograph #epitrochoid #bikeart #geometry #scrapart #recycledart (at Portslade, West Sussex, United Kingdom) https://www.instagram.com/p/CazTKmKIyCj/?utm_medium=tumblr

#giantdrawingmachines #bigbikejumblesale #drawingmachines #spirograph #epitrochoid #bikeart #geometry #scrapart #recycledart

[seat-safety-switch]

Those poor fools who have never driven a rotary car don't get it. When you put your foot down in what is basically a midget jet engine with rabies and listen to that delectable triangle scream, it's hard to imagine that things could get better. That's why they had to add the rev buzzer, because people were having too much fun listening to the revs build and would forget to shift.

For years, I'd been hanging around the periphery of the local epitrochoid-groping community. Those guys would meet up in a Tim Hortons parking lot and discuss premix, oil-metering pumps, oil pump shimming and a lot of other things to do with oil as well. There's a good reason for that: in a rotary, oil pressure is critical. If the oil isn't in the right place in the engine at just the right time, your 15000-rpm nightmare motor will no longer dominate the Mulsanne Straight but instead cough out a shitload of its own special coatings and die.

Now, I'm a bit of an expert in low oil pressure. I just got off the phone with a guy at the Society for Automotive Ignorance who is writing a paper about how long I was able to stretch out an oil change on my old Dart. I figured that there was another option to build and maintain the appropriate amount of oil pressure in a little Mazda RX-7, and that option just happened to be the slightly-damaged Dart 318 I had lying in my driveway.

Sure, the academics will tell you that it's quote-unquote "wasteful" to use a 180-horsepower iron-block American V8 just to pump oil into the 148-horsepower 13B. They might even drag out papers about power-to-weight ratios and pumping losses. Don't be fooled: their opposition to my project originates not in sound science, but in jealousy. And maybe also concern for the large amount of superheated oil I have spraying into my passenger floorboards from the leaking fittings when I get close to redline. At least now I have two ways to remember to upshift.

#mazda rx7 #mazda #dodge #dodge dart

[horsyunicorn]

re: that post about men complicating fields of knowledge such as baking

my nuclear physics textbook could absolutely have been written better. Talking about the motion of a charged particle trapped in a 3D magnetic field, the motion is described as "very complicated and difficult to illustrate... a so-called epitrochoid" and you're left to search for the shape yourself

when they could have just written "an epitrochoid is simply the shape produced by the end of a line extending from the diameter of a circle, that is rolling along the circumference of a larger fixed circle". The shape produced varies on the extension length of that line, and the ratio of the two circles in size, and perhaps it's beyond the scope of the book to spend time describing a shape when its subject matter is nuclear physics, but it does interrupt the flow of reading, and they didn't have to write "very complicated and suit difficult to illustrate". Like, the text is saying "this is the shape" and the subtext is "this subject is difficult to grasp and you should feel inferior for being the reader instead of the author". It's figuratively putting a barrier between the reader and knowledge they're trying to extract from the text. Ugh

[lyssahumana]

Toys From My Childhood:

Spirograph is a geometric drawing toy that produces mathematical roulette curves of the variety technically known as hypotrochoids and epitrochoids. It was developed by British engineer Denys Fisher and first sold in 1965.

The name has been a registered trademark of Hasbro Inc. since 1998 following purchase of the company that had acquired the Denys Fisher company. The Spirograph brand was relaunched worldwide with original product configurations in 2013 by Kahootz Toys.

In 1827 English architect and engineer Peter Hubert Desvignes developed his "Speiragraph",[1] a machine to create elaborate spiral drawings, intended to prevent bank note forgeries.[2]

The mathematician Bruno Abakanowicz invented the Spirograph between 1881 and 1900. It was used for calculating an area delimited by curves.[3] Drawing toys based on gears have been around since at least 1908, when The Marvelous Wondergraph was advertised in the Sears catalog.[4][5] An article describing how to make a Wondergraph drawing machine appeared in the Boys Mechanic publication in 1913.[6] The Spirograph itself was developed by the British engineer Denys Fisher, who exhibited at the 1965 Nuremberg International Toy Fair. It was subsequently produced by his company. US distribution rights were acquired by Kenner, Inc., which introduced it to the United States market in 1966 and promoted it as a creative children's toy.

In 2013 the Spirograph brand was re-launched worldwide by Kahootz Toys with products that returned to the use of the original gears and wheels. The modern products use removable putty in place of pins or are held down by hand to keep the stationary pieces in place on the paper. The Spirograph was a 2014 Toy of the Year finalist in two categories, over 45 years after the toy was named Toy of the Year in 1967. [Wikipedia]

#Toys From My Childhood #toys