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Back in the 1920s, draftspersons and cartographers used a highly specialized tool called a dotting pen to draw absolutely flawless dashed and dotted lines by hand. Instead of a standard nib, this ingenious writing instrument featured a tiny, interchangeable gear wheel attached to the tip. The mechanics were incredibly...

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Mechanical Knowledge

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50,050 次观看 • 1 个月前 •via X (Twitter)

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Here's what the new fake gear shifting sounds and looks like in the 2027 Porsche Taycan. It's called "E-Shift". Porsche: "Drivers can switch between a total of eight simulated gears using paddles on the GT Sport steering wheel. The gear changes are modeled to feel authentic with noticeable gear shift feel, gear-specific drag torque – comparable to the engine braking behavior of a combustion-engined car – and a virtual rev limiter. At the same time, the interior and exterior sound of the Porsche Electric Sport Sound adapts to the respective driving situation depending on the load and wheel speed. The sound tuning varies across the various Taycan derivatives. The system is supplemented by a virtual rev counter and a gear indicator with shift light in the instrument cluster."
1:17

Here's what the new fake gear shifting sounds and looks like in the 2027 Porsche Taycan. It's called "E-Shift". Porsche: "Drivers can switch between a total of eight simulated gears using paddles on the GT Sport steering wheel. The gear changes are modeled to feel authentic with noticeable gear shift feel, gear-specific drag torque – comparable to the engine braking behavior of a combustion-engined car – and a virtual rev limiter. At the same time, the interior and exterior sound of the Porsche Electric Sport Sound adapts to the respective driving situation depending on the load and wheel speed. The sound tuning varies across the various Taycan derivatives. The system is supplemented by a virtual rev counter and a gear indicator with shift light in the instrument cluster."

Sawyer Merritt

890,274 次观看 • 2 个月前

A Breakthrough in Robotics: Spherical Gears Enter Mass Production Spherical gears, the kind of joint that would allow a robot to move like a human shoulder, have been notoriously difficult to manufacture with high precision. That's changing, thanks to a new design and a path to mass production that could have a huge impact on robotics. The breakthrough comes from a new design called the ABENICS spherical gear, developed by researchers at Yamagata University. This innovative mechanism enables a joint to move in three degrees of freedom without the slippage issues of earlier designs. It achieves this by using a "cross-spherical gear" that meshes with one or more "monopole gears." Mass production is now on the horizon. Although the initial manufacturing of the gears was inefficient, Nissei Corporation improved the process and established the necessary technology. The companies Kanematsu and Nissei have now entered the marketing phase, with production expected to begin in 2027. The impact of this technology is significant. Mass-produced spherical gears are expected to enable highly versatile and efficient robotic limbs. ► Humanoid and Mobile Robots: The design allows for compact, high-torque ball joints ideal for creating versatile and efficient robotic limbs. ► Aerospace: Potential applications include deployment mechanisms for satellite solar panels. ► Other Industries: The technology is also being explored for its potential to enhance productivity in healthcare, nursing care, and restaurants.
2:01

A Breakthrough in Robotics: Spherical Gears Enter Mass Production Spherical gears, the kind of joint that would allow a robot to move like a human shoulder, have been notoriously difficult to manufacture with high precision. That's changing, thanks to a new design and a path to mass production that could have a huge impact on robotics. The breakthrough comes from a new design called the ABENICS spherical gear, developed by researchers at Yamagata University. This innovative mechanism enables a joint to move in three degrees of freedom without the slippage issues of earlier designs. It achieves this by using a "cross-spherical gear" that meshes with one or more "monopole gears." Mass production is now on the horizon. Although the initial manufacturing of the gears was inefficient, Nissei Corporation improved the process and established the necessary technology. The companies Kanematsu and Nissei have now entered the marketing phase, with production expected to begin in 2027. The impact of this technology is significant. Mass-produced spherical gears are expected to enable highly versatile and efficient robotic limbs. ► Humanoid and Mobile Robots: The design allows for compact, high-torque ball joints ideal for creating versatile and efficient robotic limbs. ► Aerospace: Potential applications include deployment mechanisms for satellite solar panels. ► Other Industries: The technology is also being explored for its potential to enhance productivity in healthcare, nursing care, and restaurants.

RoboHub🤖

384,888 次观看 • 11 个月前

AIR INDIA 787 ‘thoughts’ I’m surprised nobody, even the experts) have mentioned this… The 787 Dreamliner (all variants) has an ‘Air Ground Sensing’ system that opens the Main Gear doors immediately upon leaving the runway and prior to the (Flight Deck) Lever being moved manually to the ‘up’ position. I’ve witnessed this literally hundreds of times when filming The 787 and it’s clear on the footage attached: upon rotate, about one second from wheels off ground, the main Gear Doors open. Then, around three to four seconds (pilot discretion) Positive Rate is called/agreed and the Gear Lever is moved to the UP position. On a side note, the 787 is quite prone to brake malfunction, mostly down to the electric brake system that can fail from time to time on a single (or more) wheel. If the wheels are not retracted within a given amount of time due to a wheel continuing to spin, the gear doors will close back-up until the wheel(s) stop spinning and the gear is recycled at which time the doors will re-open and the gear will retract fully. This is the takeoff/gear-up procedure with all 787s. This is quite clearly not the case when observing the CCTV footage of the doomed Air India jet. I think it’s quite evident there was some kind of (electrical?) malfunction with the system(s). The question of the Flap (takeoff) Setting is still a mystery as, with poor quality footage, it’s difficult to completely confirm whether the flaps were extended or not. In my personal opinion they were not extended. There was a CNN reporter right next to one of the wings on the ground. Although it was heavily charred, it would’ve been clear to see if they were extended or not 🤷🏼‍♂️ Also, as for possible (engine) ingestion/failure, whether by birds or other FOD, there is no evidence of engine Compressor Stall, which is very clear to see in many videos online when it does happen with bird strikes, especially at rotate power/speed. The engine(s) will ‘pop’ flames out of the back. What is evident, is that the Jet uses all of the available runway, which is clear by the amount of dust being kicked-up on rotate. The Jet never seems to reach the optimal takeoff angle, right from the rotate point it appears to struggle, which would suggest either engine power issues or, as mentioned, the lack of lift from the Flaps/Slats. Witness accounts say there was a distinct lack of engine noise coming from the jet, which backs-up some theories of engine failure. You would expect, even with a lack of Flap setting the pilot would be able to increase to max (TOGA) power to give them some chance of climbing or at least gaining enough altitude to get themselves back to the airfield or to a safer (crash) landing zone. That ‘power up’ would be evident with black exhaust from the engines, but that didn’t happen - at all. You’ll see/hear from the (second part) footage I’ve filmed, that the engine sound is very evident at this height and that this climb-out is too Standard Operating Procedures. Personally I find it hard to believe the NFP would make such a rookie mistake as to raise the flaps (push and move the staggered lever) as opposed to the gear lever which is a simple up-down motion. The two levers are also in completely different positions: Gear lever on the facing panel and flap lever (with many settings) next to the throttles. Plus this is such a basic procedure that even the most rookie pilot wouldn’t make this mistake 🤷🏼‍♂️ Again, this is just my opinion and observations based on visual and actual experiences. The CVR and FDR will deliver the final evidence.
1:21

AIR INDIA 787 ‘thoughts’ I’m surprised nobody, even the experts) have mentioned this… The 787 Dreamliner (all variants) has an ‘Air Ground Sensing’ system that opens the Main Gear doors immediately upon leaving the runway and prior to the (Flight Deck) Lever being moved manually to the ‘up’ position. I’ve witnessed this literally hundreds of times when filming The 787 and it’s clear on the footage attached: upon rotate, about one second from wheels off ground, the main Gear Doors open. Then, around three to four seconds (pilot discretion) Positive Rate is called/agreed and the Gear Lever is moved to the UP position. On a side note, the 787 is quite prone to brake malfunction, mostly down to the electric brake system that can fail from time to time on a single (or more) wheel. If the wheels are not retracted within a given amount of time due to a wheel continuing to spin, the gear doors will close back-up until the wheel(s) stop spinning and the gear is recycled at which time the doors will re-open and the gear will retract fully. This is the takeoff/gear-up procedure with all 787s. This is quite clearly not the case when observing the CCTV footage of the doomed Air India jet. I think it’s quite evident there was some kind of (electrical?) malfunction with the system(s). The question of the Flap (takeoff) Setting is still a mystery as, with poor quality footage, it’s difficult to completely confirm whether the flaps were extended or not. In my personal opinion they were not extended. There was a CNN reporter right next to one of the wings on the ground. Although it was heavily charred, it would’ve been clear to see if they were extended or not 🤷🏼‍♂️ Also, as for possible (engine) ingestion/failure, whether by birds or other FOD, there is no evidence of engine Compressor Stall, which is very clear to see in many videos online when it does happen with bird strikes, especially at rotate power/speed. The engine(s) will ‘pop’ flames out of the back. What is evident, is that the Jet uses all of the available runway, which is clear by the amount of dust being kicked-up on rotate. The Jet never seems to reach the optimal takeoff angle, right from the rotate point it appears to struggle, which would suggest either engine power issues or, as mentioned, the lack of lift from the Flaps/Slats. Witness accounts say there was a distinct lack of engine noise coming from the jet, which backs-up some theories of engine failure. You would expect, even with a lack of Flap setting the pilot would be able to increase to max (TOGA) power to give them some chance of climbing or at least gaining enough altitude to get themselves back to the airfield or to a safer (crash) landing zone. That ‘power up’ would be evident with black exhaust from the engines, but that didn’t happen - at all. You’ll see/hear from the (second part) footage I’ve filmed, that the engine sound is very evident at this height and that this climb-out is too Standard Operating Procedures. Personally I find it hard to believe the NFP would make such a rookie mistake as to raise the flaps (push and move the staggered lever) as opposed to the gear lever which is a simple up-down motion. The two levers are also in completely different positions: Gear lever on the facing panel and flap lever (with many settings) next to the throttles. Plus this is such a basic procedure that even the most rookie pilot wouldn’t make this mistake 🤷🏼‍♂️ Again, this is just my opinion and observations based on visual and actual experiences. The CVR and FDR will deliver the final evidence.

BIG JET TV

1,728,608 次观看 • 1 年前

Why the 737 landing gear lever has an “OFF” position ✈️ It’s a question I get asked quite often and understandably so! “OFF” isn’t a logical position for the landing gear! The landing gear is retracted into the belly of the aircraft using hydraulic pressure. Once the gear is fully up, mechanical uplocks hold the gear safely in position. However, with the lever in the UP position, hydraulic pressure is still being applied to the system. This is unnecessary now that the gear is being held up with mechanical latches and places extra demand in the hydraulic pumps. So, once the gear has been retracted, the pilots will move the gear lever from UP to OFF as part of the after takeoff checklist. This simply removes hydraulic pressure from the retract lines. When the pilots configure the aircraft for landing, we move the landing gear lever from OFF to DOWN. This action releases the mechanical up locks and the gear is lowered using a combination of hydraulic pressure, gravity and air loads. Once the gear is fully down and locked, a green light - one for each set of wheels, will illuminate. Should the primary gear down sensors fail, we have a second set of green, gear down indicators on the overhead panel. As long as the gear is indicating down and locked on either the primary or standby indicator, the gear is down and locked and safe to land on 👍 In the very unlikely event that the gear won’t lower normally using the landing gear lever, we have a standby gear lowering system which allows the crew to manually release the gear uplocks and allow gravity to lower the gear - see my reel showing that system in operation . With airlinepilotperformance
1:17

Why the 737 landing gear lever has an “OFF” position ✈️ It’s a question I get asked quite often and understandably so! “OFF” isn’t a logical position for the landing gear! The landing gear is retracted into the belly of the aircraft using hydraulic pressure. Once the gear is fully up, mechanical uplocks hold the gear safely in position. However, with the lever in the UP position, hydraulic pressure is still being applied to the system. This is unnecessary now that the gear is being held up with mechanical latches and places extra demand in the hydraulic pumps. So, once the gear has been retracted, the pilots will move the gear lever from UP to OFF as part of the after takeoff checklist. This simply removes hydraulic pressure from the retract lines. When the pilots configure the aircraft for landing, we move the landing gear lever from OFF to DOWN. This action releases the mechanical up locks and the gear is lowered using a combination of hydraulic pressure, gravity and air loads. Once the gear is fully down and locked, a green light - one for each set of wheels, will illuminate. Should the primary gear down sensors fail, we have a second set of green, gear down indicators on the overhead panel. As long as the gear is indicating down and locked on either the primary or standby indicator, the gear is down and locked and safe to land on 👍 In the very unlikely event that the gear won’t lower normally using the landing gear lever, we have a standby gear lowering system which allows the crew to manually release the gear uplocks and allow gravity to lower the gear - see my reel showing that system in operation . With airlinepilotperformance

aircraftmaintenancengineer

19,786 次观看 • 1 个月前

The Berlin Secretary Cabinet, crafted by David Roentgen in 1779, stands as a pinnacle of 18th-century European furniture design. This exquisite writing cabinet, crowned with a chiming clock, showcases intricate marquetry and sophisticated mechanical features that allow doors and drawers to open at the touch of a button. Originally acquired by King Frederick William II of Prussia, the cabinet reflects the monarch’s appreciation for fine craftsmanship and innovative design. Today, this remarkable piece is housed in the Kunstgewerbemuseum, Staatliche Museen zu Berlin, where it continues to captivate visitors with its blend of artistry and engineering.
0:58

The Berlin Secretary Cabinet, crafted by David Roentgen in 1779, stands as a pinnacle of 18th-century European furniture design. This exquisite writing cabinet, crowned with a chiming clock, showcases intricate marquetry and sophisticated mechanical features that allow doors and drawers to open at the touch of a button. Originally acquired by King Frederick William II of Prussia, the cabinet reflects the monarch’s appreciation for fine craftsmanship and innovative design. Today, this remarkable piece is housed in the Kunstgewerbemuseum, Staatliche Museen zu Berlin, where it continues to captivate visitors with its blend of artistry and engineering.

History Photographed

65,785 次观看 • 1 年前

The method Randall describes is elegant in its simplicity and profound in its implications. Drive a pole with a sharpened point into the ground. Draw a circle of any sacred length around it. As the sun rises in the east, a long shadow is cast to the west - and as it shortens toward noon, the moment the shadow's tip touches the circle, a stake is driven into the ground. That point is due south. As the afternoon progresses and the shadow swings back and lengthens toward the west, a second stake is driven when the tip touches the circle again. String a line between the two stakes and the result is a precise east-west line. The north-south axis follows immediately from there. With those four cardinal directions established, the entire geometric program of a sacred site can be laid out - squares, rectangles, circles, ellipses, all derived from a single pole, a drawn circle, and the movement of the sun across the sky. No instruments beyond what any culture in any era could produce. No calculations beyond what sustained observation of shadow movement provides. Randall's point is that this method was available to every ancient builder who ever oriented a monument to the cardinal directions - and the precision of the sacred sites that resulted was not the product of sophisticated technology but of a simple, reproducible technique that anyone willing to watch the sun carefully enough could master.
1:10

The method Randall describes is elegant in its simplicity and profound in its implications. Drive a pole with a sharpened point into the ground. Draw a circle of any sacred length around it. As the sun rises in the east, a long shadow is cast to the west - and as it shortens toward noon, the moment the shadow's tip touches the circle, a stake is driven into the ground. That point is due south. As the afternoon progresses and the shadow swings back and lengthens toward the west, a second stake is driven when the tip touches the circle again. String a line between the two stakes and the result is a precise east-west line. The north-south axis follows immediately from there. With those four cardinal directions established, the entire geometric program of a sacred site can be laid out - squares, rectangles, circles, ellipses, all derived from a single pole, a drawn circle, and the movement of the sun across the sky. No instruments beyond what any culture in any era could produce. No calculations beyond what sustained observation of shadow movement provides. Randall's point is that this method was available to every ancient builder who ever oriented a monument to the cardinal directions - and the precision of the sacred sites that resulted was not the product of sophisticated technology but of a simple, reproducible technique that anyone willing to watch the sun carefully enough could master.

Randall Carlson

142,043 次观看 • 5 个月前

Before “hacking” had a name, it had a cereal prize. General Mills slipped a tiny plastic whistle into Cap’n Crunch boxes in the late ’60s. Turns out, that toy chirped at 2600 Hz — the exact tone AT&T used to signal “this trunk line is open.” Kids (and a few very curious adults) discovered you could blow the whistle into a payphone and… the system would politely hand you a free long-distance line. It was the golden age of phone phreaking — equal parts mischief, curiosity, and accidental engineering lesson. One of the young people fascinated by this loophole? Steve Jobs. He later said that if it weren’t for blue boxes and cereal whistles, Apple might never have happened. A toy in a cereal box became a backdoor into the most advanced network in the world. Have you heard this story — or were you lucky enough to own a Cap’n Crunch whistle?
1:44

Before “hacking” had a name, it had a cereal prize. General Mills slipped a tiny plastic whistle into Cap’n Crunch boxes in the late ’60s. Turns out, that toy chirped at 2600 Hz — the exact tone AT&T used to signal “this trunk line is open.” Kids (and a few very curious adults) discovered you could blow the whistle into a payphone and… the system would politely hand you a free long-distance line. It was the golden age of phone phreaking — equal parts mischief, curiosity, and accidental engineering lesson. One of the young people fascinated by this loophole? Steve Jobs. He later said that if it weren’t for blue boxes and cereal whistles, Apple might never have happened. A toy in a cereal box became a backdoor into the most advanced network in the world. Have you heard this story — or were you lucky enough to own a Cap’n Crunch whistle?

TheRealCherokeeOwl 🦉

71,982 次观看 • 6 个月前

Why did Ian Whiffin agree to give expert testimony on Jen McCabe’s cellphone extraction, when the state refused to let him look at or even give him the full, original extraction OR its verification hash? A thread🧵 Full cellphone extractions, sometimes called forensic images, generate what’s called a “hash value”, which serves as a unique digital fingerprint necessary for ensuring the integrity of data. Any discrepancy between the hash values indicates tampering with or corruption of evidence, alerting forensic examiners to potential issues with the evidence. Hash verification is a fundamental principle and a rather ubiquitous practice in the world of digital forensics, where data validation and verification are key. It is the gold standard across the industry, and has also become so in the courtroom, whereby admissibility of digital evidence is determined by its relevance, authenticity and reliability. In court, the hash value can be used to demonstrate that the evidence has not been altered since its collection, and is a universal way for experts to authenticate and validate the reliability of data for the trial Court. But, an extraction that’s missing a hash value altogether is a huge red flag. 🚩 Who removed the hash value? And why? It’s necessary to the chain of custody, and as Gaurino and Tully would be well aware, it’s also an element of the data that an expert would require in order to verify and validate it. There’s no “good” reason for why someone would remove a hash value, and the extraction can’t be characterized as a forensic image as its origin is unknown. This was a deliberate step taken to hide something, which one could argue shows consciousness of guilt. If the data are true and accurate, why would you bring their integrity into question by removing the hash? However, if the data were altered or tampered with, and let’s say, hypothetically speaking, you wanted a digital forensic expert to provide testimony supportive of your “Google search” theory. . . In that hypothetical, you’d have to remove the hash value. Otherwise, the expert would immediately detect that the data were altered, as they would not be able to verify the hash against the original. #KarenReadTrial #JusticeForJohnOKeefe #FreeKarenRead #CantonCoverup #PoliceCorruption #KarenRead #Cellebrite #DFIR
0:23

Why did Ian Whiffin agree to give expert testimony on Jen McCabe’s cellphone extraction, when the state refused to let him look at or even give him the full, original extraction OR its verification hash? A thread🧵 Full cellphone extractions, sometimes called forensic images, generate what’s called a “hash value”, which serves as a unique digital fingerprint necessary for ensuring the integrity of data. Any discrepancy between the hash values indicates tampering with or corruption of evidence, alerting forensic examiners to potential issues with the evidence. Hash verification is a fundamental principle and a rather ubiquitous practice in the world of digital forensics, where data validation and verification are key. It is the gold standard across the industry, and has also become so in the courtroom, whereby admissibility of digital evidence is determined by its relevance, authenticity and reliability. In court, the hash value can be used to demonstrate that the evidence has not been altered since its collection, and is a universal way for experts to authenticate and validate the reliability of data for the trial Court. But, an extraction that’s missing a hash value altogether is a huge red flag. 🚩 Who removed the hash value? And why? It’s necessary to the chain of custody, and as Gaurino and Tully would be well aware, it’s also an element of the data that an expert would require in order to verify and validate it. There’s no “good” reason for why someone would remove a hash value, and the extraction can’t be characterized as a forensic image as its origin is unknown. This was a deliberate step taken to hide something, which one could argue shows consciousness of guilt. If the data are true and accurate, why would you bring their integrity into question by removing the hash? However, if the data were altered or tampered with, and let’s say, hypothetically speaking, you wanted a digital forensic expert to provide testimony supportive of your “Google search” theory. . . In that hypothetical, you’d have to remove the hash value. Otherwise, the expert would immediately detect that the data were altered, as they would not be able to verify the hash against the original. #KarenReadTrial #JusticeForJohnOKeefe #FreeKarenRead #CantonCoverup #PoliceCorruption #KarenRead #Cellebrite #DFIR

Olivia

270,376 次观看 • 1 年前

“No architecture is so haughty as that which is simple; which refuses to address the eye, except in a few clear and forceful lines; which implies, in offering so little to our regards, that all it has offered is perfect; and disdains, either by the complexity or the attractiveness of its features, to embarrass our investigation, or betray us into delight.” - John Ruskin, The Stones of Venice
0:22

“No architecture is so haughty as that which is simple; which refuses to address the eye, except in a few clear and forceful lines; which implies, in offering so little to our regards, that all it has offered is perfect; and disdains, either by the complexity or the attractiveness of its features, to embarrass our investigation, or betray us into delight.” - John Ruskin, The Stones of Venice

The War on Beauty

11,495 次观看 • 6 个月前

As requested by Alex Miller yesterday, a look at our out of possession shape in the first half. 1: (10 secs) - Wednesday in a very narrow high block in a 523 out of possession. It only looked like this when the ball is central. Nowrich rotate (change positions during play) a lot and this narrow block denies central rotation. In this clip, they have had rotation in left back position as the CM has dropped into the area and left back on the last line. 2: 20 secs - When the ball went wide or started to move wide, the full back would advance up the pitch to pressure the full back and press full back to full back, whilst the CBs would come out with the Norwich forwards coming in between the lines, as this ball transitions across the pitch you see Sargent come out and Iorfa following tight. Fusire in this clip has come out to mark full back to full back and creating a makeshift back 4. 3: 47 secs - Wednesday get back into their narrow block shape 4: 56 secs - rotation from the front line form Norwich 5: 58 seconds, Palmer comes out of the back line to pick up the rotation and prevent space between lines. As the player turns to our left, Amass starts to come out to pick up full back to full back on the other side. In summary, Wednesday played their familiar 523 blocking shape out of possession but it was much more proactive in the back 5 than we usually see it, with full backs and Cbs following rotations and stepping out of the backline to prevent space between lines. It worked, first half. Norwich combated it a little better second half. Will get a clip out tomorrow of what they did
1:39

As requested by Alex Miller yesterday, a look at our out of possession shape in the first half. 1: (10 secs) - Wednesday in a very narrow high block in a 523 out of possession. It only looked like this when the ball is central. Nowrich rotate (change positions during play) a lot and this narrow block denies central rotation. In this clip, they have had rotation in left back position as the CM has dropped into the area and left back on the last line. 2: 20 secs - When the ball went wide or started to move wide, the full back would advance up the pitch to pressure the full back and press full back to full back, whilst the CBs would come out with the Norwich forwards coming in between the lines, as this ball transitions across the pitch you see Sargent come out and Iorfa following tight. Fusire in this clip has come out to mark full back to full back and creating a makeshift back 4. 3: 47 secs - Wednesday get back into their narrow block shape 4: 56 secs - rotation from the front line form Norwich 5: 58 seconds, Palmer comes out of the back line to pick up the rotation and prevent space between lines. As the player turns to our left, Amass starts to come out to pick up full back to full back on the other side. In summary, Wednesday played their familiar 523 blocking shape out of possession but it was much more proactive in the back 5 than we usually see it, with full backs and Cbs following rotations and stepping out of the backline to prevent space between lines. It worked, first half. Norwich combated it a little better second half. Will get a clip out tomorrow of what they did

TW Football

16,673 次观看 • 9 个月前

The Polyphon: When Music Was Programmed on Perforated Discs In the closing years of the 19th century, long before vinyl records, magnetic tape, or digital files, a remarkable machine let ordinary people summon complex, multi-note music from thin air. It did not play recordings of real instruments or voices. Instead, it executed precise mechanical instructions encoded on interchangeable metal discs. That machine was the Polyphon, and its story is one of the earliest and most elegant examples of “software” for music. The Polyphon was invented in 1870 in Leipzig, Germany, by two engineers: Gustav Adolf Brachhausen and Ernst Paul Riessner. They had previously worked with the Symphonion company, which had pioneered commercial disc-playing music boxes in the mid-1880s. Brachhausen and Riessner broke away to perfect and commercialize their own version. Their firm, originally called Firma Brachhausen & Riesener, was founded in 1887 in the Leipzig suburb of Wahren. It was renamed Polyphon-Musikwerke AG in 1895, and full-scale production of the iconic disc machines began around 1896–1897. The timing was perfect. Traditional cylinder music boxes, with their pinned barrels, were beautiful but expensive to make and difficult to duplicate in volume. Each new tune required an entirely new cylinder. The disc system changed everything. A single machine could play dozens or hundreds of different pieces simply by swapping a disc. This was revolutionary it turned music into something you could collect, trade, and update, much like software libraries or app catalogs today. Polyphon machines and their discs were exported worldwide. In 1892 the company sent people and tooling to America to establish the Regina Music Box Company in Rahway, New Jersey. Regina became one of the most famous names in American disc boxes and helped popularize the format across the Atlantic. How the Polyphon Actually Worked At first glance, a Polyphon looks like an ornate wooden cabinet or tabletop box with a large, flat metal disc inside. Wind the powerful clockwork motor (or, on coin-operated models, drop a coin), and the disc begins to spin. The magic is in the disc itself. These are not simple records. They are precision-stamped or punched sheets of tin-plated steel or similar metal. During manufacturing, holes are punched in carefully arranged patterns. The displaced metal is curled or pressed downward to form small raised projections — called plectra — on the underside of the disc. These tiny “fingers” are the actual data. As the disc rotates: The projections engage a row of star wheels (small, multi-pointed ratchets mounted in a gantry above the comb). Each star wheel is nudged forward by a projection and rotates just enough to pluck one tooth on the musical comb — a precisely tuned set of steel teeth of varying lengths. Longer teeth produce lower (bass) notes; shorter teeth produce higher (treble) notes. The radial position of the hole on the disc determines pitch; its angular position determines timing. Many models used two combs (sometimes striking simultaneously for richer tone, sometimes alternately). Larger instruments could have impressive volume and harmonic complexity. Playing time for a typical large disc (around 19–20 inches / 50 cm) was roughly 1 minute 45 seconds to 2 minutes — enough for a complete popular song, march, or waltz of the era. Drive systems varied by size. Smaller discs often used a center spindle; larger ones used peripheral drive holes around the edge for better stability and torque. A pressure bar kept the disc flat and properly engaged with the star wheels. Where the Polyphon becomes truly fascinating from a technological history perspective: The perforated disc is not a recording. It is a program. It contains encoded instructions: “At this moment, pluck these specific notes in this sequence and combination.” Change the disc, and the machine plays an entirely different piece without any modification.
0:58

The Polyphon: When Music Was Programmed on Perforated Discs In the closing years of the 19th century, long before vinyl records, magnetic tape, or digital files, a remarkable machine let ordinary people summon complex, multi-note music from thin air. It did not play recordings of real instruments or voices. Instead, it executed precise mechanical instructions encoded on interchangeable metal discs. That machine was the Polyphon, and its story is one of the earliest and most elegant examples of “software” for music. The Polyphon was invented in 1870 in Leipzig, Germany, by two engineers: Gustav Adolf Brachhausen and Ernst Paul Riessner. They had previously worked with the Symphonion company, which had pioneered commercial disc-playing music boxes in the mid-1880s. Brachhausen and Riessner broke away to perfect and commercialize their own version. Their firm, originally called Firma Brachhausen & Riesener, was founded in 1887 in the Leipzig suburb of Wahren. It was renamed Polyphon-Musikwerke AG in 1895, and full-scale production of the iconic disc machines began around 1896–1897. The timing was perfect. Traditional cylinder music boxes, with their pinned barrels, were beautiful but expensive to make and difficult to duplicate in volume. Each new tune required an entirely new cylinder. The disc system changed everything. A single machine could play dozens or hundreds of different pieces simply by swapping a disc. This was revolutionary it turned music into something you could collect, trade, and update, much like software libraries or app catalogs today. Polyphon machines and their discs were exported worldwide. In 1892 the company sent people and tooling to America to establish the Regina Music Box Company in Rahway, New Jersey. Regina became one of the most famous names in American disc boxes and helped popularize the format across the Atlantic. How the Polyphon Actually Worked At first glance, a Polyphon looks like an ornate wooden cabinet or tabletop box with a large, flat metal disc inside. Wind the powerful clockwork motor (or, on coin-operated models, drop a coin), and the disc begins to spin. The magic is in the disc itself. These are not simple records. They are precision-stamped or punched sheets of tin-plated steel or similar metal. During manufacturing, holes are punched in carefully arranged patterns. The displaced metal is curled or pressed downward to form small raised projections — called plectra — on the underside of the disc. These tiny “fingers” are the actual data. As the disc rotates: The projections engage a row of star wheels (small, multi-pointed ratchets mounted in a gantry above the comb). Each star wheel is nudged forward by a projection and rotates just enough to pluck one tooth on the musical comb — a precisely tuned set of steel teeth of varying lengths. Longer teeth produce lower (bass) notes; shorter teeth produce higher (treble) notes. The radial position of the hole on the disc determines pitch; its angular position determines timing. Many models used two combs (sometimes striking simultaneously for richer tone, sometimes alternately). Larger instruments could have impressive volume and harmonic complexity. Playing time for a typical large disc (around 19–20 inches / 50 cm) was roughly 1 minute 45 seconds to 2 minutes — enough for a complete popular song, march, or waltz of the era. Drive systems varied by size. Smaller discs often used a center spindle; larger ones used peripheral drive holes around the edge for better stability and torque. A pressure bar kept the disc flat and properly engaged with the star wheels. Where the Polyphon becomes truly fascinating from a technological history perspective: The perforated disc is not a recording. It is a program. It contains encoded instructions: “At this moment, pluck these specific notes in this sequence and combination.” Change the disc, and the machine plays an entirely different piece without any modification.

Brian Roemmele

30,233 次观看 • 3 个月前

Clutch install hack that is a massive time saver. The struggle of balancing a clutch disc and pressure plate while lying on your back is a rite of passage for every person that ever tried this install—but it doesn’t have to be a struggle. ​If you’ve ever lost your alignment tool or find yourself working on a platform where the tool just won't stay seated, this zip-tie hack is your best friend. By "marrying" the disc to the pressure plate before you lift it into place, you’re essentially creating a single unit. ​Why this works: ​Perfect Centering: The ties keep the disc from sagging, ensuring it lines up perfectly with the pilot bearing. ​Weight Distribution: It’s much easier to handle one solid unit than two sliding plates. ​Solo Friendly: If you don't have a second set of hands, this is a lifesaver. ​Once you’ve got a couple of bolts started into the flywheel, just snip the ties, pull them through, and torque everything down to spec. It’s simple, it’s effective, and it costs about $0.05 in materials. ​Drop a "🔥" if you’ve used this before, or let me know your favorite shop hack in the comments!
1:16

Clutch install hack that is a massive time saver. The struggle of balancing a clutch disc and pressure plate while lying on your back is a rite of passage for every person that ever tried this install—but it doesn’t have to be a struggle. ​If you’ve ever lost your alignment tool or find yourself working on a platform where the tool just won't stay seated, this zip-tie hack is your best friend. By "marrying" the disc to the pressure plate before you lift it into place, you’re essentially creating a single unit. ​Why this works: ​Perfect Centering: The ties keep the disc from sagging, ensuring it lines up perfectly with the pilot bearing. ​Weight Distribution: It’s much easier to handle one solid unit than two sliding plates. ​Solo Friendly: If you don't have a second set of hands, this is a lifesaver. ​Once you’ve got a couple of bolts started into the flywheel, just snip the ties, pull them through, and torque everything down to spec. It’s simple, it’s effective, and it costs about $0.05 in materials. ​Drop a "🔥" if you’ve used this before, or let me know your favorite shop hack in the comments!

Chuckling Charlie

41,665 次观看 • 4 个月前

A simple CNC machine. Wood. A rotating tool. And yet the pattern shifts from circles to perfect hexagons with a level of accuracy most factories still struggle to hit. I worked five years in manufacturing at Siemens, and this is the part people often overlook. The real magic is not new or loud. It is stability. Repeatability. Tool paths that were tuned forever. Precision that just keeps working. Robotics is in a hype cycle right now, but manufacturing has delivered quiet perfection long before anyone talked about foundation models. Sometimes the most interesting engineering is the part that does not ask for attention. —- Weekly robotics and AI insights. Subscribe free:
0:26

A simple CNC machine. Wood. A rotating tool. And yet the pattern shifts from circles to perfect hexagons with a level of accuracy most factories still struggle to hit. I worked five years in manufacturing at Siemens, and this is the part people often overlook. The real magic is not new or loud. It is stability. Repeatability. Tool paths that were tuned forever. Precision that just keeps working. Robotics is in a hype cycle right now, but manufacturing has delivered quiet perfection long before anyone talked about foundation models. Sometimes the most interesting engineering is the part that does not ask for attention. —- Weekly robotics and AI insights. Subscribe free:

Ilir Aliu

164,829 次观看 • 9 个月前

The Fotoplayer was an instrument developed by the American Photo Player Co. between the years of 1912 and 1925, used to provide music and sound effects for silent movies. Before movies had sound, playing background music during a film aided in developing a particular mood for a certain scene. Initially, small theatres would use player pianos to produce music automatically from piano rolls. After some time, some of these pianos were extended in size with pipe organs and sound effects inserted into large cabinets connected to the sides of the piano. The user of this new contraption could then create multiple sounds to match the actions on screen. Between 8,000 and 12,000 of these musical instruments were made between 1910 and 1928. The appeal of the Fotoplayer to theatre owners was the fact that it took no major musical skill to operate. The Fotoplayer would play the piano and pipe organ mechanically using an electric motor, an air pump, and piano rolls while the user of the Fotoplayer would follow the onscreen action while pulling cords, pushing buttons, and pressing pedals to produce relatable sounds to what was occurring onscreen.
1:00

The Fotoplayer was an instrument developed by the American Photo Player Co. between the years of 1912 and 1925, used to provide music and sound effects for silent movies. Before movies had sound, playing background music during a film aided in developing a particular mood for a certain scene. Initially, small theatres would use player pianos to produce music automatically from piano rolls. After some time, some of these pianos were extended in size with pipe organs and sound effects inserted into large cabinets connected to the sides of the piano. The user of this new contraption could then create multiple sounds to match the actions on screen. Between 8,000 and 12,000 of these musical instruments were made between 1910 and 1928. The appeal of the Fotoplayer to theatre owners was the fact that it took no major musical skill to operate. The Fotoplayer would play the piano and pipe organ mechanically using an electric motor, an air pump, and piano rolls while the user of the Fotoplayer would follow the onscreen action while pulling cords, pushing buttons, and pressing pedals to produce relatable sounds to what was occurring onscreen.

Time Capsule Tales

127,558 次观看 • 2 年前

Capoeira is a Brazilian martial art that combines elements of dance, acrobatics, and music. It was practiced by enslaved Africans in Brazil at the beginning of the 16th century. Capoeira originated within as a product of the Angolan tradition of "Engolo" but became applied as a method of survival that was known to slaves. It was a tool with which an escaped slave, completely unequipped, could survive in the hostile, unknown land and face the hunt of the capitães-do-mato, the armed and mounted colonial agents who were charged with finding and capturing escapees. Though tolerated until the 1800s, this quickly became criminalized after due to its association with being African, as well as a threat to the current ruling regime. By the 1920s, capoeira repression had declined, and some physical educators and martial artists started to incorporate capoeira as either a fighting style or a gymnastic method
2:18

Capoeira is a Brazilian martial art that combines elements of dance, acrobatics, and music. It was practiced by enslaved Africans in Brazil at the beginning of the 16th century. Capoeira originated within as a product of the Angolan tradition of "Engolo" but became applied as a method of survival that was known to slaves. It was a tool with which an escaped slave, completely unequipped, could survive in the hostile, unknown land and face the hunt of the capitães-do-mato, the armed and mounted colonial agents who were charged with finding and capturing escapees. Though tolerated until the 1800s, this quickly became criminalized after due to its association with being African, as well as a threat to the current ruling regime. By the 1920s, capoeira repression had declined, and some physical educators and martial artists started to incorporate capoeira as either a fighting style or a gymnastic method

Kentah Gwanjez

17,284 次观看 • 4 个月前

Truly, Our ancestors had a profound way of dealing with P.T.S.D. It was believed that after a war when a man had returned from war, before he could be accepted back into society. He had to live with an Herbalist for 3 months to do some spiritual cleansing. It was said that after war, the human spirit was off balance and required to undergo some ritual in order to restore it back in harmony with nature and the community. A horn was used to draw out stagnant and dsyfunctional blood to the surface. This is one of the ritual that was performed on the worriors to cleanse them of any mental illness and trauma that they might experience later on in life after the war. This process was carried out by Africans long ago before it was allegedly deemed a Chinese invention. It was called "African suction cup," by the colonizers. This is one of the many practices that have been lost due to African s.lavery and colonization. #Africa
0:54

Truly, Our ancestors had a profound way of dealing with P.T.S.D. It was believed that after a war when a man had returned from war, before he could be accepted back into society. He had to live with an Herbalist for 3 months to do some spiritual cleansing. It was said that after war, the human spirit was off balance and required to undergo some ritual in order to restore it back in harmony with nature and the community. A horn was used to draw out stagnant and dsyfunctional blood to the surface. This is one of the ritual that was performed on the worriors to cleanse them of any mental illness and trauma that they might experience later on in life after the war. This process was carried out by Africans long ago before it was allegedly deemed a Chinese invention. It was called "African suction cup," by the colonizers. This is one of the many practices that have been lost due to African s.lavery and colonization. #Africa

Typical African

700,036 次观看 • 2 年前

Someone took this challenge very seriously. Programmers were asked to design the worst user experience imaginable, and apparently some of them approached it with the dedication of a Nobel Prize project. The goal was to make software confusing, frustrating, and almost impossible to use. Mission accomplished. And that is exactly what makes it so entertaining, because by exaggerating everything wrong with bad design, these creations become a perfect parody of user experience gone horribly wrong. The uncomfortable part is that after looking at a few of them, I started recognizing features from real workplace tools. At some point, parody and enterprise software become difficult to tell apart. Which workplace tool have you used that feels like it was designed for this challenge? #Productivity #UserExperience #DigitalWorkplace #WorkplaceHumor
0:40

Someone took this challenge very seriously. Programmers were asked to design the worst user experience imaginable, and apparently some of them approached it with the dedication of a Nobel Prize project. The goal was to make software confusing, frustrating, and almost impossible to use. Mission accomplished. And that is exactly what makes it so entertaining, because by exaggerating everything wrong with bad design, these creations become a perfect parody of user experience gone horribly wrong. The uncomfortable part is that after looking at a few of them, I started recognizing features from real workplace tools. At some point, parody and enterprise software become difficult to tell apart. Which workplace tool have you used that feels like it was designed for this challenge? #Productivity #UserExperience #DigitalWorkplace #WorkplaceHumor

Pascal Bornet

89,159 次观看 • 2 个月前

Jodie Foster says "F1 was made by AI" in a dig at the racing film's script and acting. Director Joseph Kosinski famously went to painstaking lengths to film its stunts and races with practical effects and specially-designed camera rigs. "I don't say this disparagingly, how could I? This movie went on to make millions of dollars. But... the structure was exactly the structure that you would learn in school. The actors say the lines exactly the way it would be written if a computer was writing exactly what would be the right thing for that time. And they were able to dominate the technology to make something big and beautiful and, potentially, where a lot of the information comes from other places."
1:27

Jodie Foster says "F1 was made by AI" in a dig at the racing film's script and acting. Director Joseph Kosinski famously went to painstaking lengths to film its stunts and races with practical effects and specially-designed camera rigs. "I don't say this disparagingly, how could I? This movie went on to make millions of dollars. But... the structure was exactly the structure that you would learn in school. The actors say the lines exactly the way it would be written if a computer was writing exactly what would be the right thing for that time. And they were able to dominate the technology to make something big and beautiful and, potentially, where a lot of the information comes from other places."

Breitbart News

191,049 次观看 • 1 个月前