Engineering

Hello all. 240VAC motors being "overhead" rated : A 20 HP capable motor or a 10 HP capable motor or a 5 HP capable motor driving a machine that demands just 2 HP to perform well (elevator, pump, compressor, whatever...) will any motor fitted consume nearly the same power/energy 'X' ? If the electrical supply is reduced to 120VAC instead for those 240VAC motors and the driven machine demand is still met performing equally fine, will any motor fitted consume nearly the same power/energy 'X' ?

I thought this was interesting: https://www.bbc.co.uk/news/articles/c2l7ry7zp5po The run was a bit artificial, in that they ran the train at ~40mph rather than its top speed of 60mph, but I think it has to be seen as a proof-of-concept demonstration for the public (and doubtless for the politicians who may need to come up with funds to build battery trains and install charging equipment.) The idea is for GWR eventually to replace its ageing diesel multiple units, used for local start-stop services on non-electrified branch lines, with battery trains. This train is very familiar to Londoners like me, as it is converted from a withdrawn District Line Underground train. It n…

I'm getting that feeling myself, having just tried to explain to a guy at Richer Sounds that I want to find a way of getting a wireless connection between my amp and a pair of remote speakers that I want to put in my kitchen. I don't think he has grasped that these speakers are the Wharfedale Denton 2s that I bought just before going up to uni in 1972, and so I want not just a wi-fi signal, but something with enough power to drive a pair of passive speakers. I actually don't think it's possible - I'll just have to run some thick wires. Cooking with Floyd, or Emerson, Lake and Palmer, with the garden door open should annoy the neighbours!

The Air India flight 171 crash on 12 June which killed 241 passengers and crew 32 seconds after take-off from Ahmedabad airport in India was related to the fuel cut-off switches according to the Air Current website. https://theaircurrent.com/aviation-safety/ai171-investigation-fuel-control-switches/ The WSJ and Reuters are reporting the same sources and findings from a preliminary report as well. According to these reports, both fuel cut-off switches were found in the CUT position, which should be an impossible scenario if the crew had been following SOP. https://www.youtube.com/watch?v=MD64uYK926o Even if one engine had failed on rotation as the plane took off, SOP dicta…

How can higher bypass-ratio turbofans be fitted to conventional planforms of low-wing design ? This question has gained great importance within the air-travel industry in recent years , primarily because of the financial impact greater fuel-efficiency can have upon an airline's profit margin . Prior to now , the standard answer was to install wider engines , this in spite of the significant modifications necessary to fit such to aircraft originally designed for much narrower ones . The drawbacks of this approach are numerous , and involve components such as landing-gear , fuselages , wing-structures , engine-mounts , and even avionics and cockpit layouts . The B.737-Max d…

Just seen an interesting bit of 3D printing on the TV programme about the current Chelsea Flower Show. They were using fine concrete as the print material, and the print machine was 2 - 3 times the size of a human. The result was a hollow cellular wall.

https://www.theguardian.com/environment/2025/jun/26/global-shipping-emissions-invention-clean-up-cargo-fleets-net-zero The idea here is to use quicklime (Calcium oxide, CaO) to absorb CO2 from the exhaust of ship engines, generating calcium carbonate (CaCO3, limestone, chalk etc). And they speak of using renewable energy to power the kilns that generate the quicklime. But, er, the kilns generate CaO by driving off CO2 from calcium carbonate. So all you've done with this proposed technology is move your CO2 from the ship to the shore; you still now need to dispose of it, somehow. I don't see in the article where this issue is addressed. Does anyone know more about this? I…

Good day. A lot of information available on the net; but seems the surfaces where it can be applied is missing details. What have you experienced or can comment/supply guidance ? Read the surfaces to apply can range from bare concrete block walls; bare brick; old deteriorated paint of several types as latex, colors that may bleed out, oil based, limewash... After nail holes are filled, preparing white Portland cement plus water and nothing else to the consistency of 'toothpaste' and applying with paint roller, brush, scraper?, to a smooth finish that will even and cover irregular lines. My specific case is 80 year old plaster walls with the corresponding scars a…

Hello all. chalk, gypsum, hydrated lime, magnesium carbonate, sodium carbonate, calcium sulfate, clay Seems there is a fine line differences in these minerals and their uses. Can anyone shine some simple light on their uses, properties ?

I am having trouble understanding how a parallel circuit actually works, on paper. Below is a cluster of solar cells on a panel with strategically placed diodes so that each cell can work independently to its maximum if part of the panel were shaded: First of all I need to know if that concept works (I just assume that it does because others sell such panels), over a serial design where a portion of the panel being shaded would simply reduce the entire panel's output, thus making it less efficient, but cheaper to produce. Presently there is a single diode inside the junction box (not illustrated with a circle, at the left of the illustration i.e. top of the panel), whic…

Maybe I found a infinite motor powered by hydrogen? This is a very first prototype that I idealized, before I explain how it works, I want to establish some points: I'm not a professional engineer, i'm just a enthusiast of aviation that was lost in rambling trying to find a sustentable engine. Probably it is subject to some flaws, and I need help from internauts to show problems to solve them, probably in some future it can be sufficient to power a entire Boeing 787. And lastly, it maybe also be completely flawed and be subject to redesign completely, and even being archived or abandoned. So, how it works? Well, it works in a cycle, that is depicted on the attached file b…

Any guidance to produce rubber parts with a tridimensional printer ? If gets too complex, perhaps some hard silicone instead ? Or room temperature vulcanizing RTV ? Would ultraviolet curing be ineludible ? What rubberish materials cure with UV ? Can 3D printers carve material out instead of pouring ? As to create a mold ? Is it just matter of putting a 'negative' image file to 'print' a mold ? Any capable hobby machine that you know of in the market ? As to start from a rubber block ? Yes, too many questions... tackle as many as you want.

Hello all, I am developing robotic workstation with holding electromagnet as gripper tool. Electromagnet has holding force 45 N, Rated input power 1.4 W, 24 VDC, diameter 18mm. It was supposed to attach game pieces (application of playing checkers with a small robot). Game pieces are small cylindrical 3d printed parts, weight about 3grams, they have 2 washers inside the piece on top of each other (there are 2 washers (2mm) and then 1mm layer of print material). The problem is that electromagnet is too weak for that piece. Im thinking about boosting pieces with neodyme or ferrite magnet instead of washers (140HV). What do you think about this? That holding electromagnet is…

I am wondering if we can gather enough data showing objects interact with each other is it possible to train AI to learn laws of physics. For example if we record behaviour of an siolated system involving few objects and use that data to build model such that it predicts motion for next few frames. Is it already in work somewhere? I am an amatuer so I would love to learn from you.

Spain and Portugal have suffered major electrical blackouts affecting capital cities such as Madrid and Lisbon, plus many other regional cities such as Barcelona, Valencia, and Porto. Parts of southern France have also been affected https://news.sky.com/story/spain-portugal-power-outage-latest-large-parts-of-countries-affected-with-traffic-lights-not-working-and-phone-lines-down-13357538 REN the prinicipal electrical grid operator in Spain has blamed rare atmospheric conditions that have affected significant parts of the European power grid system for causing “induced atmospheric variations” which have impacted the operational stability of power transmission lines acros…

Will these new bats be banned, as the controversy grows, or will everyone in MLB soon be swinging them? At some point, further testing by a panel of engineers may be needed, lest fans are driven batty. https://www.npr.org/2025/03/30/nx-s1-5344998/new-bats-yankees-record-breaking-home-runs According to former infielder Kevin Smith, the Yankees' new bats were designed by Aaron Leanhardt, a former physicist turned baseball coach. Leanhardt, an ex-physics professor who earned his doctorate at the Massachusetts Institute of Technology, has been working for the team for over six years. He used to be the Yankees assistant hitting coach, before becoming an analy…

London Heathrow airport has been completely shut down today by a major fire in a nearby electricity distribution substation which also took out power to 62,000 local residents. Authorities say that it may take a number of days to restore power to the airport, and air travellers are being advised to avoid Heathrow completely until further notice. https://www.bbc.co.uk/news/live/cly24zvvwxlt The fire at the North Hyde electricity substation in Hayes began last night at 23:33 GMT with an explosion in a large transformer which set some 25,000 litres of cooling oil on fire, destroying both the transformer and a nearby backup generator. This is a nightmare scenario fo…

Well the video highlighted the mission would highlight that women and minorities lead the mission. Which is ok. I am just poking fun of the fact that it is costing a 100 billion dollars. This mission is way behind. If we were on the moon in 1970’s why is it so hard to go back? Yes I know these women are good astronauts. Putting someone on the moon is great, but if you say first woman on the moon, $100,000,000,000. Eliminating the need for DEI, priceless.

Hi, I’m a research student working on a lightweight robotic arm. I’m looking for materials that balance strength, weight, and cost. Are carbon fibre composites worth the expense compared to aluminium or titanium? Any suggestions or experiences would be helpful. Thanks

People living near Lands End Cornwall UK have been advised to buy earplugs due to a lighthouse’s broken fog alarm https://www.bbc.co.uk/news/articles/cdelld75wgro The Longships Lighthouse has been sounding a loud beep every 13 seconds for the last week after a visibility sensor malfunctioned. Trinity House who manage all of England's lighthouses say they are aware of the fault, but are waiting for a spare part to arrive. The lighthouse which dates from the later 19th century has been unmanned ever since automation was installed in 1988. https://en.wikipedia.org/wiki/Longships_Lighthouse The previous pneumatic supertyfon foghorn was removed at the …

In big wave surfing the wave heights are estimated based on how tall the surfer riding the wave is. The surfer is the unit of measure. IS THERE A WAY to use radar, lasers, GPS, or whatever electronic devices, to exactly measure the height of a breaking wave, from the shore in real time? For example, this is how a wave's height is currently estimated: Mike Parsons at Cortes Bank on Jan 6, 2008. 13 times overhead. 13 x 6 = 78 feet. The actual estimate was 77 feet. Here is a recent wave at Mavericks, on Dec 23, 2024, that some are calling 100 feet tall. But how tall is it really?

While working on a lightweight robotic arm for pick-and-place tasks on a mobile platform, I’ve been considering how to balance weight, durability, and manufacturability when selecting materials. In practical applications, which trade-offs have you found most significant when choosing between options like aluminium, titanium, or carbon fibre? This question arose after reading an article discussing how industrial robots are revolutionizing engineering projects, which highlighted how material choices can directly affect efficiency and design (https://www.theengineeringprojects.com/2023/11/how-industrial-robots-are-revolutionizing-engineering-projects.html)."

How can advancements in smart materials, like shape memory alloys or electroactive polymers, revolutionize the design of lightweight robotic arms, especially for mobile platforms? Are there practical challenges in integrating these materials compared to traditional metals and composites?

I was thinking about the Fan on my Laptop. It goes *Brrrrrrrrrrrrrrrrrr* when I play a game on it. I was wondering how it could be quieter. I remembered Dyson's Bladeless Air Fan, but that's patented. I got stuck thinking about this for a couple of days. I saw SpaceX's Starships have Microscopic grooves all over itself. I also saw that they are 3D Printed. It finally came to me; What if....... the same area of the one Fan.......... was replaced with............... 3D Printed Microscopic Fans........ Occupying the same sapce instead.

I am trying to fit a solenoid into a greeting card to animate parts of it. I would like it to run on the sorts of power sources that could also be squeezed into a greeting card, so coin cell batteries, or very thin flexible solar panels. To that end, I have been trying to learn about how to optimize the design of a solenoid to get the most bang for my wattage, and mostly running into more and more complications. I am hoping someone can help me understand sort of practical rules of thumb for solenoid design. For example, in trying to keep my solenoid very small in diameter, I wondered if I could make up for it by making it longer. If I understand correctly, the equati…