Engineering

I never did much with gears. I have a rack with 20 teeth and I want a very small gear to fit on it. I would think that if I wanted the size of the gear to be, say, 1/2 the length of the rack in circumference, then the gear would have 1/2 the number of spurs but with the same length and height as the teeth on the rack, but I don' know for sure. I mean you can't just have different sizes and have the gear with the same number of teeth on each gear could you? At some point it seems like it wouldn't fit.

Nowadays we already heard and see the auto-pilot vehicle invention but does it really practical if all the vehicle in this world are all auto pilot. What is the advantages and disadvantages of auto-pilot vehicle invention if in the future all vehicles are going to use fully auto-pilot vehicle invention?

So the gist is that i'm a new scifi writer and i just want some peoples input on what are some technology, gadgets and weapons we'd find in the future?

Hey everyone Recently somebody told me that microwaves cause cancer because they use radiation to cook the food. He said that since radiation causes cancer then "logically"(improper use of logic) microwaves cause cancer, and that it was a government conspiracy blah blah blah. Either way in a week 3 MORE people have said it, different stories behind the thing but the same basic principle, radiation causes cancer so microwaves cause cancer. So I looked it up, and lots and lots of people are saying it. I looked up how it works and it says it uses radio waves at a set frequency to agitate water molecules. This causes them to vibrate and cause friction, which cooks your …

Hello everyone, i didn't have time to study the solving techniques in Simulink/Matlab, so i'm just asking Matlab users, which method is more reliable ? and giving accurate results which are close to those of experiment ? I use Runge Kutta often for its precision, but in a new simulation it wasn't reliable, and Bogacki Shampine was better. Thanks in advances for your answers. PS: i wasn't sure were to post this topic, but because Matlab is used by engineers mostly, i chose to post it here.

Hello everyone, the other day a friend of mine said that we should harness the power in lightning to power everything. And I quote he said "One lightning strike has enough energy in it to power my entire town forever!" Now this is high school, so obviously his thoughts on how much energy that is in a lightning bolt is greatly exaggerated, or he doesn't understand that energy gets used up in kilowatt-hours rather than simply kilowatts. Either way, I failed to mention this and said that he may be able to use a superconductor if you could get the lightning to hit it. He said ok and went on his merry way. But upon further thought when I was bored I began wondering if theres a…

Hello all. If a solar panel during cloudy daylight gets total shade on several cells, as from an object fallen/covering them ; If a solar panel in full darkness at night gets some cells illuminated by a flashlight ; Is there still some current passing/generation in both cases ? Or dark cells will block flow of current for the whole panel ?

Since we are thinking about colonizing other planets, it would be goood to establish test colonies in some more inhospitable places on the Earth. I am thinking about a test colony for between 300 and 1000 people, located either somewhere in Greenland, the edge of Antarctica or northern Canada is it possible to establish a settlement in these areas that is self sufficient in food and energy, using technology available in 5-10 years? The town would be built with a fairy high initial ivestment. Energy would be generated via solar, wind and possibly tidal generators and food would be grown in greenhouses. It would be built on a low lying area with a possibility of fi…

Every type of electric thrusters used in space that i have seen ejects matter to move, even the ionic thrusters use xenom to move, fully electric thrusters exist?,

Aparently fuel is one of the biggest problems with rockets and spaceships, because the most part of rockets are fuel tanks, could nuclear fuel be contained and used to accelerate spaceships using less space and more power?

Unmanned Expedition to the https://en.wikipedia.org/wiki/Wolf_1061c Let’s consider that mankind is able to build a version of: https://en.wikipedia.org/wiki/Fusion_rocket Namely: The NASA/MSFC Human Outer Planets Exploration (HOPE) group has investigated a manned MTF propulsion spacecraft capable of delivering a 163933-kilogram payload to Jupiter's moon Callisto using 106-165 metric tons of propellant (hydrogen plus either D-T or D-He3 fusion fuel) in 249–330 days.[5] This design would thus be considerably smaller and more fuel efficient due to its higher exhaust velocity (700 km/s). In 2006, the United States was estimated to have a production capacity of 11 mi…

An electret microphone has air between the capacitive foils. To operate it in a pressurized 4 atmosphere air chamber, would have to be vented to prevent imploding. Could perforating a tiny, tiny 0.1mm hole in the electret foil cause concernible degradation on its performance ? Or, side venting the housing voids ? Or, ... ? Figure 10 ----> http://www.openmusiclabs.com/learning/sensors/electret-microphones/

Wow, I didnt know of this forum love it Looking for a material with very high emissivity to work as a 1m2 black body, absorbing concentrated solar light transferring the heat to the material under, standing a temperature preferably around 1000-1200c for longer periods of time. It will be in vacuum too. Also I'm looking for material with very low emissivity material that can stand temperatures of at least 1200c preferably more, over long periods of time It will reflect concentrated solar light Both of them will be in 1pa vacuum and preferably somewhat abundant.

What is the typical operation limits of AC power meters ? Do they register -say 10 mA ? Water meters are unresponsive to a drip, drip, drip... Vanes do not turn at very low flow. Is there a typical minimum ? What does wear imply in them, -say ten years.

Hi Looking to get some understanding of machine sizing, but I cannot seem to find a source for the derivation of these output equations for the IM/SynM. Could anyone help with this derivation or point me in the direction of a source? CK

Is there any economical or scientific reason for manned missions to other celestial bodies? While manned mission will most likely be able to collect scientific data faster than unmanned drones these will be very limited in terms of duration of their stay and so devices like Mars rovers might be able to outperform a manned mission both in terms of amount of scientific data collected and at a fraction of the cost. Another option is a long-term manned research base, which, while being extremely expensive will not be as limited in terms of duration of stay and be able to collect scientific data faster than unmanned devices. Which one of these three is better in terms …

In this design, the engine is a combination of diesel and jet engine technology. A 36-cylinder diesel engine is the core part of the concept, operating like a pair of linked up 18-cylinder motors. The front engine is a bit wider than the rear one, but has a wider, hollow crankshaft rotating one way while the rear engine crankshaft rotates the other way and extends through the first one. Questions regarding the piston portion of the engine: - In this idea, the engine uses lightweight but strong high temperature alloys. I'm imagining it to be a mix of beryllium, titanium, and magnesium, maybe the cylinders could be made from high-temperature strength steel if need…

I my trying to build and oven need materials to use for interior and exterior

Hi! I'm new to this, but I was just wondering why the heck nobody has started manufacturing Nixie Tubes?? I think it would be a great business selling them for super cheap!!

Hello everyone, I am an Engineering student currently working on a project. The project is to design and fabricate CSP (concentrated solar power) based vapor absorption refrigeration system. I hope everyone here knows about vapor absorption system and its components. The problem that led me to post here is that, I am using concentrated solar power from a parabolic trough as a heat source for my generator. The generator is actually a pipe which contains the refrigerent and absorbent solution(LiBr-Water),the generator is directly exposed to the concentrated solar light. Now I am all set with other components of the system, the only problem is: "I have T1 as temp…

Let's say that I power a solar panel indoor (underground or under roof) with artificial light, and I place a concave mirror on top of both the solar panel and the light, how efficient would this be?

Is it possible to create 2D screenless displays? What technology would you propose?

With oil dropping to $30/barrel..and possibly dipping lower, is there pretty much no hope for alternative fuels? With gas being near $2.00 a gallon, I don't see any infrastructure being laid out for AF use/ research. I'm a big advocate for AF and this makes me sad. Thoughts? ~EE

In need to seal a sturdy PVC plastic bag with a flexible, permanent, agressive glue. Thermosealing / thermowelding would be the correct way, but not on hand to do it that way. The bag shows "Recycle 3" which should be PVC, made of about 0.3mm thick 'films' Unsure if something that somewhat dissolves the material to form the bond would be better. Any product recommendation ? ----> http://www.diomedia.com/imagePreview/01AFTGU4?imageId=9927668&imageCode=01AFTGU4&contributor=Phototake+RM&siteName=www.diomedia.com&title=&location=&ds=760&newStyle=1&tc=FFFFFF&tbc=333333&qv=95&icc=1&cl=1 No, it is not refilled …

Hello everyone A friend of mine is working on smart houses where devices are connected to each other wirelessly and connected to a computer then to internet ... now, many engineering projects are extending this study to make smart cities and then smart planet. The question is, with each technology comes some risks, .. do we really need smart cities? and how risky would it be to make all devices in a big city connected to the net ?!