Engineering

Hi. Trying to find if there is in the market a mechanism that holds a string under pulling force by pinching and releases it by a solenoid or lever. Or an off the shelf device/gadget that can be re-purposed. String wound ------------------------pinching mechanism------------------------>20 Newton pulling force in a bobbin ^release solenoid^ Have you seen such in everyday items ? Sort of clothesline extender, window blind or something alike... Just trying to reuse instead of re-invent/design. If possible plastic, or non-corroding. Not self-rewinding as a measuring tape.

Hello everybody I'm from Iran and I have an urgent question, I want to find username &password of scientific University such as New York University and McGill and the other famous universities. Pleeeeease help me about finding MD accounts, If you don't have any information about my question, please introduced some forums or sites that they are selling or sharing these accounts... Thank you

It's a rather dumb question, but here it is: My thought of the major factor in efficiency between the two turbines is the amount of variation of temperature within the engine itself. *Does this hold true?* Here's my theory: The more consistent the temperature, the higher the efficiency. Gas turbine: Combustion of gases would have a slightly more temperature fluctuation due to occurrence of incomplete combustion of gases. Steam turbine: External source of heat constantly maintains gases' kinetic energy, keeping the heat consistent. Also water has a higher specific heat. Therefore, the steam turbine would theoretically be mo…

Global Positioning systems are extremely accurate typically <10m, assuming there is good satellite coverage. Satellites have both high and low orbit, Inmarsat coverage is particularly poor. I would like to start a discussion ref the reliability and accuracy of the various GPS networks. I am particularly interested in how the accuracy, or time, of the clocks may be affected if they are in different orbits around the planet, or at different altitudes or orbiting in different directions. For example if in orbit around the equator, at higher latitudes or perhaps orbiting over the poles. The reason the question occurs to me is that I use GPS in navigation off sh…

Might seem like a simple question but when I thought about it, I think how the wheels of the train stay on track needs to be elaborated. Sure, if the train travels only in one track, it has a steep extrusion at the middle of the wheel which allow it to stay in track, but... If it crosses another railway, how can we make sure it stays in track? Go here if you don't know what I mean: https://farm3.staticflickr.com/2513/3874671000_349f1f4b18_z.jpg?zz=1 http://static.panoramio.com/photos/large/58668679.jpg

Hello! What material would be best for condensating steam back to water outside? *To clarify, I am making something which involves turning jets of steam back into water outdoors in the blazing sun (Texas, baby!) and I need a cost-efficient material which I can shoot the steam against and have it condensate quickly back into water.

Please help me find the advantages and disadvantages of flying carinvention to our daily life

Hello, can you suggest me some good project ideas for a civil engineering student?

I have recently discovered that air is not just ionized by nature, but also by electromagnetic radiation. I have two questions: 1) how much electromagnetic power is needed in order to ionize the air (in terms of kw) 2) Does ionized air cause any adverse health effects when the ionization is caused by electromagnetic forces, rather than nature? Thank you

It's almost spooky what a robot will do with just a few simple rules, as with a PID controller. In my project below, at 1:20, all I do is issue a forward-command, and the system moves backward momentarily to tilt the robot forward, and then it moves.

Hi, Any advice on what the best type of heating solution would be for the following scenario? I have seen some large infra red patio heaters and have also looked at some gas panels. I am not sure if the IR will kick out enough heat for what we require. We need a heating panel (can be gas, electric, whatever) that is large and will kick out enough heat so that something left near it will start to singe. Ideally the item (a wood panel) will reach a surface temp of around 400C and stay about there. I remember the old electric bar heaters that were hot enough to set stuff alight if you left things too close.. (my nan's dog regularly ignited its fur by lying too cl…

I am a bit baffled why the Stirling Engine is not more commonly used when we, as a global community, need to turn out engines which are quiet and clean with a lack of heavy pollutants? What are the restrictions stopping the use of this beautiful engine? Link http://upload.wikimedia.org/wikipedia/commons/c/cc/Alpha_Stirling.gif

I didn't calculate anything till now, I don't know if radiation pressure is good enough to propel a spacecraft(My question). Obviously I'm talking about radiation pressure coming from radioactive dregs of nuclear fission! How it works? It's sufficient to release radiation in the space to have a propulsion in the opposite direction: it's conservation of quantity of motion because radiation pressure is a palpable quantity of motion!

Hi all. New to the forums but wanted to share a project I've been working on for a while. Since highschool I've been messing around fusors and other plasma based devices. I recently made a video going over some of the basics of working with these kinds of systems using mostly salvaged parts. Hope you enjoy

gif of girl with amputated hands using bionic hand: https://gfycat.com/VacantRequiredAmethystinepython How does the bionic hand know/recognize nerve signals being sent to the area that would be her hand? Also, how is it calibrated that it provides the right amount of tension with the nerve signal? ~EE

Hello to everyone , i spend 1 year in observing the whole idea an i solved it . my Question is do you think it is worth it to send the blueprints to some university ?

Photographic filter holders are usually metal. Looking for a source of plastic ones, to avoid corrosion. Need is to hold diaphragms instead of optical filters. Can be from any application other than cameras. Sample pictures ----> https://www.aliexpress.com/item/NEW-Camera-Filter-40-5-43-46-49-52-55-58-62-67-72-77-82mm/32655570830.html?ws_ab_test=searchweb0_0,searchweb201602_4_10152_10065_10151_10068_10130_10084_10083_10080_10082_10081_10110_10178_10136_10137_10111_10060_10138_10112_10113_10062_10114_10156_10056_10055_10054_10059_10099_10078_10079_10103_10073_10102_10096_10070_10148_10123_10147_10052_10053_10124_10142_10107_10050_10143_10051,searchweb201603_1,af…

I'm just asking when I woke up in the morning I just remembered a YouTube video about time traveling,a thing or a machine that is faster the the light can cause up time-warping(or time-travel). So a brilliant Idea just come out on my mind to make a sketch plan for a machine that can run fast in a miles but it not possible as well. A bullet train in Japan can run as fast as a sportscar but I need an idea for this (time-travel). In YouTube I just randomly found an interesting video that America has has a secret plan for making a time machine BUT I DON'T BELIEVE AS SOOO. So my point is what machine that can run fast

An oven using electric heating elements creates zones that widely differ in temperature, depending on proximity to the red hot heating element. Some modern units with a fan for circulation of hot air inside, should be considerably better. Microwave ovens deflect radiation into all directions with rotary motion. Can some type of moving 'mirrors' be implemented to incandescent heating elements to spread the radiated heat evenly without air currents ?

I am wondering about the feasibility of re-tooling gas stations (petrol stations) as follows:- >>> Instead of delivering hydrocarbon fuel (petrol) to a vehicle with an ICE, they would recycle the in-vehicle battery electrolyte stored in the traditional fuel tanks of an EV Factors to consider would include:- - Reconfigure EV in-vehicle systems to monitor and recycle the battery electrolyte with fresh electrolyte from vehicle gas tank - EV would attend a gas station periodically, which would pump out the spent electrolyte from the vehicle holding tank and pump in new 'charged' electrolyte - Gas stations would have device/appliance to re-charge and recy…

This latest episode in the Graphene story is looking very promising. I seem to remember Lockheed Martin claiming something similar a few years ago, but these people seem to have cracked the desalination bit of the puzzle, and it could make a huge difference to the energy and running costs of desalinating water : http://www.manchester.ac.uk/discover/news/graphene-sieve-turns-seawater-into-drinking-water/

small generator lighting 7 W led bulb 230 V E 27 homemade and another small generator is lighting 230 V Mr 16 led 3 W the movie: it will be possible in the close future to create one more powerfull?

it has missing parts so if you figure it out you can build it

I need a reccomendation on a heat resistant material for temp up to 300 degrees. Will be used in solar water heater. Should be readily available and inexpesive.

Sorry if this has already been posted, but this has been bugging me for a while and a search didn't turn up anything. We keep talking about alternative energy sources everywhere when there is a constant energy around us all the time. What I want to know is, could gravity be used as a feasible source of energy?