Backward Typing!

I just published a topic on cleaning juice stains from carpet. (home section) When I first started writing the topic, my 1st sentence came out ".der gnihtemoS" At first, I said 'what the??!!"  but then I realized that it was PRECISELY backwards of what I had written. "Something red." After deleting the glitch sentence, it went normally. Curious.

Posted by Toga_Dan 2 years ago


Ok so i have a little problem here... i want to make a little electric motor go forward and backward by pressing a single button for each move (so 2 button in total) i got a little image ( poor quality i know but youl get the point) of what i did but its doesnt work :/ thx

Posted by koax 10 years ago

Loaded backwards

This one day, I was trying to open a page, and I noticed something funny. The thing at the bottom of the page that shows you how much of the page has loaded was going backwards! Seriously, it was on 99, and then it went to 97, 89, 78, 65, 55, 43, 20, 4... My Fasterfox timer (which counts how long it takes for your page to load) even started going backwards! Ah well. I guess that's just what I get for using an old version of Firefox. (2.00.01, I know it's old.)

Posted by YummyPancakes 10 years ago

messing with a clock

For Halloween I want to create a little knock off of the clock from Disney's Haunted Mansion. I have found a great image of the clock face online. How feasible would it be for me to hack a simple electric clock and have it 1) run backwards and 2) run very fast Thanks!!!!

Posted by Purple Chez 1 year ago

Star rating going backwards help

Please fix I had about 5 friends who gave me five stars And each time they voted my rating would go down. I now have 1.88,please fix and if you can put My instructable at the correct number of star and rating. Thanks very much!!

Posted by vader119 9 years ago

The World Is Going to Explode!

I came here and all of the sudden, the whole design is backwards (which looks like shit by the way). How long has the world been spinning into disaster like this?

Posted by Crash2108 11 years ago

Srac Sdrawkcab.

Here's a bit of fun; lift the top off a car, flip it front-for-back, and refit it, all in Photoshop. From FinalGear via NOTCOT. Go on, let's see your photoshoppery and gimpery.

Posted by Kiteman 7 years ago

Bug using NEXT and PREV buttons

Hi,   Using the next and previous buttons when searching for related instructables adds a backwards slash (\) to the URL resulting in a "Request Too Long" error after the 13th page.

Posted by affix 7 years ago

Phase Cancellation to Prevent Feedback

The Grateful Dead's wall of sound prevented feed back by having two mics for each vocalist with one of the mics 180° out of phase of the other. Then mixing both mics on the same channel. So the only information that wasn't canceled was the voice.  This gave me an idea. I took a handset and added a mic facing backward from the existing mic. Then wired the second mic out of phase. Apparently there's more to it electrically then just wiring the other mic backwards because the handset went dead. Is this possible with just parts salvaged from old phone equipment?

Posted by AJRimmer 5 years ago

Knex scar L not working?

My scar L is not working when i pull the pin back the bullet goes backwards and forwards sometimes and when it does fire it does not go very far any ideas on how i can fix this?

Posted by pongopeter826 4 years ago

Voltage help

Hello I am new to electronics I am having trouble designing a circuit that lowers VDC as ground resistance increases and raises as ground decreases every circuit I've built works backwards. I am working with 5vdc any help would be much appreciated thanks

Posted by Ed69 1 year ago

Front page is broken

The front page is broken. First, words typed into the large search box come up backwards (can't upload screenshot due to "server maintenance"). Second, hitting the space bar whilst typing in the large search box takes you to the end of the front page. So, trying to type in "cable reel" shows "elbac" in the search box, then you jump to the bottom of the page. Third, the drop-down menus (Explore, Create etc) do not work on the front page. (But, the small search box at the top of the front page is working) This is not just on my home computer - Kitewife just phoned me to tell me that they were having this problem at her place of work (she was trying to show some colleagues some knitting techniques, I think.)

Posted by Kiteman 4 years ago

CD to LP Help!

I have a CD of mine that I really would like converted back to vinyl is this possible at all?The only thing that I could find is LP to CD conversion such as this site hereAnyone know anything about this?And the CD is Buckethead : Enter The Chicken : P

Posted by jackillac92 9 years ago

PWM to Digital Signal

I am trying to make an R/C sumo bot for a competition. What would be the easiest way to run regular DC gearhead motors from a servo controller? I'm thinking of somehow converting the pwm signal into a digital signal that would run the motors forward or backward.

Posted by Stingray 7 years ago

I can't see my instructable

Last night I published this instructable, but I can not see it in ALL RECENT option. However, it has a comment. I don't understand... What worries me is that when you solve the problem, my instructable will appear "backward" or as posted several hours ago, and many people will not see it, for that reason.

Posted by rimar2000 6 years ago


Hi, I'm making plans for a remote control car from scratch, and have a few questions. Are hobby motors able to go backwards, how do you control that? Any ideas on making a wireless usb cord for a webcam? Do you know of any small things (like motors) that could move a switch remotely for the steering mechanism? Any other ideas?

Posted by Weissensteinburg 11 years ago

USB Flipper

Here's an idea for those USB connectors in hard to reach places. main site: press:;_id=222902730 video: contact info: Not my idea, saw it recently in eetimes.

Posted by backtalker 8 years ago

Forward/Reverse engine using 2 micro pins - How?

I've been wanting to get into more advance projects after i've down lights, tunes, and other things. So first to mind, knex and motors. have tones of it. The only problem, How can i get a forward/backward on the engine, with just 2 micro pins? This is a normle + - motor.

Posted by Killa-X 10 years ago

Wanted: setting to view all comments, oldest first

It's hard to read recent comments first. It's like reading a book backwards. Could we get a profile setting that would always show comments, oldest first? I can click on the link by the comments to resort them, but I have to click that link on every instructable, and even after I post my comment it goes back to most recent comment first.

Posted by chuckr44 11 years ago

batlefield 2142 E.U. tank made with knex.

Her is a tank that can go forward ,backwards and in circles. post a comment if you like it or want me to post. works best on hard wood floor or bed sheets. the pictures are so bad because I was in a hurry so... sorry. :( 1.front view 2.the behind view 3.the under side this tank was tough to build ,but its sweet.

Posted by the_burrito_master 10 years ago

Adding remotecontrols to electric devices

I am looking to add a remote control to a circuit board which controls two separate motors (forward/backward and left/right) The control should be pressure sensitive. right now the control is a mounted 4 directional switch (like on a motorized wheel chair). How can I add a remote to it? I have an old R/C car board, and the remote that goes with it.

Posted by DaMadProfessor 10 years ago

You guys remember this traynor?

I think some of you will remember how I was attempting to find out the specs of this traynor amplifier. Well after someone pointed out to me it was most likely for the speakers on stage that point backwards towards the band so they can hear what they're sounding like. It went away into a closet and didn't come back out till yesturday.

Posted by Punkguyta 9 years ago

Show moves

Hi everyone, i was wondering if in parkour and freerunning "shows"(ie. Showing off to a small crowd) if you have any trademark tricks? Just name/describe/post a video of you doing your trick, and maybe suggest improvements as well. My showmove is a front-somersault with a 180 twist, then going backwards in a handstand for 5 seconds. It's less impressive than it sounds, but it gets a good roar from the crowd ;)

Posted by The Jamalam 10 years ago


I want an rc helicopter that is reasonably priced, easy to manever (the type that you can go forward and backward, up and down, not too touchy, etc.) tough (i am a beginner, so i crash alot) has a long battery life (unless it's a gas) weather proof (will not get blown so easily by the wind) and if it's outdoors a reasonable size (i want to make a bombay door or something so i can drop stuff

Posted by TheInventor1997 7 years ago

My RC car circuit board

Hi, i need some help. A few weeks ago i took apart a RC (remote controlled) car circuit board but some of the cables couldn't hold and just broke off so i'd be so thankful if one of you smart people out there could tell me (or draw on the picture) where everything is supposed to go (including the antenna :-) and the forwart and backward motor. thanks Kacper

Posted by kacper00100 10 years ago

pwm arduino

I have a couple questions about driving motors from the arduino (I have a boarduino) - First off, these motors are from various walkmans and I think each one is rated for 1.7 volts. - If I need a transistor, can i use a 2n3904 (since these arn't giant motors) - How do I protect against the emf? The motors need to work going either way (clockwise or counter clockwise) - How would you program it so that the motor can go either forward or backwards?

Posted by guyfrom7up 10 years ago

Why are "ground" and "(-)" often referred to as the same thing.

Ok, so, I am very confused with wire colors, ground and (+) and (-). I NEEd someone to answer me. What I have read is that electricity flows from (-) to (+). However red wire is always connected to (+) and referred to as the "hot or "live" wire, and (-) is the ground. This seems backwards to me. Ground wires go to ground because it is highly positively charged, It just seems like there is contradictions. I really need this cleared up. Thanks in advance!

Posted by Ampix0 5 years ago

Remote controll help

Hello. Could someone please help me? I would like to build a remote controll ship, but I do not know how to solve the problem of remote controll. My plan is to controll 2 electric motors, each 4.8 volts dc, separately forward and backward from 6volt batteries via radio controll. Could someone please send me drawings for the sender and the receiver circuits so that I could remote controll the 2 electric motors? I would be really thankfull for any help.

Posted by Vaszilij 6 years ago

Is the reverse voltage on all LEDs always 5v or more?

I have a bunch of LEDs (mainly 0603 and 5050 smd, 3mm, and 5mm - all colors).  Most of them don't list a reverse voltage.  Those that do say 5volts.  My question is, do any LEDs have less than 5v reverse voltage?  Is it possible to accidentally kill them by connecting backwards to a 5v power supply?  Should I put resistors on both the positive and negative to protect them (would that even work)?  Thanks.

Posted by aliasjanedoe 4 years ago

What are the best examples of fails, stupidity, and general ignorance that you have witnessed?

I was browsing ibles yesterday, and I came across this stunning piece of stupidity: Person 1: "d - b" (some interesting ASCII art) Person 2: "How do u get the backwards b" Me: "It's called D" It got me thinking afterwards that I should make this forum. So, what are the best examples of fails, stupidity, and general ignorance that you have witnessed?

Posted by The Jamalam 8 years ago

Arduino multiple if statements

Hi, Thank you in advance for any feedback for my question. I made a XY plotter machine that I want to control with a joystick. The joystick has 4 momentary pushbuttons. One for up, down, left, right. I want the up and down to control one motor (or x axis), forward and backwards, and the left and right to control the second motor (y axis), forwards and backwards. I am using an Arduino UNO with Motor shield. I have all of the wiring part sorted out, but I am having trouble with my code. The problem is when I push forwards, the motor keeps going forward even when I stop pushing the button. I would like it to stop when I stop pushing the button. I am not too familiar with programming. Here is the code I am using: //Channel A or X Axis int upPinX = 2; int downPinX = 4; int forwardX = 0; int reverseX = 0; //Channel B or Y Axis int upPinY = 5; int downPinY = 6; int forwardY = 0; int reverseY = 0; void setup() {     //Setup Channel A or X Axis pinMode(12, OUTPUT); //Initiates Motor Channel A pin pinMode(9, OUTPUT); //Initiates Brake Channel A pin pinMode(upPinX, INPUT); //Motor A forward pushbutton pinMode(downPinX, INPUT); //Motor A backward pushbutton //Setup Channel B or Y Axis pinMode(13, OUTPUT); //Initiates Motor Channel A pin pinMode(8, OUTPUT); //Initiates Brake Channel A pin pinMode(upPinY, INPUT); //Motor A forward pushbutton pinMode(downPinY, INPUT); //Motor A backward pushbutton } void loop(){ forwardX = digitalRead(upPinX); reverseX = digitalRead(downPinX); forwardY = digitalRead(upPinY); reverseY = digitalRead(downPinY); if (forwardX == LOW) { digitalWrite(12, HIGH); //Establishes forward direction of Channel A digitalWrite(9, LOW); //Disengage the Brake for Channel A analogWrite(3, 1023); //Spins the motor on Channel A at full speed } if (reverseX == LOW) {   digitalWrite(12, LOW); //Establishes forward direction of Channel A digitalWrite(9, LOW); //Disengage the Brake for Channel A analogWrite(3, 1023); //Spins the motor on Channel A at full speed } if (forwardY == LOW) { digitalWrite(13, HIGH); //Establishes forward direction of Channel A digitalWrite(8, LOW); //Disengage the Brake for Channel A analogWrite(11, 1023); //Spins the motor on Channel A at full speed } if (reverseY == LOW) {   digitalWrite(13, LOW); //Establishes forward direction of Channel A digitalWrite(8, LOW); //Disengage the Brake for Channel A analogWrite(11, 1023); //Spins the motor on Channel A at full speed } else {   digitalWrite(9, HIGH); //Eengage the Brake for Channel A digitalWrite(8, HIGH); //Engage the break for Channel B } } - Also perhaps someone could let me know how I can insert code in one of those code boxes? Thanks,

Posted by toedip 5 years ago



Posted by cazmundi 11 years ago

Magic Freewheel & Bike Frame

The machine shop I work for had this "great" idea about 10 years ago. Wouldn't it be nice if you could pedal backwards on your bicycle and still go forward? It's like 2 things in one! Not as glamorous as it sounds. So I'm getting rid of some old parts to various "Super Gear" projects including the Magic Freewheel, an Aluminum bike frame, and if you really wanted them I an go dig out some of the old gears in storage too. Make an offer if you want something. We can ship UPS.

Posted by Rainbowlaces 8 years ago

What to do with an electric toothbrush?

The head of my electric toothbrush broke and replacement heads cost almost as much as I bought the toothbrush for, so I'm not going to buy a new one. I now have a headless electric toothbrush and wondered what make with it since it seems too nice to just throw away. Unlike most electric toothbrushes, this one doesn't rotate back and forth but instead reciprocates forwards and backwards about 2-3mm. Anyone think of something useful I could make of it? I tried to use it as a metal etcher, but it doesn't move fast enough for that unfortunately.

Posted by chiok 9 years ago

salvaging color displayscreens for other projects i need direction.

I have a picture here for you, I want to know how I would go about removing the lcd from this picture for other project displays. but I have never conceived of such a thing I need guidance and some tips and tricks. I am savey to several forms of backward engineering, as I said nothing like this though. I have no clue how to start. I would like to salvage it for easy use across multiple platforms weather be arduino, raspberry or custom boards. ( don't even know that's possible)

Posted by CD_tatro 3 years ago

Playstation 3 Info

So yes, my dad has said he will choose the PS3 as the free gift. So as you see im Estatic! I thought I might aswell get some info about the console, from gamers like yourself on instrutables. Just answer the questions: What is the best game to get on a PS3? Any regrets on buying it? ( e.g would of chose a different console, not worth it) Is it backwards compatible with other PS2 games ( if not is there a way to make it?) ? ( Im getting the 40gig - the only model available ) Which console do you think is going to win the next gen war? ( xbox has put up a good battle but the PS3 is picking up speed fast!) List of ps3 Must haves!!!? please. - Baron

Posted by Baron A 10 years ago

Worst prank EVER

So I broke a wheel off my lawnmower, no big deal, just weld it back on. How was I supposed to know that a wooden stump would break it? Anyways, since i have a shitty flux core mig welder from Harbor Freight, I decided I'd ask a friend to use their gas mig to fix it. I bring the lawn mower over, bring the welder outside, clamp the wheel bracket back on, and start the weld. All of a sudden, there's a huge ball of fire all over my mask. I immediately stop welding, and jump backwards.. yelling out, while he sits there on the ground laughing. He switched the argon with acetylene, at 10psi. Not cool. It was hilarious, but not cool.

Posted by cvxdes 10 years ago

I use TigerDirect for computer parts

. I've had good luck ordering computer parts from Wide selection and reasonable prices. I've been using them for 5-6 years now.. Sales support can be spotty; sometimes you get a salesperson that will lean over backwards to make sure you get what you need and other times they seem to be apathetic. Luckily, the former prevails.. I've only had to make one return and it went without a hitch.. The web site has an excellent search. When you search for, say, "monitor" the results page will have links to different size ranges and price ranges, allowing one to easily drill down to the right product.. . Disclaimer: My only connection to TigerDirect is as a satisfied customer.

Posted by NachoMahma 10 years ago

How can we build a cheap detector that senses a cellular (electromagnetic?) for use as a switch for a computer?

Hi all, we want to use a cellular phone as a "switch" to control a multimedia show. We thought of a cheap sensor that must be able to detect electromagnetic waves through a store window. We thought of phones because everyone has one in they pocket, phone is simply the source of the field. Idea is that customers can move their mobile phones in front of our store window to control a multimedia show in a simple way (forward, backward, pause), so in the end three or four different switches glued to the window would perform as a "control pad" for the computer. Maybe there is a way to base this project on products readily available which can be remodeled. Thanks for sour suppport and ideas! Nomax

Posted by nomax 7 years ago

Making it more powerful?

Hi,  I have brought a sphero 2.0 which for those who don't know it a robotic ball about the size of a baseball. I decided to try and make a car for it out of knex although I will only be able to make it go backwards and forwards. I built a frame thing with a small wheel in the middle of it and sphero sits on top. The axle that the wheel is on has a gear which then connects to the drive wheel axles on the back using another gear. This works fine when in the air but when on the ground it's too heavy for sphero to power it. I've tried putting bigger gears on the front and vice versa, i've also tried using a pulley but it just isn't budging at all.  Say if I was using the standard knex motors how would I go about making it produce more power? 

Posted by mikesaa309 4 years ago

need help controling dc motors

Im having a prob. maybe someone here can help. im going to be making a robotic arm for my wheelchair to lift and hold my tablet pc. im going to be using 4 mg996r servo motors moded to be geard dc motors. i own a (owi robotic arm edge robot) im hoping to use the pc board out of it to control the 4 motors forward and backwards,but i cant seam to figur out how to hook up a 6v acdc adapter to it to do so. here are pic of the edge robot schematics and a link to the manual (pdf) if anyone can help or know a easer way to control 4 motors both ways and not with arduino as i dont know enuff about them yet. edge robot manual pdf

Posted by skullkeeper80 7 years ago

want help with a possible future steampunk instructible

okay, so i want to make a steampunk contraption.  at first it was going to be a spring loaded gun like the derringer thing in sherlock holmes but with a huge gun (i actually have feasible plans in my head for that one.)  but it drifted off to make an even bigger gun.   i thought, and came up with an awesome idea. a retractable Gatling gun arm.  the gun will move forward, and backward, and will spin around. i made a 3d example to show what i mean, if i can figure out how to post it. [URL=;=MyMovie.mp4][IMG][/IMG][/URL] and if that's the wrong code: what do you think?  any suggestions, questions, ect?

Posted by badideasrus 7 years ago

Delta robot programming help

I recently created a delta robot with 3 rc servos and controlled with the arduino duemilanove. i was easilly able to create pre-programmed movements and get it to do simple repetitive tasks. but i would like to controll it with a joystic type controller(shown i pitcures) it has a 2 axis joystick and a single linear pot.i would like to use the joystick to control the x and y axis(foreward-backward,left-right) and use the linear pot to control up and down. the problem is is that the robot has all three axis on the same plane. so i need help trying to convert thes 3 seperate axis to controlling 3 planar axis. any help would be apreciated. thanks

Posted by budsiskos 9 years ago

Building a Transparent Dispay Monitor

I'm currently in the process of building a peppers ghost inspired computer monitor. I will be going through this DIY step by step and updating each time I progress. During this build I will be taking peoples suggestions from each previous step and applying it to the build. So this will be built by my and inspired by the community. First issue: I am using Lexan as the display and as you can see in the picture, I have already stumbled upon my first issue. Everything is backwards! So, first round of suggestions will be how to fix this. Note: Windows OS has built in capabilities to do screen ROTATIONS but not FLIP/MIRROR. I cannot stress enough how many people assume rotating, flipping, and mirroring are the same thing. In Microsoft's built in display panel they list: Landscape, Portrait, Landscape(Flipped), Portrait(Flipped). However the two flipped settings are merely rotations.

Posted by mae-kitty 3 years ago

Enforcing polarity with an AC adapter?

Several months ago, I posted an I'ble for adding an AC adapter to something. The adapter I chose, from Radio Shack, is actually a two-piece "kit" -- the wall wart cord ends in a generic two-pin female jack, and they sell a bunch of different end plugs. The jack is symmetric, so that the end plug can be put on with either ground or hot on the outside.I've just realized that this could be a problem. If the electronic device expects red to be positive and black negative, then putting the jack on backwards would be equivalent to installing all the batteries the wrong-way about. Not a great feature.To "protect" the device, I'm considering adding a diode bridge to ensure that the internal "red wire" always carries the positive, and the "black wire" is always ground. Do more experienced folks consider this a good idea? Is it necessary? Would it be better, perhaps, to just epoxy the end plug so it can't be reversed?

Posted by kelseymh 9 years ago

Where did I Go Wrong With My WASP?

Hey guys, I decided to build the WASP yesterday, but without instructions, as KI is down/not working (why is that? It has not been working for the past 1 - 2 months...?). I used pictures from ~KGB~'s WASP and Raz1r Knex Bull3t's WASP (click on their names to see their WASPs. ~KGB~'s is down in the comment section of the link I gave you.) I ran into two problems that I think you guys could help me with. Problem #1 The mechanism: Where did I go wrong? Every time I pull the trigger it pushes the hammer backwards, but it never lets the hammer fly forwards to hit the TR8 mini-primers. What is wrong? Problem #2 The turret: How can I get the turret to auto-ratchet? What should I do? Help...! -TRBoW

Posted by The Red Book of Westmarch 4 years ago

programming help

First of all, I am new to this. But for my CEIS course project I decided to program an rc vehicle because I thought it would be COOL! Now I am knee deep into the project and I am needing guidance.  So I am going to attempt to stack raspberry pi hats. One adafruit pwm for servos and the other adafruit pwm for dc and stepper motors. The first thing I done wrong was solder the gpio headers on backwards. Since I'm not too professional with a soldering iron I ended up making the drives of no use and ordered more. Before I done that, I got my pi camera working! Still need to program the pan/tilt servos. I have battery power, wiring, almost everything as far as hardware. Just not sure if I am headed in the right direction. I tried different things with python and the i2c but now when I start up the Kernel Module fails.  Any help will be great!

Posted by SMILEY4242 12 months ago

Arduino Car

Hi, So in computer engineering I've got to make a arduino based car, I've added a whole bunch of features such as IR tracking, obstacle avoidance(proximity sensor), optical tracking(follow a black line), and remote control through an android based phone. Since I'm a total newbie to technology I'm having trouble. I would appreciate it if You guys can point me towards resources and arduino libraries(for coding) that will work for me. Right now for coding I've only got basic pseudo-code setup since I do not know what libraries to use. I have searched up many sketches online and looked at them but didn't really understand any of the code. Here's the basic pseudo-code I got setup on the things that I've got to work on: DC Motor (4 of em for the wheels) (I also plan to add a stepper motor for turning right and left so if you could direct me on that as well) //Import necessary library //Setup the motors and pins //If signal for forward received //Code for moving forward //Set speed //Else If signal for backward received //Code for moving backward //Set speed //Else If signal for right received (keep turning right till stop signal received) //Code for moving right //Set speed //Else If signal for left received (keep turning left till stop signal received) //Code for moving left //Set speed //Else If signal for stop is received (Should we slow down to a stop or just stop?) //Code for stop //Set speed IR (I've got transmitting and recording diodes) //Import Library //Declare Pin for the IR Sensor //While loop: Move Right //If IR signal is received //move forward //Else //Jump back to top of loop Proximity Sensor (obstacle avoidance mode) (I might either use the one from Lego kit or buy a separate one ) //Import Library //Declare Pin for proximity sensor //While Loop: Send out sonar(echolocation or whatever) every second //Is there any obstacle?   //Yes, turn right so many degrees, and go back to while loop   //No, move on forward at set speed //If you’re surrounded and cannot exit send out a message through flashing LED's ________________________________________________________________________________________________________ I'm not asking for the code or for any of you to do all my stuff for me, I'm just asking for direction and resources. Thank You

Posted by Dark_Pheonix 2 years ago

As if I didn't have enough stress!

School sucks right now, have an A,B,C,& D, I'm stressed about that. But I come home today and I check my bank online and see that someone's used my debit card # to purchase $300 worth of soccer jerseys (WTF? SRSLY). SO I immediately call the bank (india) and tell them, guess what, since it's only pending they can't do anything, even though I alerted them, I have to wait until the money is stolen out of my account to file a fraud dispute, ridiculous. At least, I limit my liability to $50 by reporting it within two days (per, but it's a damned ass backward way to do it. BTW the banks solution, call the merchant,sigh, well their 800 number rang and rang, the other contact number went to voice mail, so they got a long detailed message. And of course, I cancelled my card, not at the banks suggestion. I has bad feeling about what a PITA this is going to turn into...

Posted by Tool Using Animal 10 years ago

Grid Tie and Induction Motors

Yes, I know it's nearly 3am on the east coast... but and idea struck me. So the idea is to feed small amounts of mechanical power into the power grid. Not necessarily run the meter backwards, but supplement power consumption.I've researched grid tie inverters - which are very expensive. For those wondering, a grid tie inverter is feeds mains power back into the grid by syncing phase angle and phase (no dead shorts :) ) and applying slightly higher voltage. They are very efficient and really not within a college student experiment budget :pSo I was thinking... Rather than go from mechanical to DC to AC to grid - go from mechanical to AC to grid VIA an induction motor. As a proof of concept, use a DC motor + battery to turn an induction motor. Plugged into the grid, in theory, should apply current. Oh, but the phase you say? How do you prevent a dead short?"I've thought of this -- before applying mechanical power - have the grid bring the induction motor up to speed. Then try to turn faster (apply a torque) with the DC motor, for example. In theory, the amount of extra power put into the grid will be related to the slip angle of the motor - which will also control the speed of the input (so you can't go over speed by too much).Keep in mind that this whole battery business is just a proof of concept sort of thing - I'm not talking perpetual motion or any hohaa craziness. In the end, the final mechanical input will be around 200 watts. I expect this to be very low efficiency (likely 50%ish), 100W isn't an answer to the energy issues - but it's an experiment. It's also not going to come even close to driving the meter backwards, but it should run (as supplement) my laptop + two to three 13w CFL's :DI think the theory is feasible -- the inspiration comes from flywheel driven UPS systems. An induction motor is driven while mains power is on to keep a flywheel in motion. When the power goes out, the FW drives the motor and feeds to local grid.I'm thinking of using a "low" rpm induction motor.... If I recall, ceiling fans are 16 pole? So that's 60Hz2*2/16=450rpm... Add ceiling fan motor to the list of things to hunt for :) Looking at the one above my head, it looks like it even has a nice bolt pattern for some sort of pulley shenanigans :DCan someone either throw some ice water on me and slap me for being an idiot -- or let me know if I've found a boat to Valhalla.Oh, and my apologies for dancing around the "mechanical input" details.... There's a reason for this, I promise :) In any case, insight and information is appreciated :)

Posted by trebuchet03 10 years ago