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Designing the circuit for robot

I am trying to design a floor cleaning robot that is also a obstacle avoiding robot. I want to use two tt dc motors for the wheels, a servo motor to control de ultrasonic sensor and a dc motor to rotate the sponge. Currently I have a Lafvin super starter kit that brings a L239D motor driver that will move the wheels but I am having trouble visualizing how to connect the DC motor and the servo motor. Can someone help with this circuit?

Question by prezgab    |  last reply

is there a way to make a soft object hard (e.g. soft plastic)? Answered

Some thing that you could brush on and let it harden?

Question by animan1    |  last reply

Fun uses for Reed Switches?

Reed switches are electro-mechanical devices that opens or closes a circuit when a megnetic field is present. They come in normally open and normally closed designs and range from the size of a grain of rice all the way up to several inches long. A relay, another electro-mechanical device, is comprised of a reed switch and an electromagnet trigger built into one housing. Common uses for reed switches (not counting relays which are used in virtually all electronic devices) include the 'pick ups' on bicycle computers and the sensors on window and door alarms. I just ordered a bunch of reed switches and I need your help in coming up with ideas for what to do with them. Post up your ideas for some things that could be made or modified to be triggered by a magnet coming in close proximity to a reed switch. Remember- the magnet does not have to touch the switch, just get close enough that the magnetic force trips the switch. The stranger and sillier your ideas are the better. Note: this is not a contest and there are no prizes. by posting an idea you are giving your consent for anyone who reads it to use your idea. Posts about integrating reed switches into knex firearms will be ignored (no offence, it's just not my cup of tea).

Topic by Handsome-Ryan    |  last reply

I have frequently tried to download an intractable however I am repeatedly asked for a verification to which is respond and nothing happens

I have frequently tried to download an intractable however I am repeatedly asked for a verification to which is respond and nothing happens. If you could let me know what is wrong that would be great. Thnx

Question by Dak Jack    |  last reply

sonic art

Please comment if u like it and tell me how i can improve sorry bout them bein sideways,in order we have sonic the hegehog,shadow the hegehog,and last but not least knuckles the echidna (edit i have now added neo metal sonic please leave a comment if u want me to draw anyone u want)

Topic by legomaster50    |  last reply


Yay, taking forever to do stuff! Haven't really accomplished anything big since the summer. Believe me, I keep fiddling around with my K'nex every now and then but things just don't quite work out and then I'll lose patience. Anyway, my current project is based on something I originally made just for fun as a refinement to a previous weapon I made just for fun. It was made to look realistic but otherwise was completely nonfunctional. I'm naming it the SMRI mostly just to be pronounced "samurai" but I'll figure out an acronym for it. Some of the features were a removable front sight, top and side rails designed for real/airsoft rail accessories and a bottom rail for K'nex accessories, and then a fake charging handle that locked back when the magazine is out of the weapon. It would then be triggered when inserting a fresh mag. The idea is that if it were a real weapon, I'd like a feature where on the last shot, the bolt is not only held open, but it automatically closes when a fresh magazine is in place. The overall style of the weapon probably resembles some real weapons, though unintentionally. My goal was to avoid the AK and AR-15 platform styles. So I designed the gun completely convinced I'd never make it shoot because it was too aesthetic-based. My main problem was designing the front of the gun to be open enough to allow a bullet to fly through it. Well, I modified the front sight set up just a bit to give enough space for a bullet to comfortably fly through. Overall I want to keep the design of the gun very similar, though I'll have to improve the stock, figure out the best way to incorporate a firing mechanism, and probably add a magazine lock. I was very pleased with the look of it, so I'm really hoping I can make this one shoot. I'll keep you posted. Of course classes, work, and social situations keep me occupied so I don't know how long it might take me.

Topic by TheDunkis    |  last reply

Rate my drawing!

Check it out! Constructive criticism please :P

Topic by FoxyPenguin94    |  last reply

Ultimate Pi Home Server

I'm new to linux and following through the instructables  for Pi home server. Everything is fine until I try to login to Webmin via ssh from windows 7 PC with `putty` using IP:12321 This lets me login to root @core but can't get the Webmin login screen. Any help much appreciated

Topic by Crocker7    |  last reply

What can I do with an old printer?

Wondering if and how I should harvest the innards for projects

Question by JCO72    |  last reply

Which microcontroller to use?

I was wanting to create a couple things using a programmable device, but without the bulk of an arduino board. I would prefer an SMD or qfp version. I am using JCBPCB to do my PCB production.

Question by Guacamolee    |  last reply

I'm a physics teacher and have an old bike in my possession. What are some neat toys I can make?

I am in need of some demonstrations which can be made from old bike parts. Or, neat things to enhance my classroom would work as well (gear clocks which rotate, etc).

Question    |  last reply


I found this in my dad's garage and have no idea what it is any help greatly appreciated

Question by Ridpathl    |  last reply

i'm collecting dead bic lighters and would like to make some sort of lamp shade or statue of some sort with them?

Any suggestions on any kind of project i could do with the lighters would great.

Question    |  last reply

Ventillator project

Hi everyoneI am a medical doctor with interest in 3d diy projects.Due to current corona epidemic i am planning to make a ventilator (if possible). I am looking for a pump which can be used for this purpose.I found something like ( but im open for suggestions.Thankyou

Question by rilyas    |  last reply

Homemade LCD?

I have been wondering this for some time now: How can I make my own lcd solution? I don't want anything that will be able to display a picture, what I'd like to do is make windows that can shade/unshade. It'd be only one pixel, so no fancy circuitry would be required.

Topic by guilty-black-kangaroo19    |  last reply

PDF downloads are available again!

UPDATE: PDF downloads are available again. (On 3/11/20 - please let us know if you run into issues!)Hi iblers! You may have noticed the "PDF download" button isn't working at the moment. We've taken it offline temporarily and we're working on a fix. I'll update this topic when PDFs are restored to normal. 💛

Topic by jessyratfink    |  last reply

Flavorful cooking with habanero peppers? Answered

I really like the flavor of habanero and have used various store-bought sauces in cooking. I'd like to try using habanero peppers in cooking, so I recently tried a raw habanero. The flavor was great, but the heat was overpowering. Is there something that can be added to raw habanero to bring out its flavor, but dilute its heat?

Question by vreinkymov    |  last reply

How can one make a water cleaner for a well using Titanium Dioxide and UV light? Answered

Hi, I have been looking into cleaning my well water at the source, rather than fed in into the lines. I have looked at making a simple ozone generator by purchasing one online and using a compressor to get it down 40 ft. Then I came across "silver bullet" and what intrigued me was that they produced hydrogen peroxide, which apparently is a a better bacteria killer, perhaps more stable. The reason that I want to kill bacteria and have it in the well at the source is because lots of iron bacteria and iron in my water plugging up my pump every so often is frustrating. This product looks promising, but costly, so researching this I found that they were using UV light, but normally UV light makes ozone with air. Then I dug deeper and then found out they are using a matrix made up of something similar to Titanium Dioxide (there are different forms, such as anatase and rutile which maybe more effective) so that when struck by proper UV light, it gives of an electron which will hit water vapor in air and split up water molecules to form OH- and H2O2 and some O3. So, one can buy TiO2 online, put it into a container that fits a UV lamp inside and blow compressed air through that and down the well, but the powder might get blown down the pipe. So how can one crystalize it around a cylindrical form that fits around a UV light to make it more efficient? I saw a similar post by Ian and he wants to use it for air cleaning, but gluing doesn't appeal to me as the glue itself might react with oxidants produced and give off other contaminants that I do not want in the water. So, can I use a type of glue that is safe around oxidants? Is TiO2 able to crystallize easily? ( I read that it doesn't dissolve in water well, which would rule out supersaturating water and crystallizing it that way) Any thoughts and suggestions?

Question by Hendrik0360    |  last reply

how can i make a toy plasma thruster that actually works???

I'd like to know how to make a plasma thruster like the one on that one youtube video. If you know how, or you were the one who put up that video, please put up an instructable on it and send me the link. You can reply to this post on my orangeboard on my profile, thanks...Youtube video: Plasma thruster:

Topic by nathanzhang    |  last reply

Where to find lightweight 12v batteries? Answered

I need a set of lightweight 12v batteries with a lot of power (15 ah or higher). I have an air conditioner that draws 3.33 amps and runs off 24 volts. My idea is a battery bank with two 12 volts in series to make 24v. I hope to run it ~5 hours off a full charge. I found these on eBay but they weigh 10lb each, which means 20lb for 2 of them. My goal is 10lb or less total weight: A single 15ah+ 24v would work but I cannot find one anywhere. Thanks!

Question by benbl19    |  last reply

I can't post a comment - get message " oops something went wrong!"

I logged in and out - no change. Is is me?

Question by chefspenser    |  last reply

How to make an FLIR Webcam? Answered

Can convert any Webcam into a FLIR camera, starting with the instructable to do an  IR webcam

Question by eflm    |  last reply

I want to merge 2 code in arduino to make them run together. Can anyone help me out??

The First code is for RFID Door lock, marked as 'Door_lock_2.0'And the second Code is for controlling Relay with Serial Inputs(By bluetooth), marked as 'sketch_mar24b'I have tried but the serial input in not working, but the rfid is working fine.

Topic by Rohit Kumar Saxena    |  last reply

Soldering copper to copper?

I'm just starting out but most of the instruction I've seen on soldering (jewelry) talks about flux, the solder itself, and a torch or soldering iron. When soldering copper to copper is there a special flux and solder to be used so that the solder doesn't look "silver"? Does it matter whether you use a torch or a soldering iron?

Question    |  last reply

Help to find an instructable

Hello all, please can someone help me find an instructable that was on here a while back! I’ve tried searching but to no avail.basically it was one which showed a picture of what my memory thinks was a dwarf/d&d; figure, possibly related to making a board game. It was made from laser cut plywood, and layered with coloured resin. The instructable had the plans for making it.does anyone remember seeing it?Thanks

Topic by Ouijatorium    |  last reply

Where is the best place online to buy k'nex pieces cheap, other than ebay? Answered

Not ebay, K? I know of several lego sites, but I havent heard of a k'nex site.

Question by Speedmite    |  last reply

What is the best course or way to learn Arduino and Raspberry Pi?

I am a student from India,Natioal Institute of Technology.I would like to learn Arduino and Raspberry Pi,but can find a good course or site to learn,please help me in finding a best course or way to learn Arduino and Raspberry Pi.

Question by Namratha3012    |  last reply

Motorized Monitor Lift idea - could I use a 775 motor (or 2) to power a lead screw lift?

Okay so I have a couple of extra 775 motors laying around (12V-36V, roughly 8A and 10K rpm). Also some cheap lead screws and some fittings, and I'm wondering if I can use them for sort of a crazy idea I'm formulating (which I'll explain more later if you're curious). I'm not sure if I've ever seen a lead screw actuator with BLDC motors, which makes sense because lead screws are for precision and that's what steppers are for. But I don't really need precision at all. I'm not sure which kind of motors they use in the actuators that are pre-built for things like this, they're usually hidden inside a housing. I've seen the DIY Perks build on YT where he used a 775 motor and a pulley system, and I realize pulleys are probably easier/better for a higher RPM motor. But I'm under the impression that BLDCs have more torque at lower speeds, and I want the whole lift assembly to be more compact than his if possible. Could my idea work if I was using a PWM controller to set the speed and some limit switches to shut it off? The load per monitor is about 10-15lb (5-7kg) and I have 8mm T8 lead screws. I basically have two of everything so if I figure out a lift that works well, I'd like to do a double monitor lift. Is this viable or no? Would it need reduction gears or something and just be too complicated? I'm about to mock something together and test it, but wanted to ask around first. I'm willing to scrap the lead screw idea if there's a better way. My crazy idea if anybody's interested: I want to build the most over-complicated electronics station/desk PC ever. (If you haven't heard of a desk PC, it's exactly what it sounds like - a PC inside a desk.) I'm thinking the PC portion will remain static, but it will have the hidden double monitor lift, an adjustable height KB + M surface, and an extra ATX PSU inside the desk. With a remotely wired access panel for all of the switches, some binding posts, volt/ammeter displays, etc. A very literal take on the "benchtop power supply." Oh and also maybe a hidden wireless charging surface somewhere in there too. I realize it will take wayyyyy more work than it's worth, but it would sorta be the culmination of several different skills I've been learning... but I'm still trying to learn some of them. There are two ways I can go about it. 1) If the lead screws work, I have more or less everything I need to build a version of it. But it would be a janky, bulky, heavy version with a lot of wood (I get tired of seeing wood, I like a more industrial look). 2) My dream come true would be to build the whole frame with 8020 aluminum, then use polycarbonate or something for the top. More expensive for sure, but it would be much more rigid and compact. I built my sim racing rig with 8020 a couple years ago. Love that stuff. And you can get it for close to 50% off from their ebay store.

Question by formVfunction  

Reverse cupping

I have a repair job I'm taking care of and need some advice. I have two small wooden panels that have warped pretty good. Dimensions are 6.5" w x 18" l. It's 1/4" thick. Also, it's rift sawn w. oak. Any ideas on reversing the warp.

Question by Benjamin Uminn    |  last reply

Forge refractory?

For a forge i am making i used permilite (or w/e it is called used in gardening) and furnace cement for the long will it take to cure?

Question by trf    |  last reply

What is a recipe for refractory cement in small amounts?

Https:// This has me wanting to make my own foundry, however i can't find how to make refractory cement, and nutandbolt doesn't list his own recipe. Alternatively, Where can I buy refractory cement in Australia?

Question by Nagarok    |  last reply

How to lower the DC voltage of a transformer. Answered

Hi, at last i have got a 45-0-45 transformer @5amps, but now i have a problem, the VDC output i am getting is 74vdc but my 400watt rms mono amp's maximum input VDC is 56vdc, so i don't think its a good idea to feed the 74vdc, so is there a way to lower the 74vdc, BTW please don't advice me to unwind the secondary coil because i am new to electronics and the transformer didn't come cheap, so i don't want to break it. i am using IN4007 diode and 4700uF 63V cap for the bridge rectifier. ​I just forgot to give some details on this topic. The transformer is to use with the 400watt rms mono amp. The amp has 8 MOSFETS side by side, 4 IRFP9240 and 4 IRFP240 and 6 transistors. BTW the transformer shows 45-0-45 VAC but when i test with a multimeter, the VAC is 53volts. Thank you. Regards.

Question by Lima79    |  last reply

Need Electromagnet help for table saw jig hold down.

Hey everybody,I'm making a table saw feed kit, that also required that I make a fence for it. I decided to make a fence out of wood, that I jointed square. So you folks can get an Idea, I have pictures, at least for the feed kit. And yes it does feed wood across the top of the table, like it should. I just haven't tested it with the blade running yet, but I'm sure it will work fine. It's likely I will write a comprehensive guide on how I did in the future.The issue I have is with the fence. When I clamp it on the end of the table saw it lifts up in the middle where I mounted the power feed. It's essential it remains flat to the table.Today, I made an electromagnet with a 5/8 bolt and 2 washers using 26 gauge winding wire, It GOT WAY TO HOT!I have seen door electromagnets, which leads to my question. If I use this type of magnet, will it still get extremely hot? I'm referring to the ones that have about 100lbs of hold down force, and are about 25 dollars.I'm aware that twist lock magnets are available, but they are way more expensive, plus the same power supply that drives the steppors can power the magnet.If someone can get me in the know I'd appreciate it.

Question by lostwarden    |  last reply

Just how far is "a block", anyway? Answered

When I read books based in America, distances are often related in "blocks". I have no mental image of "a block" - how far is it?  How long would it take to walk?

Question by Kiteman    |  last reply

How to build Montessori Pincer & Palmer Grasp Cylinders?

Does anyone have a good idea for how one would build Montessori Pincer & Palmer Grasp Cylinders?The basic block and cylinder seem pretty straight forward:Get some large dowel for the cylindersGet/cut some blocks that are slightly larger than the diameter of the dowelDrill the holes with a forstner bitBut how about the little knob on the pincer cylinder? I don't have a lathe so couldn't shape a single piece of dowel. I'm thinking of shaping the top from a bit of dowel by hand with a small hole and then gluing that to another.

Question by jasonpickensnz    |  last reply

Can you create an area for class to upload to Instructables?

Hi there,I am wondering if it is possible to create an area for my students to upload projects as a class? Any ideas or suggestions?

Topic by CarmelC    |  last reply

Laptop usb microphone Answered

How to make internal laptop microphone usb?

Question by Mr Qatanani    |  last reply


I made a knife out of a binder it is razor sharp should I post how to make it

Topic by Pat Sowers    |  last reply

I really like to get into beads, but I don't like grid-like sprites and organized beads, I like naturally layered stuff (Questions)

I fell in love with this piece is it sort of looks naturaly layered and with desorganized beads, do you know if they where glued on or just stiched?If I want to glue stuff like this to look good and last forever, with fake diamonds and stuff, what should I use?what kind of precautions should I use?I want to make different kind of gangsta blings and pendants with brooch like pendants and male chains out of naturally layered beads instead of stiched beads,but I don't know whether I should use mixed techiques on them like stiching and glueing!I'm really exited!

Question by DIAGONALLIS    |  last reply

CNC Laser Printer

Looking for someone to help me build a Laser printer. I want to go A0 size. Use Photographic negative, that is to use a developer and fixer liquid once the image is done. The image has to be B&W photographically with a sharp image quality. What sort of laser would allow me to have a high resolution? Thanks jag2x

Topic by jag2x    |  last reply

Multiple HDDs with Orange Pi NAS Expansion Board?

Hi. I'm a total NOOB with orange pi. I have never owned or used one, but I'd like to get started. I am trying to build a NAS(Network Attached Storage) to back up a few computers. I was planning on using the orange pi zero NAS Expansion Board, which has 1 SATA and 1 MSATA port. I would like to use at least 2 if not 3 or more SATA drives that I have lying around. Is there any way to do this with the Orange Pi? I think I saw somewhere that I cant use a SATA port multiplier like this is that true? I was also thinking of using an MSATA to SATA adapter like this so that I can use both the SATA and MSATA connectors, but that still only gives me 2 SATA connectors. The SATA and MSATA connectors on the expansion board are both connected through USB and they disable the onboard USB ports. Would it be better to just use a USB to SATA adaptor instead of the expansion board? Would one with multiple SATA ports work? What would be the best solution? Also, what would be the best OS for this? Thanks!

Question by Gadgets_and_Gear  

How can I make the most of my homemade stocks/broths?

Hello everyone,,I've been enjoying making vegetable broth/chicken stock over the past month or so, and it's made for some filling soups. However, I find that whatever I make soup with overpowers the broth so much that I can't appreciate the flavors of the broth. For example, I like to make a simple Minestrone. The broth tastes fantastic, but the potatoes and green beans I add to the soup leave no room for the broth to stand out. Is that just how soups work?That aside, I'd like to find other simple soup recipes so I can use all this stock I keep making..

Question by Devabhai    |  last reply

Some questions about my 12v wind turbine project

Hi! My name is Ashaz and I am 14. I am making a 12v wind turbine for a project at home. I am using ideas from various sites including YouTube and Instructables.I have some questions.1) I want to charge a 12v battery but want to prevent overcharging. Should I buy this to make sure it stops? It says I need a 220v input.2) If I was to buy the module, how do I use it? The instructions are a bit hard for me to understand.3) I want to keep costs low so should I go for a cheaper motor than the XD-3420?Thank you for your help in advance.

Question by AshazA    |  last reply

Instead of setting small gemstones by drilling holes on the metal, can I just mark them on a clay piece and glue them on the final metal piece?

Instead of setting small gemstones by drilling holes on the final metal piece, can I just lay out the grid of the stones and mark them by pressing them on a clay prototype basepiece with the typical stone "spike" or base of the gem pressed on the clay gently (maybe taking some clay off because the excess would go off to the sides) and then when I make the final metal piece from the mold I just glue the gemstones on the mold? Does this technique have a name?I think it will be more beautiful like that, can I do it this way?Instead of doing like this Youtube video, I press them on the clay prototype for gluing the jewels after on the respective fitting place on the metal mold.

Question by DIAGONALLIS    |  last reply

Airsoft gun?

I need a new airsoft gun. Under 100 dollars. Please suggest.

Question by weaponmaster1    |  last reply

Need help with a new motherboard

Planning to get a 3950x and was wondering if there will be new ones released with it. Also I have 2 motherboards in mind because I want an all black build. It's either the asus rog strix x570-f gaming or asus pro ws x570-ace rog strix is 290$ and the asus pro ws is 310$ So price doesnt really matter to me I like the look of both. I was just wondering which one is better performance-wise? I'm only gonna use a rog strix 1080 and 1-2 nvme m.2 ssds and 2 other regular ssds. 4x8gb corsair vengeance lpx 3600. Any help would be appreciated.

Topic by VoltarMendoza    |  last reply

HEY! I was trying to get 2 HC-SR04 to work together, such that i get the average of the 2 readings. but it doesnt work as expected and only displays 'OUT OF RANGE' on serial monitor. please help

This is my code:#define echo2 8#define trig2 9 #define LED1 2 // LED pin 2 #define echo 13 //ECHO pin 13 #define trig 10 //TRIG pin 10 float duration, distance, duration2, distance2, avg; //float command helps us to determine value of duration and distance in decimals void setup() { Serial.begin (9600); // setup ¯\_(ツ)_/¯ pinMode (echo, INPUT); pinMode (trig, OUTPUT); pinMode (LED1, OUTPUT);pinMode (echo2, INPUT);pinMode (trig2, OUTPUT);}void loop() { digitalWrite (LED1, LOW); digitalWrite (trig, LOW); digitalWrite (trig2, LOW); delayMicroseconds (2); digitalWrite (trig, HIGH); digitalWrite (trig2, HIGH); delayMicroseconds (10); digitalWrite (trig, LOW); digitalWrite (trig2, LOW);duration = pulseIn(echo ,HIGH); duration2 = pulseIn(echo2 , HIGH); distance = (duration/2) * 0.0343; distance2 = (duration2/2) * 0.0343; avg = (distance2/2 + distance/2); Serial.print ("Distance = "); if (avg>=400 || avg<=2) { // the formula of distance is duration of impulse divided by 2 multipled by speed of light in air meter per sec Serial.println ("OUT OF RANGE"); digitalWrite (LED1, HIGH); delay(50); digitalWrite(LED1,LOW); } else { Serial.print (avg); Serial.println("cm"); delay (150); } delay (150); }

Question by theHVguy    |  last reply

Run a hydraulic ram pump on no water drop? Answered

So I was wondering if you could run a hydraulic ram pump by digging down 3ft beside your well then pump water up about 50 feet at about a 40 degree incline. This way there would need to be no change in elevation between your ram pump and your well. Thanks!!

Question by camping crazy    |  last reply