USB Device not recognized :Fixed

One day I plugged a USB Device into PC or Laptop. Suddenly I got a Pop up message like “USB Device not recognized” .
I unplugged and inserted again my USB. But same result i got. I tried again and again.I didn't get anything new.

This issue can be caused if any of the following situations exist:

• The currently loaded USB driver has become unstable or corrupt
• Your PC requires an update for issues that may conflict with a USB external hard drive and Windows
• Windows may be missing other important updates hardware or software issues
• Your USB controllers may have become unstable or corrupt
• Your external drive may be entering selective suspend
• Your PC motherboard may need updated drivers

Then I searched on internet for this problem, then i got some solutions. I am going to share with you,
Method I:

• Right click mouse on My Computer icon.
• Click on Manage;

• Go to Device Manager 

• Uninstall all of the devices under USB Controllers. 
• Restarted the computer, reinstalled the USB drivers, 

But the problem still did not go away!No probs try another methods.

Method 2: 

• Turn off your computer using Shut Down or pressing the power button.
• Unplug it from the wall outlet. 
• Let it sit for about a minute 
• Plug it back in.

Method 3: 

• Disable USB selective suspend setting.
• This method prevents your USB external drive from powering down.
• Click the Start button, type power plan in the Search box, then click Choose a power plan.
• Next to your currently selected plan, click Change Plan Settings.
• Click Change advanced power settings.
• Click the box to expand USB Settings, then expand USB selective suspend settings.
• Click Plugged in, then click the drop down menu and select disabled.
• If you're using a laptop, click Battery, then click the drop down menu and select disabled.
• Click Apply, then click OK.

If this doesn't resolve your issue, proceed to Method 4.


Method 4:

• Run regedt32.exe and navigate to; 

HKEY_LOCAL_Machine\SYSTEM\CurrentControlSet\Services\Usb 

• Create the Usb key if it doesn't already exist. Under this key, create a new DWORD value called DisableSelectiveSuspend and give it a value of 1. 
• Then restart the PC. 

Method 5: 

• Install your motherboard's latest chipset drivers.
• This method updates your motherboard's chipset drivers, so your computer will recognize your USB external hard drive.
• Review your computer's documentation which should contain the name of the motherboard manufacturer.
• Visit your computer manufacturer's support website. For a list of computer manufacturers' support sites, visit: http://windows.microsoft.com/en-US/windows/help/contact-support/computer-manufacturers
• Navigate their website to find the appropriate drivers for your motherboard. For assistance, contact your computer manufacturer.

If your issue still exists, we recommend contacting Microsoft product support. For information on how to get assistance from Microsoft, please visit: http://support.microsoft.com/select/?LN=en-us&target=assistance&x=7&y=18

Related Post: Usage of USB Drive

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Usage of USB Drive : Must Read

Multiple use of USB
Use of USB Drive or Pendrive is not limited to transfer and store data.There are lots of usage of USB drive except data storing. Some of them are mentioned below.
1: Run portable applications

In addition to storing your data, you can run portable applications from a USB flash drive. For example, OpenOffice, which is a complete office suite that includes a word processor, spreadsheet, presentation tool, drawing package, and database, is available as a portable application. Mozilla Firefox and Thunderbird are also available as portable applications. When you combine the office suite with the ability to surf the Web and check email, you’ll be able to take your most vital computing applications with you wherever you go — right in your pocket.

If that’s not enough, you can choose other applications to install on your USB flash drive from PortableApps.com (Figure A). You can even install an entire prepackaged suite of applications that includes such things as an audio player, games, an antivirus utility, and a handy menu system.

Figure A

The PortableApps.com suite comes with a menu system to allow you to easily access your portable applications.

2: Boot an operating system

If you want to do more than just run your own applications, you might want to consider booting an entire operating system from your USB flash drive. You can boot either Windows or Linux from a USB flash drive; however, the process is not an exact science and you may be in for a technical adventure.
Check following links :
How to install windows 7 from usb flash
How to Put Windows 8 on a Flash Drive

3: Connect to a wireless network

If you have a wireless network, you can use the Wireless Network Setup Wizard in Windows XP or the Windows Connect Now (WCN) feature built into Vista to save wireless network configuration information to a USB flash drive. You can then use your drive to quickly and easily connect another computer or a WCN-compatible device, such as a router or printer, to your wireless network. To learn more about using the Wireless Network Setup Wizard, see the Help And Support Center, which is accessible from Windows XP’s Start menu. To learn more about using the Windows Connect Now feature, see Windows Help And Support, which is accessible from Windows Vista’s Start menu.

4: Create a password reset disk

A password reset disk can really come in handy if you forget the password to your user account on a Windows system that is not a part of a domain. If you find yourself in that situation, you can use the password reset disk to reset your password and quickly get back into your user account. In Windows Vista, you can use USB flash drive rather than a floppy disk as a password reset disk (Figure B). For details on how to do so, see the article Create a Vista password reset disk using a USB flash drive.

Figure B

You can use your USB flash drive as a password reset disk.

5: Boost performance

If you’re running Windows Vista, you can use a USB flash drive to speed up your system with the ReadyBoost technology. ReadyBoost can use the storage space on a USB Flash drive as an additional memory cache to aid the memory cache on your hard disk. And because flash memory is more responsive than a hard disk, with its physical moving parts, the memory cache provided by ReadyBoost can significantly improve system responsiveness.

Using ReadyBoost is easy. You just insert your USB flash drive into your Vista system and follow the onscreen prompts to configure and use ReadyBoost. If you want more details, check out the article How SuperFetch and ReadyBoost work together.

6: Manage it

If all you really want to do with your USB flash drive is transport data, and you’re running Windows XP, you can do so more efficiently with the Microsoft USB Flash Drive Manager (Figure C). Once you have installed this manager, you can easily copy files to and from your drive, back up and restore the entire flash drive to and from your hard disk, change the drive label, and even create an autorun.inf file to launch Drive Manager automatically when you plug in the drive. To learn more about and download the USB Flash Drive Manager visit the Microsoft TechNet Magazine site.

Figure C

The Microsoft USB Flash Drive Manager provides you with a host of features, such as drive backup.

7: Use it as an MP3 player

Would you like to be listening to music when you’re using a computer at the office, but you don’t have an MP3 player? If so, you can use a USB flash drive as an MP3 player along with Windows Media Player and a set of headphones. Just copy your MP3 files to your USB flash drive, plug it into your computer, and direct Windows Media Player to build a library of the songs on your drive. You can use all of Windows Media Player’s playback features, such as playlists and favorites, to easily customize your music listening experience. And best of all, you won’t have to worry about running low on battery power.

8: Password-protect it

If you use a USB flash drive to transport sensitive data that you would prefer to protect from prying eyes, should you lose the drive, Rohos Mini Drive (Figure D) can safeguard that data. This security tool allows you to create a secret partition on the drive and then password-protect/encrypt that partition, thus protecting any documents you copy to that partition via the utility’s file manager. You can download (and read a review of) Rohos Mini Drive at Download.com.

Figure D

Using Rohos Mini Drive, you can secure sensitive files on your USB flash drive.

9: Run a Web site from it

If you are a Web developer, you may be interested to know that with Server2Go, you can easily run a Web server that supports Apache, PHP, MySQL, and Perl right from a USB flash drive. You can use Server2Go right out of the box without any installation. It runs on all versions of Windows, supports most common browsers, and is completely free. To a developer, the benefits of having a portable Web server on a USB drive are numerous. For example, imagine being able to carry a live Web site demo into a sales pitch meeting. For more information about this package, visit the Server2Go site.

10: Lock your PC

Have you ever seen a movie in which a person in some secret government installation simply inserts and removes a card to log in and log out of a PC? If you thought that idea was cool, you’ll definitely want to investigate Predator (Figure E). Once installed and configured, this little freeware utility will allow you to turn a USB flash drive into a key you can use to lock and unlock your computer.

Figure E

With Predator, you can use a USB flash drive as a key to lock and unlock your computer.

While the USB flash drive is connected to your computer, everything works as it normally would. Once you remove the USB flash drive, your computer is locked down — the keyboard and mouse are disabled and the screen darkens. To unlock your computer, you just plug in the USB flash drive and the computer will be unlocked and you can begin using it. To learn more about Predator, and/or to download it, visit the developer’s Web site.

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How to prevent your pen drive from getting infected with Virus ?

Friends many of your PC/laptop's normally gets virus because of Pen Drives or USB devices (Even PC's who are not connected to network ). Some Virus like Ravmon Virus , Heap41a worm which are not detected by anti virus normally spreads mostly by the Pen Drives . In such a case what can you do to prevent your PC from getting infected with Virus that spreads through USB devices or Pen Drives ?

You can protect your PC by just following the simple steps below . It won't take much time.

* Connect your Pen Drive or USB drive to your computer .
* Now a dialogue window will popup asking you to choose among the options as shown in the figure.

* Don't choose any of them , Just simply click Cancel .
* Now go to Start--> Run and type cmd to open the Command Promt window .
* Now go to My Computer and Check the Drive letter of your USB drive or Pen Drive. ( E.g. If it is written Kingston (I , then I: will be the drive letter .)
* In the Command Window ( cmd ) , type the drive letter: and Hit Enter .
* Now type dir/w/o/a/p and Hit Enter.
* You will get a list of files . In the list , search if anyone of the following do exist .

1. Autorun.inf
2. New Folder.exe
3. Bha.vbs
4. Iexplore.vbs
5. Info.exe
6. New_Folder.exe
7. Ravmon.exe
8. RVHost.exe or any other files with .exe Extension .

* If you find any one of the files above , Run the command attrib -h -r -s -a *.* and Hit Enter.
* Now Delete each File using the following Command del filename ( E.g del autorun.inf ) .
* That's it . Now just scan your USB drive with the anti virus you have to ensure that you made your Pen Drive free of Virus .

Now Unplug your Pen Drive or USB device and Plug it again to your Laptop/PC . Before removing your Pen Drive from others Computer , Don't forget to search for .exe files using the Windows search and remove them .

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How to make USB password generator for Windows

I made a device that stores a previously generated password in EEPROM and inputs it to PC every time the device is connected.


Main Parts:

Circuit Diagram:

The device implements the USB boot HID keyboard protocol so once plugged in, the device can receive keyboard LED state changes (caps lock, num lock, scroll lock), which are used in the firmware to trigger new password generation (four LED toggle messages, i.e. four caps lock presses).

How to Fix circuit in USB :

Randomness for the generated password is also taken from LED state change timings - ATtiny85 timer is left running and every time an additional state change happens, lower 6 bits in TCNT0 are used to add one character to the password - so for a new 10-character password (default setting), a total of 4+10 caps lock presses generate a new password, which is stored in EEPROM.

Download Source Code and Full Documentation .

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How To Make USB write protected

I came to know of this trick of write protecting the drive so that I can safely copy things I want without the worry of virus being copied on my USB drive. Although you won’t be able to write any thing on your pen drive, its still very useful in case you want something to copy from your pen drive and don’t want to get infected. Before proceeding I must tell you that playing with the registry can be harmful for your Operating System (OS) and I advise you to take a backup of your registry in case anything goes wrong. Read how to Backup Windows Registry.

This trick works only on XP SP2 and you need to have administrator privileges.
Follow these steps:

• Open Registry Editor by Start > Run.
• Type in regedit.

• Browse to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\
• Locate the sub-key StorageDevicePolicies. If it doesn’t exist then create it first. 
• Create a new key under Control by right clicking on it so that you don’t create it elsewhere by mistake (as shown in the above screenshot).
• Right click in the blank area of the sub key you just created and create a new DWORD value by the name WriteProtect.
• Double-click it and set the value data as 1 (and 0 for disabling it).
• Click OK, close the Registry Editor and restart the PC.

The drawback of this trick is that you need to remember this trick by yourself and you need to restart the PC after applying this trick.

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Put a background to your USB flashdrive

Thought you would also be fascinated like me on this one. ...........
Step 1:
Copy this code into notepad (copy and paste), then save it as "desktop.ini"
CODE
[.ShellClassInfo]
IconFile=%SystemRoot%\system32\SHELL32.dll
IconIndex=127
ConfirmFileOp=0
[{BE098140-A513-11D0-A3A4-00C04FD706EC}]
Attributes=1
IconArea_Image="your_picture.jpg"
IconArea_Text="0xFFFFFF"
VeBRA sources - don't delete the tag above, it's there for XXXXX purposes -
[ExtShellFolderViews]
{BE098140-A513-11D0-A3A4-00C04FD706EC}={BE098140-A513-11D0-A3A4-00C04FD706EC}
{5984FFE0-28D4-11CF-AE66-08002B2E1262}={5984FFE0-28D4-11CF-AE66-08002B2E1262}
[{5984FFE0-28D4-11CF-AE66-08002B2E1262}]
PersistMoniker=Folder.htt
PersistMonikerPreview=%WebDir%\folder.bmp
Step 2:
Put "desktop.ini" file onto your flash drive and replace "your_picture" with the
name of the picture you want to use leaving the .jpg extension the same.
Step 3:
Now copy the picture that you want to use onto your flash drive.
Step 4:
Refresh (F5) or Go back to My Computer and open your flash drive again ..and enjoy with new background... .....

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How to make Supercapacitor USB Light

For those who never heard about supercapacitor, you can check for more info about supercapacitor here . Supercapacitor is basically a capacitor with very high capacity, and the capacity rating is normally around few Farads. With the “super” capacity, it basically can store a lot of charge, and I am going to use the “super” capacity to store charges for a 5mm LED. Let’s see how long will the 5mm LED last.

Step 1Components Needed

The components you will need for this project is basically a supercapacitor (I am using 5.5V 0.1F supercapacitor which I bought from Farnell), a White LED, a 1K Ohm resistor and a USB male connector (I get this from an broken pendrive).

Step 2Supercapacitor Polarity

Make sure you know the polarity of the supercapacitor, or refer to its datasheet

Step 3Soldering

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The first step is to cut the 2nd and 3rd pin of the USB male connector, we will need only the 1st and 4th pin (5V and 0V pin).

Then solder the negative pin of the supercapacitor to the 4th (0V) pin of the USB male connector.

Now, try to connect the positive pin of the supercapacitor to the 1st pin (5V). For the connection I am using a resistor leg.

Step 4Soldering

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Next, connect the positive pin of the White LED to the 1st pin (5V) of the USB male connector.

Finally, connect a 1K resistor from the negative pin of White LED to the 4th pin (0V) of the USB male connector.

Step 5Schematic

Please check the diagram below for the complete schematic. You are actually free to use higher Farad supercapacitor, but voltage rating must be larger or equal to 5V, and you can have your creative way to connect all the components together.

Step 6Testing

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Now, plug it to your computer for around 10-30 seconds to charge up the supercapacitor.

You should see the White LED turned on (if it doesn’t turned on, there are some mistake in the connection), then after 10-30 second, you can unplug it and you should have around 10 minutes of the LED light.

Step 7Circuit Update

Circuit Update (6 Oct 2010)

I made some changes to the circuit, adding another resistor to limit the current consumption from USB port, and an ON/OFF switch to control the white LED.

The circuitry is simple, when you plug it into PC, the USB port will start charging the Supercapacitor, and there is a 10Ohm resistor (R1) limiting the current from USB port to 5V/10Ohm = 500mA maximum, but the R1 will also slow down the charging time. For large capacitance Supercap, you might need to let it charge for around 1 to 2 minutes. At the LED side, the S1 will let you turn ON or OFF the LED, and the 1KOhm resistor (R2) is to limit the current for the LED. If you use smaller value for R2, like 330Ohm, it will increase the brightness of LED but will also reduce the operating time of the LED for one charge. By using larger value for R2, you will increase the operating time, but reducing the brightness. I found 1K to be the balance value for the brightness and operating time.
Talking about the brightness and the operating time balance, I created another circuit that let you choose 3 level of brightness.

Step 8Circuit Update

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In this circuit, the charging and USB port part is still the same, but I add in S2 and R3 at the LED side. So, the S1 and R2 will still function like the previous one, that by switching on S1, you will get the 1KOhm resistor brightness. By adding S2 and R3, it means that if you switch on S2, you will get 330Ohm brightness, which is brighter than 1KOhm brightness, because the resistor that limiting the LED current is now smaller and higher current on the LED means higher brightness. I say you will have 3 level brightness, so, the third level brightness is by switching ON S1 and S2 at the same time.
When S1 and S2 is being switch ON, the R2 and R3 form a parallel pattern, and you need some calculation to get the total resistance for the White LED.


The total resistance from the parallel of R2 and R3:
1/R = 1/R2 + 1/R3
R = 1 / ( 1/R2 +1/R3 )
R = 248.12Ohm
So, the total resistance at the White LED if you turn ON both S1 and S2 is 248.12Ohm which is 3rd level of brightness for the White LED.
- 1st level (S1 ON) – 1KOhm Brightness
- 2nd level (S2 ON) – 330Ohm Brightness
- 3rd level (S1 and S2 ON) – 248.12Ohm Brightness

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How to make Breath powered USB charger

Are you breathing? Do you have a gadget that can be charged via a USB port? Well if you answered yes to both, then you are in luck. This instructable shows how to make a device that will charge your USB-capable devices while you do what you do best. Breathe. Using some parts scavenged from an old CD-ROM drive, a simple electronic circuit, and a few rubber bands you will soon be huffing and puffing your way to fully-charged pseudo-useful electronic gadget nirvana.

Step 1Introduction and Step 1

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This project requires a wide range of "maker" skills, such as PCB board manufacture, dismantling of electronics, cutting and drilling plastics, mixing epoxy, designing a gear train, kludging together a bunch of parts, bending paper clips, and risking the well being of your ever so expensive phone, camera, or PDA. All in all, good fun.

Since everyone will have a different collection of junk parts to build this from, I will just give you a detailed overview of how I went about it and you can apply these ramblings to your own project. Which will consist loosely of four steps.

• Scrounge up some suitable parts for the generator
• Build the charger circuit
• Assemble the generator, thorax coupler, and mechanical return
• Connect the charger circuit, and test

Step 1:

I had about four old CDROM drives hanging around and took apart a few of them to see what cool parts were inside. Turns out there are lots of cool motors, gears, and other parts inside that fully validate my insistence of keeping such crap laying around. Seeing the gear trains inside these units used for opening the tray gave me the idea for this project. The small low-torque, high-RPM motor is linked to the tray via a gear train that has a final ratio of about 20:1 Previously I had been using a parallel array of tiny pager motors to generate electricity from breathing (see below) but the linear travel from your chest expansion is not that great (around an inch) so in order to generate useful voltages you had to really huff and puff.

Anyway, tear into those CDROM drives, which you can find at pretty much any garage sale, thrift store, or landfill. The pic below shows the results. Lots of potential projects in there. For now, we are only interested in the plastic gears and the motors for opening the tray and/or moving the laser carriage.

Look over the various gears and drives and try to visualize a way to add additional gears to increase the gear ratio, or how to add another motor in series. You want to minimize the changes to the gear train. Alternatively you can just scavenge all the gears and build your gearbox up from scratch.

You are also going to need at least one motor with a small gear or pulley on it so that you can connect it to the gear train. The motors in the CDROM drive are typically simple permanent magnet DC motors designed to run on 5V, except for the spindle motor, which you don't want to use anyway.

At this point you also want to think about what you are going to use for a strap to go around your chest. An old belt, some webbing, an old shoelace, a name badge strap, or anything that will fit around you comfortably without any stretch to it. You want all the expansion to take place in your linear generator. Any stretch that occurs in your thorax coupler will be wasted energy.

Step 2Build the charger circuit

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The charger circuit is pretty simple. It consists of:

1. A diode bridge to turn the AC voltage from the generator into rectified DC.
2. A rechargeable battery to level out the voltage and hold excess generated power when nothing is hooked to the USB port. You could use a big capacitor too, but batteries offer a more predictable voltage level.
3. A boost converter to bring the low voltage up to 5VDC for USB charging
4. A USB plug.

I've drawn up the circuit in EAGLE, a program that I highly recommend. You can download it for free from cadsoft.de . The schematic and single layer board layout are attached. The actual use of EAGLE and the board manufacture are beyond the scope of this instructable. Many great instructables are out there to cover these topics.
The parts list for the charger circuit (quantities in bold):

1. 1x L6920 Adjustable output step up DC converter (1V minimum input, Datasheet here ) Digikey# 497-4593-1-ND.
2. 4x 1N4148 switching diodes (I used tiny SOD523 smds, but you can sub in what you have handy) Digikey# 1N4148WTDICT-ND.
3. 2x 10uF ceramic or other low ESR capacitors (I used 1206 smds) Digikey# 39901299-1-ND.
4. 2x 100k thin film resistors Digikey# P100kFCT-ND.
5. 1x 10uH wirewound inductor Digikey# 490-2519-1-ND.
6. 1x USB female Type A smd connector Digikey# AE9924-ND.

Below you can see the schematic and board files, and jpegs of them as well. The tough part is making a good PCB in your kitchen that has traces small enough for the TSSOP package of the L6920. As you can see in the pic, I made 4 boards at once since each is so small.


The trick to putting it together is to start in the middle and move your way out, begin with the L6920, and add the SMD discretes as you go. A pair of tweezers is essential, along with good eyes or a magnifying glass, bright light, and a steady hand. Don't worry about getting too much solder in there, use your solder wick to clean up any accidents, and check your work with a multimeter after every step. Practice makes perfect.

breath_gen_V1.sch97 KB

breath_gen_V1.brd8 KB

Note:
After Downloading above file in .temp extension, Rename it with appropriate extensions (.sch and .brd)

Step 3Build the generator

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Now you need to make the generator. You should play around with the gears and motors until you get a satisfactory arrangement. You will want to use a multimeter on the motor while turning the gears to see how much voltage you are getting. You want to get in the 2-3 volt range while moving the linear gear slowly about an inch in travel. When setting up the gears, you want to use the ones that have a large gear molded with a smaller gear. Stacked in series these will give you a good gear ratio as shown in the drawing. (ignore the fact that the teeth are the wrong size in the drawing, I was too lazy to redraw with matching tooth pitch) You should shoot for somewhere in the 25-50:1 range. More is better but eventually the losses in the gear train pile up and it get too hard to turn the motor and the gears will strip.

One of the keys is to find a way to use the linear gears on the CD tray or other piece to turn your breathing motion into rotation of the DC motor. I included a pic of another prototype version of the CD drive generator where you can see the linear tray gear clearly. Also visible are the cut marks in the plastic. This prototype was also capable of lighting the LED array pictured. Don't be afraid to chop this thing up to suit your needs.

In the other pic the DC motor is mounted in place in the plastic of the drive I cannibalized. Near this was a linear slider that I used to couple the breathing motion to the gear train. I also added another gear (see pic) to the drive train in order to increase the ratio and to allow mounting another motor in the future to increase output. The main challenge is to effectively get the breathing effort translated into rotation of the motor efficiently.

Step 4Put it all together and test it out

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Once you have a satisfactory generator setup, then you want to connect the generator to the charge circuit, insert the battery, and use your multimeter to test the output voltage at the USB port. If you don't see 5V then there is a problem. Fix it before plugging your pricey gadget into the USB port.


Below you can see my assembled breath powered USB generator in all its glory, top and bottom. You can see the rubber band used for return, along with the linear gear carriage, the strap and the paper clip I used to connect the linear gear to the strap. The key here is to have all motion transferred to the linear gear so you want the strap and connection method to be stiff with no give. The strength of the rubber band or spring return is up to you. My half-assed experiments indicate that you can pretty much handle a 1N force without feeling too labored in your breathing. Ideally you want as small a rubber band as will return the linear gear to the starting position when you exhale. If you get enough generating capacity either through high gear ratio, extra motors, or a bigger motor, then you will need a bigger spring return. Essentially you are storing mechanical energy during your inhalation that is used to turn the generator on the exhalation so that you can generate on both push and pull. You need the diode bridge to successfully take advantage.


So I strapped on this monstrosity and hooked it up to my trusty data acquisition box from DataQ . Attached is the voltage plot output of the generator before step-up conversion to the 5V USB. Basically the battery runs the step up converter and the breath generator charges the battery. In the plot you can see the leveling effect of the battery, with the voltage spikes when I was breathing. Actually I was approaching hyperventilation, but in the name of science. The results can be seen in the photo of the phone charging. One thing to mention is that I had to modify a USB cable to get the RAZR to charge as detailed on this website . I don't have any solid numbers on the power I was generating, I haven't come up with a good way to measure that yet.


Typical resting metabolism is on the order of 50-75W of which a substantial portion is due to breathing effort (I have seen north of 50%). So if we assume 25W continuous energy used for breathing, it seems reasonable that we could increase that 4% to harvest 1W for charging a cell phone. Based on my cell phone, and these assumptions it would take about 3 hours to charge the 3.7V 800mAh battery. Assuming 100% efficiency.


Sadly, based on the few measurements I was able to make, the breathing generator I built is putting out more like 50mW. Way to breathe no breath. It would charge the phone, but the NiMH battery would be doing most of the work until it was drained. Then you would have to breath for a day or so to recharge the NiMH battery. You were planning on doing it anyway right? So there is room for improvement. One area I am looking into is using carbon nanotubes and polyurethane to make an electroactive polymer generator . This is the type of technology that is being used to make boot-strike generators for the military .


Future improvements could get this device into the 1W range. Specifically, using a better DC motor (higher voltage per rev) and custom building the drivetrain to be more comfortable and better coupling to breathing motion.


I have been working on these types of devices in my kitchen/workshop for a while and would like to make this all public so others can get on board. Feel free to contact me with questions or for discussion. As the bard said, "and the domestication of the dog continued unabated."

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