Wednesday, 21 March 2012

How To Build A Robot

The best way to learn about robotics is to build and program your own robot. This can involve buying many different parts from a range of suppliers, or you could take a simpler route with a DIY kit.
We’ve used the £75 Deluxe junkBot from RobotBits. A £65 Basic junkBot is also available, but this model requires you to do some soldering work on the motherboard and supply your own wheels and castor.
Here, we describe how to fit together the various components in the kit. Even those with no engineering experience will be able to follow our instructions, using only a set of screwdrivers and a drill. It should take little more than an hour or two to build your own junkBot robot.
Left to its own devices, your junkBot isn’t capable of much. Just like a PC, it needs to be programmed using software in order to do anything useful. Unlike PC software, though, which mostly writes information to the computer’s screen, the junkBot’s software drives the motors that are connected to its wheels and uses an infrared sensor to detect nearby obstructions.
To complete our introduction to robotics, we’ll show you how to download a sample program to your completed junkBot. This can be modified to alter the robot’s behaviour.
This is just the start, though: the sophistication of your junkBot’s behaviour is limited only by your imagination and how much time you’re prepared to take in honing your programming skills and developing the necessary software. Persevere, and you’ll be amazed at how much you can achieve with such a simple, low-cost kit.
Step 1. The junkBot kit doesn’t include a chassis. You don’t want something that’s so heavy it’ll overload the motors, nor so flimsy it’ll collapse during use. We suggest a plastic box that’s large enough to house the parts and long enough to be stable. We bought a 1.5-litre tub for £1.25 at our local supermarket.
Robot 1
Step 2. Attach a wheel to the axle of each servo motor (black boxes with black/white/red leads). The wheels should push in easily if they’re the right way round; secure them with the small black screws. Attach each motor to the bottom of the chassis using the double-sided sticky pads provided. Fix the castor to the back, too.
Robot 2
Step 3. Plug the Mini-IO Shield circuit board into the Arduino Uno circuit board and secure it using the plastic spacer and screw. The Arduino Uno board will form the brains of your robot. The Mini-IO Shield provides an interface between the Arduino Uno and the junkBot’s motors and sensor.
Robot 3
Step 4. Fix the Arduino Uno/Mini-IO Shield assembly to the inside of the chassis using the three metal stand-off pillars and the six screws provided. Position it near the front, leaving space for the battery holder behind. You’ll need to make three small holes in the base of the chassis. If you don’t have a drill, use the point of a pair of scissors (carefully).
Robot 4
Step 5. Attach the distance sensor to the front of the chassis (the wheel end). The two black shiny spheres (an infrared LED and an infrared detector) should point forwards. Since there’s no space for adhesive pads, you’ll need to use nuts and bolts. Make sure it’s not pointing downwards, packing it out if necessary. Plug in its lead.
Robot 5
Step 6. Insert six AA batteries into the battery holder. Connect the battery lead to the battery holder and use the two pairs of self-adhesive Velcro strip to attach the battery holder to the inside of the chassis. Position the battery holder near the back of the chassis to keep the weight balanced.
Robot 6

Step 7. The motors and distance sensor are mounted on the outside of the chassis, so you’ll have to make some holes for the wiring to make a neat job. Using a drill (or scissors), make holes close to where the lead exits each of the motors and another where the lead exits the distance sensor. Pass the leads through the holes.
Robot 7
Step 8. Plug the lead from the lefthand motor into channel 0 of the Mini-IO Shield, the lead from the righthand motor into channel 1, and the lead from the distance sensor into channel 2. In each case, ensure the white wire is the closest to the outer edge of the Arduino Uno board. Use cable ties to tidy up the wiring.
Robot 8
Step 9. Download the IDE for the Arduino board. Extract the files from the Zip archive, preserving the folder structure, then follow the instructions to install the driver. In Windows 7 you’ll find this under ‘Other Devices’; it’ll move to Ports when the driver has been installed. Make a note of its COM number.
Robot 9
Step 10. Start up the IDE by double-clicking the Arduino application. Download the sample code from, then open it in the IDE by selecting Open from the File menu. Select Board from the Tools menu and choose ‘Arduino Uno’. Now compile the program using ‘Verify/Compile’ from the Sketch menu.
Robot 10
Step 11. If it’s not still connected from Step 9, connect the junkBot’s Arduino Uno board to your PC using the USB cable. Select ‘Serial Port’ from the Tools menu and choose the COM port that you noted in Step 9. Select ‘Upload to Board’ from the File menu. When the ‘Done uploading’ message appears, disconnect the USB lead.
Robot 11
Step 12. Plug the lead from the battery pack into the Uno board and place the junkBot on the floor facing a wall. It should move forward until it reaches the wall, then turn around and proceed until it finds another wall. If it moves backwards, the two motors have been connected the two wrong way around.
Robot 12
Step 13. Now try modifying the sample code. Edit it using a text editor, such as EditPad Lite. Enter the code in the screenshot in place of the code starting with ‘while(!front_bump())’. The ends of some lines have scrolled off the screen, but anything after a // is a comment and won’t affect operation.
Robot 13
Step 14. Repeat Steps 10, 11 and 12 with this new code. The junkBot should behave as before, but when it reaches a wall it will now stop, back up and turn around. You can now start your own voyage of discovery by altering the software further or writing your own code from scratch.
Robot 14

How To Reset Blackberry PlayBook To Factory Settings

Performing a factory reset can be useful in a number of situations and for different reasons. You might want to sell the tablet and make sure all your personal data is removed from the device beforehand. It can also be useful if your device has become too clogged up with apps, files and different accounts which may be compromising the performance.
Follow out step by step guide to resetting your BlackBerry Playbook
Note: Before resetting the PlayBook, make sure sure backup any data you wish to keep. Apps can be downloaded again after the reset.
Step One
Navigate to the Setting s menu. Do this by swiping downwards from the bezel above the screen or tapping the cog icon in the top right hand corner of the home screen.
Factory reset a BlackBerry PlayBook
Step Two
Scroll down the Setting menu and click on Security.
Factory reset a BlackBerry PlayBook Menu
Step Three
Within the Security pane on the right, click on the Security Wipe option.
Factory reset a BlackBerry PlayBook Security
Step Four
Type the word ‘blackberry’ into the text box and click Wipe Data. The PlayBook will carry out the full factory reset and reboot the tablet ready for use again.

Friday, 16 March 2012

Learn How To Jailbreak An IPhone

We'll focus on the iPhone 4 here, as the warranty will have expired on most handsets. The process is largely the same for other models (including iPod touches and iPad), so the principles still apply.
Before you start, back up your device in iTunes or iCloud. To force a backup in iTunes, right-click on your device in the list on the left and click Back Up.

It's also important to understand the difference between tethered and untethered jailbreaks. The former is something you don't want, as you'll need to connect your phone to a computer in order to reboot it. An untethered jailbreak means you can reboot the phone without consequence: everything will still work afterwards.

Also bear in mind that you must not update your iPhone's software when Apple releases an update. If you do so, it will overwrite the jailbreak and delete all the custom apps you've installed and settings you've made.
The following instructions work for devices running firmware 5.0.1. There is already an updated version of Redsn0w available for 5.1, but this is tethered, so you'll probably want to wait for an untethered version. If you want to jailbreak an Apple A5-powered device such as the iPhone 4S or iPad 2, you'll need Absinthe rather than Redsn0w.

We'll be using Redsn0w as it has always worked flawlessly for us, but there are a variety of other tools available. Download Redsn0w for Windows. Extract the files to a folder and then right-click on the Redsn0w application and choose Run as administrator. When the application launches, click the Jailbreak button.


Connect your iPhone (4 or 3GS) or fourth-generation iPod touch to your computer and power it off by holding the power button until the slider appears. Wait until the phone has completely shut down before proceeding. Redsn0w looks for your device in DFU recovery mode. This is how to enter it:
  1. 1.    Press and hold the power button for 3 seconds
  2. 2.    Continue to hold the power button and press and hold the Home button for 10 seconds. The Apple logo should disappear during this step.
  3. 3.    Release the power button and continue to hold the Home button until your device is in recovery mode. Your computer might detect new hardware or iTunes might launch and warn you that it has found a device in DFU mode.

If you don't manage to press the buttons at the right times, don't worry: just close Redsn0w and start again. If your iPhone or iPod locks up, press and hold the power and home buttons simultaneously until it restarts.
Installing Jailbreak

Once in DFU mode Redsn0w will interrogate your device and ensure it's compatible. When complete, you will be presented with some options. Tick the box to install Cydia and click Next. The jailbreaking process is automatic, and you'll see commands scrolling down your device's screen and a pineapple logo - this is all normal. When your phone finally restarts, unlock it and check that the Cydia app is there: this is the only outward sign that your device is jailbroken.
Cydia app

Monday, 12 March 2012

How to Download Free E-Books

Before you start worrying about the cost of buying eBooks. it's worth remembering that there are a number of places you can download eBooks for free and its legal.

There are  a number of website sites such as, Oboko and Project Gutenberg that offer free out-of-copyright eBooks that can be downloaded. Project Gutenberg houses 36,000 free eBooks and includes links to a total of 100,000 hosted on other sites meanwhile offers a selection of free Harlequin romances and a range of cut-price titles. The only snag here is they can't be downloaded directly to your device using a Wi-Fi or 3G connection. You'll have to download them to your PC and then transfer to your eReader by connecting the device to your computer via its bundled USB cable. Although has an app for Google Android and iOS devices which means you can download the eBooks straight to your mobile phone.

Alternatively, lets you download digital extracts of books so you can see if you like the book before shelling out for it. It's also worth visiting specific author or publisher websites and signing up for newsletters from them, as sometimes cheap or free eBooks are offered, or even follow them on Twitter. WH Smith offers a handful off free ebooks, along with a selection of 'Bargain eBooks' which start from 99p and certainly won't break the bank. Waterstones also offers cheap eBooks


Things You Should Know About The New IPad3

On March 8, 2012, Apple introduced its "new iPad" with great expectation and fanfare. It was generally greeted with a loud "meh." And those people are missing an important insight.
For example, CNN reported "REVIEW: NEW IPAD NEITHER DUD NOR 'REVOLUTION.' On first glance, the new, never-to-be-actually-named iPad is exactly the same as its predecessor: Same size, same price, same colors."

Polishing a Great Product

with the new iPad, there isn't much more to bring to a great design other than a noticeable increase in display resolution and initially invisible increased compute power and G4 cellular network speed. And you get all of this for the same price as the last generation.
This trend was initially observed by Moore's law in 1965 - technology doubles in capability every year (plus or minus) for the same price. (For a great overview, check out Moore's Law on Wikipedia).

Most Users Miss the Value

If a tablet just replaces books, magazines, and TV screens, then advances in network speed and compute power get overlooked or ignored.
Most iPads get used as an entertainment device. These users won't think that the new iPad has much value because they don't believe that there is any advantage to them.
And that's where most people ignore and miss out on what's really happening. The reality is that higher quality video and a better resolution display demands more compute power and network bandwidth. And this offers much more capability that only a few will recognize and capitalize.

Exponential Improvements

The iPad 2 is twice as powerful as its predecessor in terms of compute power and networking speed. And the new iPad is twice as powerful again. This makes the new iPad four times more powerful then the original.
There is no reason to think that the next generation iPad won't be twice as powerful again. So in five years, the "iPad 8" will be 128 times more powerful than the original.

The Power User's Advantage

Power users will find ways to use that to their advantage. For example, if a Google search occurs in half the time, you can accomplish more. If voice commands -- three times faster than typing -- improves productivity, you become freed to do other things. If you can see more on the higher-resolution screen, then you can take in more information in a single page, speeding your tasks.
If you really want to benefit from the exponential technology curve, figure out how to use the rapidly advancing compute and network power of devices like the iPad. Get ahead of the curve with your ideas and products. In the next 24 months, you'll be able to bring to market products that 99.9% of people can't even imagine right now.

Saturday, 10 March 2012

How To Create Iphone Apps

You may have thought that not everyone could create iPhone apps, but you would be wrong. You have seen how some guy from nowhere USA, got wealthy by creating an app and you think you have a great idea of your own but that you do not have to skills to make it a reality. The truth is that it does not take a rocket scientist to create iPhone apps that will sell and be useful. If you have ever thought that you could improve on an existing app or make a totally new one keep reading to find out how.

The thing that frightens most people that want to create iPhone apps is the programming and graphics. They think that since they have no experience with these that making an app for iPhone or other mobile devices will be difficult, nothing could be farther from the truth. Take the app "Angry Birds"; a professional team of programmers created it but one app that is just as popular was created by 14 year old. That's right a kid created Bubble saga and it is more popular by far than Angry Birds.

There are literally a few hundred online courses that teach you how to create iPhone apps. These are done using tutorials that breakdown the entire "programming lingo" down to plain English so that you fully understand the process. If this still seems too time consuming you can find software that is downloadable. These have programs that you can use or modify slightly to create an iPhone app that is unique.

In addition to these options there are websites and other platforms that even offer templates that help you to create iPhone apps. The first thing you need to do is to familiarize yourself with the developing tools and once you get a handle on this you can go just about anywhere with your programming. Making apps calls for the use of a vivid imagination. It is a process that will take your being able to see the different layers that need to be developed to make a game fun and exciting or to visualize what the end results of function should be.

Now that you know there is a way for you to create iPhone apps there is one thing you have to do before you begin this journey. In a word "RESEARCH", this may be the single most important part of the app creation. You want to look for a category of apps that has a great demand but very few competitors. The more competition there is for a category the harder it will be for you to sell your app. If you do go for one with a lot of players you have to come up with the most unique and useful idea and be the first to get it out there. Making apps can be done, even with no experience check out these links for more information.

Anissa Williams

Galaxy Tab 2 And IPad Comparison

Samsung and Apple are into court battles because of the claims of the latter copying the designs of the former. The Galaxy Tabs are one of those products that said to have been copied from the iPad. But amidst the controversies, it had enjoyed some success behind Apple. It provided some alternative for those who either have no money to spend on shinier devices or just hate all products by Steve Jobs.
Users are expecting another product when the Galaxy Tabs 2 was announced. This was during the time when the rumors of the release of the iPad 3. But when the news about the specifications of the new tablets by Samsung came out, there was nothing to be impressed about.
All the hardware remained the same as the original. There is the dual-core NVIDIA Tegra 2 which is the same with the one on the Galaxy Tab 7.0 Plus. This processor is not an improvement over the original's Exynos processor. Actually, the Exynos is faster at is clocked at 1.2 GHz while the Tegra 2 is clocked at only 1 GHz.
The screen resolution is also the same which is depressing for Galaxy Tab loyalists. This is probably because of the news that the iPad 3 will have retina display and their favorite tablet has no improvements on this area. The 10-inch version will remain at 800 by 1280 pixels and the seven-inch version will stay at 600 by 1024 pixels.
While tablets are now transitioning to 4G LTE connectivity, the Galaxy Tab 2 remains at 3G. Just like the original, you have a choice between 3G and Wi-Fi and Wi-Fi only models. The speeds are the same as original: 21 MB/s for download and 5.76 MB/s for upload.
The only improvement on the Galaxy Tab 2 is the interface as it now sports the latest Android version, Ice Cream Sandwich. This version is the best looking version of Google's mobile OS besides offering a slew of new features. Ice Cream Sandwich is Android's answer to the simple elegance of Apples iOS 5.
With all of these, it seems like the Galaxy Tab 2 is just the original upgraded to the latest Android OS. ICS is good but we would have expected something better in terms of hardware from a company such as Samsung like what ASUS did with their Transformer Pad. There could have been added functions such as NFC or, as mentioned, support for 4G LTE. No prices have been released yet for these devices. But there are rumors that they will be sold at a lesser price than the original. If this is true then the Tabs are worth a look in terms of practicality. But performance wise, the new tablets by Samsung are depressing.

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