Oct 062011

Straight from the start I should mention that I am a android fan boy so I may lean to the android side a bit.

Firstly let me introduce my phone, the Sharp 005 SH. If you haven’t heard of it then don’t worry its only sold in Japan. The phone was released at the beginning of 2011.

Heres the features:

  • 1 GHz Cpu
  • 512 Mb Ram
  • Android 2.2 2.3(updated)
  • 3-D display(same tech. as the Nintendo 3ds, Sharp makes the screens for Nintendo so go figure)
  • One-seg digital tv
  • HDMI port
  • Irda (infrared data transfer)
  • Felica-Keitai based Near Field Communication (Works as a digital wallet in Japan)
  • Slide out QWERTY keyboard
  • 8 MegaPixel camera
  • Support for SDXC(32Gig+ SD cards)
  • Bluetooth, Wi-fi, gps, digital compass, the usual goodies

Now for the new iPhone 4S

  • 1 GHz Dual core CPU
  • 1024 Mb Ram
  • iOS 5
  • 8 MegaPixel Camera
  • Frontal camera
  • 64 Gb internal memory
  • Bluetooth, Wi-fi, gps, digital compass, the usual goodies

From my point of view there are three big differences between these phones, first the iPhone is faster with double the CPU and RAM but then again my phone is 10 months older so I would expect as much.

Secondly the new iPhone has a frontal camera, that surely would be nice to have for apps like Skype and the hangouts in Google+.

Thirdly , and this is why I think my phone is still batter, the iPhone is lacking several features such as the 3D display, One-Seg tv, HDMI, Felica-Keitai, QWERTY keyboard and Irda. To be fair half of these features aren’t so useful anyway. For instance, I never use Felica-Keitai although one day when I feel like going through all the hassles of the registration process it may be handy to buy drinks from vending machines and get past toll gates at train stations by simply swiping my phone. Irda is somewhat useful in Japan since the majority use it to exchange contact details. The 3D display tires your eyes and its only usable in applications that enable it. On the other hand the 3D screen also provides the “veil view” feature which is indispensable in crowded areas, when I feel like someone next to me is looking on my screen I simply hit a hardware button and voila! I can see the screen but  anyone who looks at it from an angle such as the people next to me see a weird scrambled pattern. Then when I want a clear&easy to view screen I simply disable veil view mode and It becomes a normal screen again. Other features like QWERTY keyboard and one-seg TV are very handy indeed. HDMI is also nice to have because sometimes you want to watch those recorded one-seg programs on a bigger screen or watch some youtube videos through your TV and thanks to the two way communication ability of HDMI I can control the playback process through my TV’s remote control without even touching my phone.

Then there are some fundamental issues I have with iPhone devices.

  • Can’t swap batteries
  • Can’t use SD cards
  • OS not open source

I prefer options and hack-ability. On a side note, open source  represents the minimum bar for software. If your proprietary software is worse than the opensource alternative then you lost. Thats the great thing about open source, its lifting the standard for software & forcing companies to work harder or base their product of the open source alternative while adding value. So if iOS is roughly on the same level as the new android version then I think apple is in hot water.

To round this post up, other than the increased horsepower and frontal camera I can’t see what makes the new iPhone  better than my 10 month old phone. It seems like a average phone, inferior in many ways to its contemporaries such as Samsung’s Galaxy SII and the Google Nexus Prime. Perhaps Apples new strategy(by no means a bad one) is budget smart-phones.

Lastly perhaps Apple should open source iOS ?

 Posted by at 8:05 am
Mar 022011

Finally my Masters research is complete. Here is a experiment video highlighting my work

embedded by Embedded Video

This method takes joint torques(generated by position controller) and converts them into the force domain so that they can be limited(to prevent tipping, twisting, sliding, etc) and finally realized via force control.

So essentially the position controller becomes a reference force generator.

The advantages of this method are:

  1. No ZMP trajectory is needed: ZMP moves freely to realize the desired motion but the forces at the foot are constrained to prevent tipping(ZMP going to edge of support)
  2. Prevent sliding&twisting of the foot and prevent excessive GRF’s after jumping: Limit all 6-axes of the force wrench to prevent unstable/undesirable situations.
  3. Improved robustness: It is proved that this method has the same positioning performance as pure position control(as long as force limiting is not needed). Any position controller can be used since the inputs are the desired joint torques. Therefore motion response depends purely on the position controller used.
  4. Independent joint control: The joints can be moved separately as long as the degrees of freedom dont exceed 6 and the manipulator is not in a singular position.

Here is a block diagram of the method:

Please read my  Masters research page for more details.

Now that the intuitiveness of position control has been combined with the versatility of force control. I look forward to advancing the field of robotics in my PhD 🙂

 Posted by at 6:49 pm