HANDWRITING RECOGNITION SOFTWARE
This software embedded in the microprocessor of the pen is used to recognize handwriting of the user. Pen works in conjunction with a regular PC on to which users install special handwriting recognition software. The handwriting recognition software translates movements in to text on screen.
Handwriting recognition software constitutes two major phases:
1. Handwriting transcription
2. Handwriting recognition
In this phase, the recorded acceleration signals are then transcripted to itâ„¢s original form. Here this aspect is solved using Ëœsimpleâ„¢ double integration method in order to retrace the pen tip movement on paper.
In order for this principle to work properly, we have to solve two main problems:
Firstly, we have to know penâ„¢s spatial orientation in order to withdraw the earth gravity component to the measured accelerations.
Secondly, we have to succeed in the double integration, which is to solve all the derivation problems due to this method.
The algorithm used for handwriting transcription is the following:
We can see two pictures:
Fig (1) represents the acceleration signals recorded while one is writing a small capital B.
Fig (2) is the transcription result obtained with algorithm presented
The second huge aspect is the characters and signatures recognition. The hardware (accelerometers plus contact detector) embedded in the pen has proved a really efficient combination for this application.
The same method is used to recognize the characters written by a single user and to find whose signature is the one that has just been done.
We use a simple Euclidian distance as the comparison process, and of course the decision process is the smaller distance found.
The first step -1- consists in creating the reference database for the characters as for the signatures. For this a mean signal is computed for each recorded symbol.
The second step is the recognition process
For the creation of database, each symbol was reproduced several times and a mean normalized symbol was computed.
For recognition process, the unknown symbol is first normalized, the distance between this symbol and the entire database symbol is computed. Then the unknown symbol is recognized as the one with the lowest distance.
The results shown in this part are for signature recognition but they are similar as the one obtained for character recognition
The corpus used for signatures was made by 10 different signatures from 10 different people. They made 10 attempts for the database, and 5 others for the test base.
In Fig 1, we can see the accelerometers signals recorded during Yaniâ„¢s signing process. Fig 2 shows the distances computed between the unknown signature and the oneâ„¢s in the database. Yaniâ„¢s signature was the last one learnt(number 10)and we clearly see in Fig 9 that his signature was well recognized.
In Fig 2, the X-axis represents the different symbols of the database, and the Y-axis is the distance from the unknown new symbol to the oneâ„¢s from the database.
Display scrolls by tilting screen
By tilting the pen, user can choose applications and scroll through with out using scroll buttons. Below is an image of SmartQuill tilting Screen designed by Lyndsay Williams for BT Labs in 1997. The pen would align text if it was held in left or right hand so the text was the correct way up for left or right handed people. This was done by using Micro Electromechanical Systems (MEMS) tilt sensors to measure tilt angle to earth. The SmartQuill microcontroller read the angle and then mapped the large screen display onto the small 4 line display. SmartQuill could also scroll through pages of display by tilting it in the hand and power off if no hand movement was detected or pen was flat on a desk. The demonstration unit below shows display inverting as SmartQuill was inverted in the hand. The choice of words was limited to what characters the LCD display driver could show while upside down (left hand picture) â€œ only 14 of the 26 letters of the alphabet were usable. These 14 characters were then processed by anagram software to produce 900 words that used these characters. The shopping list below was produced from this limited dictionary to demonstrate the text inversion
WITH OTHER DEVICES
Earlier SmartQuill models developed by BT laboratories communicated with the PC via a radio transmitter, but the current prototype hooks up to a PC via a cable and electronic docking station called an inkwell. .The data stored in the memory is uploaded to the personal computer when it is placed in to a docking station. An electronic docking station is a small cabinet to which a laptop or notebook computer can be attached for use as a desktop computer, usually have a connector for externally connected devices, such as hard drives or scanners and ports that can be linked to components such as keyboard, monitor and printer. It can also be connected to printer, modem or mobile phones to send data electronically.
The output accelerometer signals from the pen are digitized with a National Instrument capture card with a frequency Fe of 1000Hz and a low pass filter at Fc=1/3*Fe .
Future models could receive e-mails and pager messages via a wireless messaging system .This enables two-way wireless communication with other computing devices .
SmartQuill has 4MB EEPROM memory. At a time, up to 10 pages of notes can be stored locally on the pen. The data is stored in the memory on the pen until it is uploaded to the personal computer. SmartQuill works by measuring the penâ„¢s movements and matching them to the movements that produce letters and words programmed into its memory. Itâ„¢s similar to the way a microphone detects sound.
SmartQuill is powered by AAA battery. It will run for about 25hrs on a single AAA battery. The pen exhibits automatic power on/off system. The pen will power down after a period of no movement. So it supports automatic on/off system.
SmartQuill isnâ„¢t all space-age. It contains an ink cartridge so that users can see what they write on paper .Hence a simple application of SmartQuill is that it write notes on paper. This information recorded in the pen is then downloaded to PC.
The information stored in the pen can be input to other devices such as mobile phones, printers, modems, desktop computers etc for different applications.
It also provides handheld computer applications such as digital diary, contacts, calculators etc.
It is used for receiving pager and e-mail messages. This is possible through recent technology involved in SmartQuill, the wireless messaging system which allows two way communication between devices .
SmartQuill synchronizes files, e-mails and messages to PC.
SmartQuill can be used for voice record and supports speech recognition. Voice record is made possible through ADPCM speech compression .
SmartQuill also allows third party to add on applications
One of the major asset is that SmartQuill does not need a screen to work. This is possible through revolutionary Spatial Sensing system which uses semiconductor accelerometers. Accelerometers senses pen/hand movement instead of shapes.
SmartQuill provides intuitive user interface.
Security â€œ Security is another important feature. It is made possible through two facilities:
It enables handwriting recognition .User can train the pen to recognize a particular handwriting style. The symbols regularly used by user gets stored in the memory, by frequent use of the pen. Hence the pen accepts only the ownerâ„¢s handwriting and rejects intruders handwriting.
It enables signature verification. Hence Passwords could be entered in the form of signatures .
The SmartQuill is also a 3D-mouse, when twisted in air in a certain way it enables scrolling of the screen. It also automatically detects left or right handed use.
Small screen size requires less battery power .
No movement of the pen causes auto power down
SmartQuill is all mobile, smaller in size and enables one-handed use.
SmartQuill will be brought to the market by the end of 2004.The estimated cost of this futuristic pen is around $200.SmartQuill supports two factors : small size and convenient use. The future of SmartQuill ensures all computation power the user needs right inside the pen. Reducing the size of handheld computers can only be taken so far before they become unusable. Keyboards become so tiny you require needle-like fingers to operate them and screens that need constant cursor controls to read simple text. The introduction of SmartQuill is the best solution for this problem.