Thursday, December 22, 2005

Text Entry Innovations – Tap, Type, Graph, Predict, or Say It

Making text entry easier and more efficient has obvious benefits to the mobile computing space. As Virtual Instrumentation moves from workstation to desktop stations to handheld devices, text entry becomes an important enabling technology.

Palm gave us the graffiti editor and the modern cell phone brought us Standard Ambiguous Code (SAC) which places “ABC” on the first key, “DEF” on the second key and so forth. The user makes multiple taps on a key (called multitap) to choose a letter. One tap on number 1 key brings up the letter “A”, two taps the letter “B”, and three taps the letter “C”.

Text entry systems reuse keys to create more input letters within a constrained space. Some systems use linguistic techniques to predict the word the user is entering and perhaps the one that will come next. Other systems create dictionaries (either user created or system created) to provide the words for prediction. Linguistic rules may not keep up with the ever changing language while dictionary systems require more memory to hold the required words.

Motorola’s iTap improves on this by allowing the user to hit the key once for each letter in the word to be entered and then using a dictionary to make out the correct word since each tap can represent one of three letters. T9 offers a demo on how multitap works and also provides a dictionary with updates to our ever growing language.

IBM’s “Alphaworks,” their nomenclature for emerging technologies, has created Shorthand-Aided Rapid Keyboarding. It uses “Sokgraphs” (Shorthand On Keyboard Graphs) which are letter tracings using a pen on a keyboard layout for either QWERTY or ATOMIK, that can be stored and used later. It takes some getting used to but it’s a natural progression from graffiti used by the Palm to outline each letter in a word you want to enter. To see it in action, check out the video clip here. Based on usage, the system can learn and start to predict words based on previously built words. IBM brands its stylus-based technology for text entry as Shapewriter, and offers a demo download here.

Eatoni makes predictive text entry systems for handheld devices. At first I thought the inventor was named Eatoni. Then I found their FAQ which indicates the name came from the six most common letters in the English language –E-a-t-0-n-i. Eatoni’s technology EQx stands for "Eatoni Qwerty x-column" which works in either 3 or 6 columns. EQx merges a QWERTY keyboard with a telephone keypad. Eatoni claims to extend the work of Scholes who invented the QWERTY keyboard by designing a keypad that predicts the word the user wants and avoids collisions in the keypad entry. Demos are available here.

Zi Corporation’s eZiTap uses a modified form of the multitap technique to perform word completion and prediction.

Senseboard is a Swedish company that offers a virtual keypad for text entry into mobile devices. Consisting of two hand-worn devices and a scanner, it detects the motions of the fingers as they type out a word on any surface. This eliminates the scrunching of the fingers trying to type on a tiny surface of keys.
Speech recognition seems an obvious technology and has been around for some time but has encountered numerous problems. In this review of a speech by Dr Gong Yi Fan the author divides the problem into three categories: performance, noise, and adaptiveness. In the area of performance, mobile devices are power constrained. Speech recognition can be processor intensive which can be power intensive. Background noise can also compromise speech recognitions’ capabilities. Finally, the speaker can also change his voice characteristics including pitch, volume, etc, challenging speech recognition’s ability to accurately translate the spoken word into textual entry.
If you are working with text entry systems, I would like to hear from you. You can reach me at

Best regards,
Hall T. Martin

Friday, December 16, 2005

Nanosatellites – Coming to a Classroom Near You

Nanosatellites are soccer-ball sized devices that NASA launches into space. Initially targeted for studying the earth and the sun, nanosatellites are finding numerous missions such as orbital communication networks, and remote sensing. Nanosatellites are fueled by butane (similar to what lights a cigarette lighter) and are generally made for less than $100K.

Using commercial off-the-shelf technology numerous universities and organizations are now developing their own nano or micro-satellites. The IAF – International Aeronautical Federation plans to launch 50 nanosatellites on the 50th anniversary of Sputnik in 2007. Cornell is developing a network of nanosatellites that can perform end-to-end inspection which could be used on such structures as the International Space Lab and could have been used to inspect the ill-fated Columbia flight.

The University of Texas is developing PORTIS (Proximity Operations Rapid Turnout Inspector Satellite) which is two satellites that will remain within 10 kilometers of each other as they orbit the earth taking photographs. The purpose of the launch is to perfect techniques for controlling multiple satellites and working in concert. To control the rotational position of the satellite, they used QBX, a small 4x4cm data acquisition system running embedded LabVIEW.

The number of nanosatellites being launched by Universities is growing to such a point that it is becoming a driver in the world of satellites. In the 1990s, the LEO satellites for communications such as the Iridium project drove the satellite market. Today, nanosatellites are becoming a presence to reckon with. In this article satellite market analysts review the launches throughout the 1990s and go on to predict the growth of the market. The Teal Group tracks current satellite payload launches and predicts the type and number of future launches. They predict over 1200 satellites will be launched between 2004 and 2013 and that 3% will be university developed nanosatellites.
There are some companies involved in nanosatellite work. AeroAstro provides transponders and other communication tools for nanosatellites.

Virtual Instrumentation provides test support , ground-based data collection, system enhancement, and more.

If you are working with nanosatellites, I would like to hear from you. You can reach me at

Best regards,
Hall T. Martin

Friday, December 09, 2005

Nanotechnology—Make Sensors Smaller and Cheaper

Nanotechnology pushes the boundary not only on the electromechanical side of the device but also on the sensing side. Chemical sensors using organic semiconductors and inkjet printing technology are now a reality. University of California, Berkeley’s Subramanian claims to make these sensors for $0.30 each. Borrowing the concept from how the human nose detects smells, Subramanian uses an array of sensors to detect a variety of chemicals.
Using inkjet printing technology appears to be a common theme. Here’s a paper from 2003 describing the technique.

Sensors array have been used in an Electronic Nose application in which sensor arrays detect volatile chemical elements (those that tantalize the human senses). A sensor array – each one tuned to a slightly different element more closely approximates how one may taste or smell. Chromatography and Mass Spec techniques try to resolve each element but this is insufficient since it doesn’t take into account the interaction with the human senses. The sensor array can change its reading based on the chemical interactions it receives. Also, a series of sensors can provide a more accurate portrait of a target chemical especially when coupled with pattern matching software. Applications range from food, beverage testing to gas vapor analysis, to medical.

NASA Tech Briefs describe an optical sensor array modeled on a moth’s eye (which reflects no light) that uses nanometer size pillars shorter than the wavelength of light. By varying the size of the pillars one can build a filter/sensor spectrometer unit with no moving parts.

Researchers at the University of Tokyo use arrays of organic sensors to create a “skin-like” material that can sense pressure. One application is to spread this material on the floor so if someone falls, the sensors in the skin can detect the presence and the condition of the subject. It can also be applied to robotics applications in non-trivial applications such as a robot picking up an egg. The sensors can detect the amount of the pressure being applied and the objects’ response to it.

Startups are also working in this space.
Concentris a Swiss-based company uses cantilever arrays to detect chemicals in their instruments.

If you are working with sensor arrays, I would like to hear from you. You can reach me at

Best regards,
Hall T. Martin

Friday, December 02, 2005

From MEMS to NEMS – the Ever Shrinking World

MEMs stands for Micro-Electro-Mechanical systems and represents the integration of mechanical elements, sensors, actuators, and electrical elements in a single device, making possible complete systems-on-a-chip and augmenting microelectronic capabilities with microsensor and microactuator capabilities. NEMs is the nanoversion of the same thing.

MEMs are built on the micrometer level and use semiconductor techniques such as 3D lithography to develop its features. The large surface area to volume ratio make surface effects such as electrostatics dominant compared to volume effects such as inertia or thermal mass. The Wikipedia definition provides more details.

An electromechanical system consists of two elements – a mechanical element and transducers. These have been existence for over 200 years. Mechanical devices measure vibration in response to an applied force. There are several kinds of devices including cantilevers, double-clamped beams, and torsion balance. Transducers convert mechanical energy into electrical or optical signals. For more details on electromechanical systems, check out this article.

Nanomechanical devices take this technique to an even smaller scale measuring even tinier vibrations reaching into the microwave arena with great sensitivity.

The Nano 50 Awards were recently announced. The list of winners indicates a technology emphasis on alternative energy and semiconductor techniques and a product emphasis on new materials.

Recent trends include improved sensitivity of sensors, advanced development of scanning probe microscopy and better high-frequency filters and switches in signal processing circuits.

UCLA recently created the Nano-valve which can hold and release molecules at will. Recent advances in carbon nanotubes make nano-switches possible. Applying electrical input deforms the nanotube in a predictable manner. This deformation coupled with careful positioning of the device can create a nano-switch. A more detailed explanation can be found here.

Virtual Instrumentation brings tools to the task of characterizing nanoparticles. Since quantum mechanical rules apply at the nanoscale, particles bond differently and thus must be characterized. For particles on the nanoscale, scanning tunneling microscopes and atomic force microscopes must be used. Nanomanipulators can be used to bring the electrical signal from the nanolevel out to a point that instrumentation can measure the current. Here’s an interesting nanohandling application using haptic interfaces.

If you are working with MEMs or NEMs technologies, I would like to hear from you.

Best regards,
Hall T. Martin