TOKYO – Hitachi’s robots on wheels avoid obstacles, respond to simple voice commands and read the weather forecast.

But they are very much a work in progress. Reporters invited to a demonstration were warned not to touch the two prototypes for safety’s sake. They also were asked not to use a camera flash at certain angles or to cross a white line on the floor.

The 150-pound, 51-inch-tall robots, nicknamed Pal and Chum, are equipped with digital cameras and radar sensors, allowing them to avoid obstacles with a reaction time of one-tenth of a second.

They don’t have legs but zip around on two wheels at the speed of a slow jog. They appear a bit wobbly but manage to balance themselves and won’t fall, even if nudged gently.

One showed it can raise its arm upon command. It also swiveled in a circle, gave directions to the bathroom and read the weather forecast.

“My name is Pal, which means ‘friend,’ “the mouthless robot said in Japanese in a soft, electronic voice.

Internet-based phones may not handle 911 calls: Joyce John was upstairs at her Houston home when suddenly she heard gunshots and her parents screaming. Her mother, faced with two armed robbers, yelled for the 17-year-old to dial 911.

But she couldn’t complete the call. John’s parents were both bleeding from gunshot wounds by the time she realized the family’s Internet-based phone wasn’t activated for 911. (They were later rushed to a hospital and survived).

While the federal government considers rules to extend 911 requirements to so-called Voice over Internet Protocol, or VoIP, phones, emergency network operators are warning potential customers about the services’ shortcomings.

They have set up a Web site at http://911voip.org.

“The onset of an emergency, especially a life-threatening emergency, is not a good time to find out whether or not your service provider gives you access to 911,” said John Melcher, executive director of the Greater Harris County 911 Emergency Network, which serves the Houston area.

Rick Jones of the nonprofit National Emergency Number Association says 911 availability varies widely, and some providers even offer different functionality in different markets.

Some VOIP services offer the same enhanced 911 capabilities available on conventional phones; in such cases, emergency dispatchers get crucial information such as the callers’ phone number and address, in case they cannot speak. Others offer only basic 911 services – without location. Some can’t hook up directly with 911 and instead call a ten-digit administrative police line that isn’t always equipped for emergencies.

The Johns’ provider offers a ten-digit option in that area, but they didn’t know they had to activate the service first, 911 officials say.

Text messaging isn’t for everyone: A quarter of American adults who have cell phones have used the devices’ text-messaging features within the past month, a new study finds.

Usage correlates with age: 63 percent of cell phone users ages 18-27 have used text messaging compared with 31 percent for ages 28-39 and 7 percent for those over 60.

The Pew Internet and American Life Project also found that 28 percent of people who used text messaging have received unsolicited commercial messages that way.

Text messaging allows cell phone users to receive and send short messages to other cell phone users or e-mail recipients. Services also are available to receive news alerts and other information through text messaging.

Also known as SMS, for Short Message Service, “texting” is highly popular in Europe and Asia but only starting to catch on in the United States.

Author seeks input: Stanford law professor Lawrence Lessig is turning to his readers to help him update his 1999 book “Code and Other Laws of Cyberspace.”

Readers can contribute by visiting a wiki, a forum in which anyone may add, edit and even delete information already submitted by others.

The update, to reflect changes in law and technology since the original publication, is scheduled for publication later this year, according to JotSpot, the company providing the wiki technology.

Lessig isn’t the first author to seek community input.

Dan Gillmor, former tech columnist for The Mercury News, circulated drafts of “We the Media” online and sought feedback before publishing the book last year.

Herald news services