Video chatting with other people can provide a greater sense of immediacy than an IM or even a phone exchange, but it's still not like being in the same room. Researchers at Osaka University are trying to help cross that gap, however, and their tool of choice is a robot arm that shakes hands. The goal is to provide a greater sense of "presence" when interacting with somebody through a monitor or screen. When conducting tests for the device, the researchers discovered that the three most important elements needed to create the illusion of touching a person's hand were the texture, temperature, and the grip force itself. For texture, they utilized a combination of silicone rubber and sponge, providing the feel of a human hand with skeletal infrastructure, with a film heater providing the warmth. Interestingly, people that used the device carried certain preconceived notions with them — namely, that a robot hand would be cool to the touch. The researchers actually had to heat the hand up hotter than the outside of a normal human hand — up to 98.6 degrees Fahrenheit from their starting temperature of 89.6 degrees — for it to feel correct. The researchers are planning to apply the technology to tele-presence products, and are already working on a version with pressure sensors in the hand for a more interactive grip.