Surgical-assist devices let doctors remotely perform medical procedures with small tools and great precision. But the devices, which some mistakenly call robots, have no sense of touch. That means pull too hard on a stitch, and the thread breaks. Researchers at Johns Hopkins University are trying to change that by adding haptic feedback or feel to surgical tools.

A team lead by associate professor of mechanical engineering Allison Okamura is investigating several techniques. “One uses force sensors to tell of loads applied during surgery. Another approach uses software to generate haptic feedback to the operator. Even visual cues, such as a red dot over the instruments in the video display, can tell doctors they are applying too much force,” says Okamura.

The team is working with Intuitive Surgical Inc., maker of the da Vinci Surgical System. “Surgeons would like to feel what's happening during operations. Ordinarily, they can feel a pop when a needle pokes through tissue and feel for calcification. Touching helps them know where they are within the body.”