Wednesday, May 15, 2013

Surgical Robots

At the Leprecon 39 Science Fiction Convention I attended a talk by Dr. Bruce Davis, a general/trauma surgeon in the Phoenix area.

Dr. Davis has done many laparoscopic surgeries using the da Vinci robot.  Instead of opening up a patient's belly, a small incision is made. A pair of robotic arms as well as a binocular pair of cameras are inserted through a small opening.

Davis reports that the two cameras give good depth perception. The telepresence is so immersive he often forgets he's not physically present inside the patient's body. He finds himself trying to turn his head to look about the cavity. Davis expects the robots will soon have motion capture for the head and neck so the camera motion will mimic the motion of the surgeon's actual eyes.

The arms are operated by motion capture. Robotic wrists mimic the motion of the surgeon's wrists. Instead of a thumb and four fingers, the robotic hand looks more like a crab's pinchers. The surgeon moves these pinchers with his thumb and index finger. Still, a lot can be accomplished with this simple hand.

The cameras give up to 10X magnification. When higher magnification is invoked, the motion of the robotic hands become more minute -- in effect shrinking the surgeon's avatar. We saw a video where a grape seemed like a large watermelon. The surgeon easily cut and peeled back a section of the grape's skin.

The robotic hands lack a sense of touch. Davis says the robot's designers are trying to figure out how to do haptic feedback but it's a challenging problem.

The da Vinci robot Davis uses costs 1.2 million dollars. I noted design and development is a large expense for early technologies. As more robots are made, design cost is amortized over more units and unit price can fall. Davis replied that this is happening to some extent. But da Vinci is the sole vendor in his field of robotic surgery and so has less incentive to drop their price.

I asked Dr. Davis if he foresaw uses of this technology outside of surgery. For example snaking robotic arms and eyes to a problem inside a utility line. This might avoid busting up a busy intersection with jack hammers and backhoes. Davis replied that this sort of application is likely and will probably lead to cheaper robots. Liability is a big expense in surgery. For example, a titanium screw breaking in a hip replacement can result in a major law suit. The same titanium screws that cost air lines $4.00 apiece are sold to surgeons at $400 apiece. Not having a heavy insurance burden, robots for plumbers and electricians can be less expensive and more common place than surgical robots.

I asked Davis if he thought telerobots could be used to build infrastructure on the moon or on an asteroid parked in lunar orbit. He said due to the 3 second light lag, motions would have to be very deliberate. But he thought it was doable. He mentioned there is a.i. being developed that mitigates slow reaction time caused by latency. For example, Big Dog's balance or Google Cars collision avoidance.

In Puppets, Telerobots and James Cameron, I opined that telerobots will be the game changer that enables use of space resources. I wrote that there are many uses right here on earth that are advancing telerobotic technology. So Davis' presentation was encouraging to me. Dr. Davis is also a science fiction writer.

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