Robotic surgery is essentially an outgrowth of laparoscopy. Laparoscopy can be difficult because the instruments need to be long and straight to be inserted through the skin. It can thus be difficult to reach some areas and to manipulate the tissues appropriately (imagine trying to sew with chopsticks). Robotic surgery attempts to overcome these limitations. Miniaturized, motorized robotic arms are inserted into the body in the same way as the traditional laparoscopic instruments.
The surgeon who is sitting across the room controls the arms. A camera is inserted in the same way as laparoscopy to provide visualization to the surgeon. The added flexibility of the instruments significantly decreases the difficulty of the procedures and therefore the amount of time it takes.
Robotic surgery is commonly performed for prostate cancer surgery, and many skilled robotic surgeons are now performing radical cystectomies robotically. Some surgeons will remove the bladder robotically but perform the urinary diversion through a small abdominal incision. The advantages of robotic surgery are smaller incisions and less postoperative pain. The procedure has not been proven to be better than open radical cystectomy in terms of cure rates and potency rates.