In Mark Waid's comic book series "The Indestructible Hulk," Dr. Bruce Banner's new motto is "Hulk destroys, Banner Builds." He claims that he can better control the beast within him, and urges SHIELD Director Maria Hill to think of him as a cannon rather than a bomb. As much as Maria Hill would like to believe that Banner can control his transformations, and retain some conscious control over the Hulk, history is not on his side. Still, he's offered to take the Mad Thinker down for her. So, when he's not looking, she grabs a piece of wood, and takes the direct method of activating the Hulk.
Like SHIELD, Dr. Bruce Banner learned of the Mad Thinker's secret WMD manufacturing plant. Once he transforms, the Hulk charges off toward the facility. There he finds the Mad Thinker manning one of the large battle suits he developed based on Ultron's technology.
The Mad Thinker believes he has the measure of Hulk. Like so many before him, he learns it's all too easy to underestimate the Hulk's ability to absorb punishment.
With all the weapons and manpower operating at the facility, awaiting the "secret" SHIELD raid the Mad Thinker anticipated, Maria Hill is glad the Hulk was with her on this mission.
After the raid, Maria Hill decides to grant Dr. Bruce Banner a trial period, begins hiring assistants for his laboratory, and sends him out on a few more operations. Given his new methods of controlling himself, she begins to see their relationship as doable. Still, knowing how volatile and dangerous the Hulk can be, she puts a few checks in place to make sure he's really keeping up his end of the bargain.
One is ROB, otherwise known as a Recording Observation Bot. ROB will hover around Banner, keeping him (and the Hulk) under constant scrutiny. Maybe Banner can change. Maybe he can gain control over his transformations. Maybe the Hulk can even learn to take instruction, and stay focused during missions, instead of just letting go and smashing everything in sight.
Dr. Banner may understand the logic behind Maria Hill's decision. That doesn't mean that he likes the constant surveillance.
For more on Dr. Bruce Banner's attempts to be a force for good while working under Director Maria Hill, read The Indestructible Hulk Volume 1: Agent of SHIELD by Mark Waid. Prepare yourself for a confrontation with Iron Man, a mission into an active volcano, an undersea battle between two aquatic nations, and, oh yeah, the return of ROB.
(Way to hang in there, ROB!)