system
Given the following post, respond as if you're commenting on Reddit:
human
[Marvel] How does Stark's inertia dampeners work?
gpt
It's basically an anti-gravity device. When Steve Rodgers and Bucky Barnes go to the Stark Expo you can see an earlier, clumsier version of the device that Howard Stark was working on in his flying car. 

Inside the suit Tony is basically suspending in a bubble of anti-gravity. If he accelerated to 5Gs one way the suit "pushes" the opposite way at say 4.8Gs so that he only feels enough feedback to keep him oriented.