To simulate the event, a technique called multibody simulation is used (ADAMS is a software dedicated to that). Basically it's a physics simulator to perform analyses in time-domain. That's jargon for "it's a sandbox for engineers".
Because we cannot know in advance what the exact conditions for the landing will be, engineers resort to "Monte Carlo simulation". That's jargon for "we are running thousands of calculations with changes on the initial assumptions to cover all cases".
(Thread) Shall we talk a bit about #MarsPerseverance 's EDL sequence? Let's start with the parachute. The design is called a disk-gap-band parachute. Picture below is from Tutt, Lowry, 2019. As you can see, there is a disk of fabric, a gap and a band of fabric. Hence the name!
It's a design already proven on the Viking Mars probes. However, there have been some changes to the original design.
To clarify, a "gore" is a segment of fabric that runs from the center to the rim, shaped somewhat like this: