# Non-equilibrium pulling - force ramp **URL:** \ **Category:** User discussions\ **Created:** [March 6, 2024, 2:26pm UTC](https://gromacs.bioexcel.eu/t/non-equilibrium-pulling-force-ramp/8536 "2024-03-06T14:26:33Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![gfg](https://avatars.discourse-cdn.com/v4/letter/g/9fc348/32.png) [@gfg](https://gromacs.bioexcel.eu/u/gfg)\ **Post date:** [March 6, 2024, 2:26pm UTC](https://gromacs.bioexcel.eu/t/non-equilibrium-pulling-force-ramp/8536/1 "2024-03-06T14:26:34Z")
GROMACS version: 2019 GROMACS modification: Yes/No I’m trying to perform a non-equilibrium pull of a protein construct by constantly increasing force in the form of a force ramp. For reference, please refer to the attachment ([https://doi.org/10.1016/j.sbi.2019.12.015](https://doi.org/10.1016/j.sbi.2019.12.015)). What changes should I make to the production .mdp file? Thanks a lot! ![force_ramp](https://europe1.discourse-cdn.com/flex017/uploads/bioexcel1/original/2X/e/e66c3892b1a82debf09aebc70519d402f75ce27a.png) ---
**Author:** ![alevilla](https://dub1.discourse-cdn.com/flex017/user_avatar/gromacs.bioexcel.eu/alevilla/32/439_2.png) [@alevilla](https://gromacs.bioexcel.eu/u/alevilla)\ **Post date:** [March 8, 2024, 5:07pm UTC](https://gromacs.bioexcel.eu/t/non-equilibrium-pulling-force-ramp/8536/2 "2024-03-08T17:07:58Z")
Hi, my first suggestion will be to look at the mdp option for the pull code if there is something that fits for your case [https://manual.gromacs.org/current/user-guide/mdp-options.html#com-pulling](https://manual.gromacs.org/current/user-guide/mdp-options.html#com-pulling) For an overview of the method you can have a look at [https://manual.gromacs.org/current/reference-manual/special/pulling.html](https://manual.gromacs.org/current/reference-manual/special/pulling.html) Then you could test if you got the expected results. Kind regards \Alessandra