# Relative positioning of jaws on newton gripper **URL:** \ **Category:** Newton Gripper\ **Created:** [April 17, 2019, 4:40pm UTC](https://discuss.bluerobotics.com/t/relative-positioning-of-jaws-on-newton-gripper/4864 "2019-04-17T16:40:46Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![etienne](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/etienne/32/1942_2.png) [@etienne](https://discuss.bluerobotics.com/u/etienne)\ **Post date:** [April 17, 2019, 4:40pm UTC](https://discuss.bluerobotics.com/t/relative-positioning-of-jaws-on-newton-gripper/4864/1 "2019-04-17T16:40:47Z")
Hi guys, Finally got around to installing the newton gripper. Works well but the jaws either opens completely or shuts completely. Is there a way to partially open the jaws? Cheers, E. ---
**Author:** ![jwalser](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/jwalser/32/2234_2.png) [@jwalser](https://discuss.bluerobotics.com/u/jwalser)\ **Post date:** [April 17, 2019, 5:20pm UTC](https://discuss.bluerobotics.com/t/relative-positioning-of-jaws-on-newton-gripper/4864/2 "2019-04-17T17:20:03Z")
@etienne try the \_max\__ **momentary** _ functions on the joystick buttons ---
**Author:** ![etienne](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/etienne/32/1942_2.png) [@etienne](https://discuss.bluerobotics.com/u/etienne)\ **Post date:** [April 18, 2019, 2:32am UTC](https://discuss.bluerobotics.com/t/relative-positioning-of-jaws-on-newton-gripper/4864/3 "2019-04-18T02:32:25Z")
Hi Jacob, I tried that and all other available options. Same results either fully open or fully closed. Cheers E ---
**Author:** ![jwalser](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/jwalser/32/2234_2.png) [@jwalser](https://discuss.bluerobotics.com/u/jwalser)\ **Post date:** [April 18, 2019, 2:35am UTC](https://discuss.bluerobotics.com/t/relative-positioning-of-jaws-on-newton-gripper/4864/4 "2019-04-18T02:35:56Z")
Do you have a servo tester or oscilloscope? The pwm signal is velocity control. The gripper should be stationary at 1500pwm, and full velocity at 1900/1100. ---
**Author:** ![etienne](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/etienne/32/1942_2.png) [@etienne](https://discuss.bluerobotics.com/u/etienne)\ **Post date:** [April 18, 2019, 3:01am UTC](https://discuss.bluerobotics.com/t/relative-positioning-of-jaws-on-newton-gripper/4864/5 "2019-04-18T03:01:20Z")
I have a scope. As I understood it, the gripper should only move when the button is pressed and not travel full. So I was a bit surprised it was behaving like this. I will have a look at the settings for Servo 3 which I am using. Maybe the stationary pulse is not 1500pwm. Cheers, E. ---
**Author:** ![deepak](https://avatars.discourse-cdn.com/v4/letter/d/7bcc69/32.png) [@deepak](https://discuss.bluerobotics.com/u/deepak)\ **Post date:** [May 3, 2019, 10:55am UTC](https://discuss.bluerobotics.com/t/relative-positioning-of-jaws-on-newton-gripper/4864/6 "2019-05-03T10:55:09Z")
Sir, I tried to install the newton subsea gripper in my ROV through pixhawk. It works but the jaws either opens completely or closes completely. I tried to check out for the options “max\_momentary” and “min\_momentary” as specified in the blue robotics documentation. But I couldn’t find these options in the latest version of ardusub i.e in ardusub version 3.5.4. All I could actually see were the options SERVOx\_min, SERVOx\_max, SERVOx\_center, SERVOx\_inc and SERVOx\_dec. I tried all these options one by one, but couldn’t get the expected result. Can you please tell me how I can control these gripper jaws perfectly in the latest version of ardusub. Looking forward for your reply. Thanking you, Regards, Deepak ---
**Author:** ![etienne](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/etienne/32/1942_2.png) [@etienne](https://discuss.bluerobotics.com/u/etienne)\ **Post date:** [May 4, 2019, 4:29am UTC](https://discuss.bluerobotics.com/t/relative-positioning-of-jaws-on-newton-gripper/4864/7 "2019-05-04T04:29:41Z")
I haven’t had time to progress further on this. Mine is either all open or all closed. ---
**Author:** ![jwalser](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/jwalser/32/2234_2.png) [@jwalser](https://discuss.bluerobotics.com/u/jwalser)\ **Post date:** [May 15, 2019, 3:30pm UTC](https://discuss.bluerobotics.com/t/relative-positioning-of-jaws-on-newton-gripper/4864/8 "2019-05-15T15:30:58Z")
@deepak, make sure you are using the latest version of QGC: [Downloads · GitBook](https://www.ardusub.com/resources/downloads.html) the servo\_max\_momentary options are there, lower in the list than the other ones you mentioned.