# Cannot find local position estimator parameters **URL:** \ **Category:** PX4 Autopilot\ **Created:** [July 7, 2016, 6:38pm UTC](https://discuss.px4.io/t/cannot-find-local-position-estimator-parameters/672 "2016-07-07T18:38:49Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![pchatrath](https://discuss.px4.io/letter_avatar_proxy/v4/letter/p/54ee81/32.png) [@pchatrath](https://discuss.px4.io/u/pchatrath)\ **Post date:** [July 7, 2016, 6:38pm UTC](https://discuss.px4.io/t/cannot-find-local-position-estimator-parameters/672/1 "2016-07-07T18:38:49Z")
I installed px4 firmware on my pixhawk using qgroundcontrol. I want to connect an optical flow kit to the Iris+ uav. As per the [dev.px4.io](http://dev.px4.io) documentation I need to change local position estimator parameters like - LPE\_GPS\_ON. However I do not have any lpe parameters on my pixhawk. Why? Is my px4 firmware not the latest? ---
**Author:** ![Mark\_Whitehorn](https://discuss.px4.io/user_avatar/discuss.px4.io/mark_whitehorn/32/3533_2.png) [@Mark\_Whitehorn](https://discuss.px4.io/u/Mark_Whitehorn)\ **Post date:** [July 8, 2016, 1:50pm UTC](https://discuss.px4.io/t/cannot-find-local-position-estimator-parameters/672/2 "2016-07-08T13:50:34Z")
Use the current stable version of QGC to install the stable version of the PX4 firmware. Make sure you choose LPE using the system parameter SYS\_MC\_EST\_GROUP. If you still don’t see LPE parameters after a reboot, try flashing the master version of the firmware instead. ---
**Author:** ![pchatrath](https://discuss.px4.io/letter_avatar_proxy/v4/letter/p/54ee81/32.png) [@pchatrath](https://discuss.px4.io/u/pchatrath)\ **Post date:** [July 8, 2016, 2:42pm UTC](https://discuss.px4.io/t/cannot-find-local-position-estimator-parameters/672/3 "2016-07-08T14:42:20Z")
> [@Mark\_Whitehorn](#): > > SYS\_MC\_EST\_GROUP Thanks @Mark_Whitehorn. I dint know about SYS\_MC\_EST\_GROUP. Setting that parameter did the work for me. Now I can see all the lpe parameters. Thank you