Asked — Edited
Resolved Resolved by Steve G!

Servo Slider Causes Crash

I'm new to EZ Robot, so maybe I'm missing something, but I don't think so. Have been using it for a couple of days now. Have a working app on my tablet and can operate from my desktop.

Today I added two "Servo Sliders to the "My Mobile Interface" on my PC and can operate the servos from there. However, when I save the file and download it to my tablet, the Ez Builder app crashes now when I try to open it, displaying the message, "unfortunately ARC has stopped working", then I acknowledge the popup by clicking yes and the app closes.

If I delete the servo Sliders, and download the updated app, it works again. So there seems to be an issue with the servo sliders working on the mobile app. Is this a bug, or am I missing a step to get them to work there as opposed to just working on my PC?




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United Kingdom

I never heard this kind of problem with the slider. What tablet and what OS are you using in which the app crashes? I'm wondering if deleting the app then reinstalling it may help.


Known bug. Dj is working on it. I'll post a link whebI am on my computer instead of my phone.



I've tried it on both my Samsung note 3 phone and my Samsung note 8 tablet. Unfortunately, both have the same operating system, Android 4.4.2.

Also, I did try deleting the the app and reinstalling it. I see above that this is a known bug. I don't have any other mobile devices, does anybody know of a work around, otherwise I don't have any means of controlling the direction of my camera. Is there perhaps another way of controlling the servo without the servo slider?

Thanks for anyone with some ideas.

United Kingdom


You could delete the slider and add left and right buttons to the mobile interface to move the camera servo. You could do it in such a way where when you press a button, the servo would move in small increments which can be set to what you desire. If you need a script example, let me know and I'll post one for you.


I don't use the mobile part of ARC at all, but if buttons can have scripts behind them you could use .... ServoUp() and ServoDown() commands to pan and tilt your camera....

ServoUp(D0,10) #moves servo D0 one direction 10 deg

ServoDown(D0,10) # moves servo D0 the opposite direction 10 deg

United Kingdom

I posted the examples for you anyway. If you add two buttons to the mobile interface, one for moving left, you can use the following...

#Assuming your using a servo on port D0

and for the right

#Assuming your using a servo on port D0

The part where it says "5" is the amount of position where a servo moves between 1 and 180, so you can change this to suit your needs. This way, every time you press one of the buttons, it will move 5 steps every time until it reaches the maximum set movement. The ">1" and "<180" can also be changes if you what the maximum servo positions limited. Hope that helps.


Thanks so much for all of your help. That's a great work around for the time being.

Excited to get on the the next step of my project.


United Kingdom

No problem. Glad I could help.