So I started building this 3D printed Bluetooth robotic arm that can be controlled via MIT app inventor from HowToMechatronics.com. After connecting all the servos and running the code, the servos seem to be jittering and doesn't follow the orders from the app. I have tried to increases the voltage from the external power supply and have also tested each servo individually but the outcome however was the same. Please do let me know if you have any suggestions or advice regarding this issue, I would be happy to try them out.
This is the link for the codes: https://github.com/darren-noyce/RoboticArm.git
If someone could help me to understand what's wrong, I would greatly appreciate it. Thanks.