Well, I will start directly in my problem. I'm working on a project and I only have 10 days left. The idea is simple, a wheeled robot with 3 ultrasonic sensors to avoid obstacles. I've developed a code and it's working fine. I'm using: Arduino Uno, L293D driver for the 2 dc motors, 3 HC-SR04 ultrasonic sensors and the Newping library.
I've made some kind of a shield where I soldered common points for gnd and 5V in order to connect the L293 ic and the sensors pins easily. The problem is that the ultrasonic sensors only functioned once in the expected behavior! After that they were always sending the zero result and sometimes a number is showed when i disconnect the sensor! Is it a power problem? I'm using the usb cable to power the arduino and the sensors (motors are powered using 2 Li-po batteries) kindly provide me with guidance