When building a robot one needs to use sensors. I used sonar sensors before for this post:
The main idea is to get rid of the Arduino on our rover “Scarabeus” and use the sonar sensor directly on the BeagleBone. The problem is that this sensor needs a 5V pulse to trigger ultrasonic output and it also answers with a pulse according to the received incoming signal but all the GPIOs on the BeagleBone operate at 3.3V. There are several possible ways to solve this and I’m presenting two of them here.
- Do some electronic hack and apply the sensor directly onto the BeagleBone.
- Use a dedicated 5V chip to handle the sensor and communicate via serial port (uart) to the BeagleBone.
This article will describe the first one, the direct approach. (more…)