Obstacle detection with Ping))), Propeller Servo Controller USB & Roborealm

honor_the_ways

I purchased a Propeller Servo Controller USB (http://www.parallax.com/Store/Accessories/MotorServoControllers/tabid/160/ProductID/595/List/0/Default.aspx?SortField=ProductName,ProductName) to use along with Roborealm to get a robot to visually track a target. I also need to hook up some PING))) ultrasound sensors to do additional obstacle detection.

From what I've read here and other places (http://forums.parallax.com/showthread.php?94501-interfacing-the-ping!-ultrasonic-rangefinder-directly-to-the-PC&p=650963&viewfull=1#post650963) it seems that I would need a microcontroller in order to control the PING))) and read values from it.

Is there a way to use RoboRealm's Serial module, or any other module, to do serial coding in order to send the appropriate signal to the PING))) and read the return value without a separate microcontroller unit?

Mike Green

Yes, you need some kind of microcontroller to control the PING))) and provide values based on the "time of flight" echo pulse from the PING))). The Propeller Servo Controller USB is a very capable microcontroller that can control servos, communicate with a PC over the USB serial port, and handle one or more PING)))s as well. What you'd have to do is modify the firmware in the Servo Controller to respond to an additional command which would be used to trigger the PING))) and would respond with a number derived from the echo pulse. The firmware is open source and there are routines in the Propeller Object Exchange that will handle the PING))) that can be combined with the existing firmware.