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scorpions980
01-02-2010, 16:50
can someone please tell me where the ultrasonic sensor gets plugged into.
thanks in advance

Bryan Herbst
01-02-2010, 16:52
It depends on what type of sensor you have.

If you are using a Lego NXT ultrasonic module, then it goes into the I2C bus that looks like a phone jack.

Most other ultrasonic sensors will use the analog inputs on the analog breakout.

To determine how exactly you wire it all up, you will have to consult the senor's data sheet.

Tom Line
02-02-2010, 00:55
Let me give you a warning about most ultrasonice sensors if you haven't used them before:

They do not have a fast enough response time to look at a ball or other robot as you close to really prevent a collision. The maxbotics sensor we used in 2008 lagged behind so much at the speeds we were running (13-14 FPS) that we had to tell it to stop the robot when it saw something at 6 feet ahead. There is a significant lag introduced throught the ping / process / analog signal process that you can only get a handful of updates a second. Move 15 feet in that second and you can see the problems.

If, however, you are using the sensor to try to see how far away the back wall is, you'll need to be careful that your beam is narrow enough that it doesn't pick up the bumps. The narrowest I remember was on the order of 2 feet or so.

kamocat
03-02-2010, 00:32
The ultrasonic sensor that Lego sells is not actually I2C compatible. It will not work with the Digital Sidecar. All HiTechnic sensors that have been tested have worked with the Digital Sidecar.
He's not kidding. I was unable to get the Ultrasonic Sensor to respond to a single message.