IR sensors

[CPUguy387]

THANKS! I just wanted to make sure, since I really don't feel like desoldering (it's such a pain!) Also, thanks for reminding me to switch pins 2 and 3, I never would've known (except when it didn't work!) Thanks again

[Phil_Lutz]

You have enough parts to build 2 beacons. Those beacons are placed on the center line of the playing field. Build one and power/controll it via your edubot.

That's the transmittor.

You then need to build the receiver for your robot.

[CPUguy387]

Where can I reorder another FET? One of the ones I had broke when I was trying to desolder it and switch pin 2/pin 3

[Kevin Watson]

Originally Posted by CPUguy387

Where can I reorder another FET? One of the ones I had broke when I was trying to desolder it and switch pin 2/pin 3

Digi-Key has 'em. The part number is IRL3103-ND.

-Kevin

[Matthew_H]

What is the exact size that we cut the victorboard? If there is somewhere I could find it, that would be great.

[Mark McLeod]

Originally Posted by dmellich

Let me see if I have this straight.

The IR beacon parts in the kit are enough to build the two units (one for the robot and one at the balls). The EDUrobot controller is used with the beacon unit at the balls. Only thing left to do is use the appropriate code for each side.

The beacon parts are for the two beacons that will be on either side of the field. Neither gets mounted on the robot itself. Drive the beacons with the EDU controller running the beacon software provided at the IFI web site (labeled "IR Tracking Code - Kevin.org").

The robot gets just the one piece IR sensor (4 are assumed in Kevin Watson's code) hooked directly up to digital inputs 1-4. Drive these with the navigate software also in the download above.

[CPUguy387]

We ordered 2 more FETs just incase. Before I put the one on my second beacon, I just wanted to make sure which digram is correct. Is this one still wrong? http://www2.usfirst.org/2004comp/Inf...ng_diagram.pdf Should I still reverse the pins 2 and 3? I just wan to make sure again before I order more.

[Mark McLeod]

Originally Posted by CPUguy387

We ordered 2 more FETs just incase. Before I put the one on my second beacon, I just wanted to make sure which digram is correct. Is this one still wrong? http://www2.usfirst.org/2004comp/Inf...ng_diagram.pdf Should I still reverse the pins 2 and 3? I just wan to make sure again before I order more.

That circuit is incorrect.
Luckily the FET seems to be internally protected against hooking it up incorrectly or teams would have been burning them out right and left.

On the FET looking at the front (with the metal ground plate at the back)
pin 1 on the left goes to the white (signal) wire on the PWM cable from the EDU controller.
pin 2 goes to the negative side of the circuit you built.
pin 3 goes to the black PWM wire (common or ground) from the EDU controller.

You can see an updated circuit diagram Kevin Watson posted at http://kevin.org/frc/ beacon_transmitter_2.pdf

You can only see your circuit running with a digital camera, or by hooking up one of the IR sensors to a digital input like 6 and adding a printf to print the value of rc_dig_in06 in the beacon code.

[Oode]

Originally Posted by Mark McLeod

That circuit is incorrect.
Luckily the FET seems to be internally protected against hooking it up incorrectly or teams would have been burning them out right and left.

On the FET looking at the front (with the metal ground plate at the back)
pin 1 on the left goes to the white (signal) wire on the PWM cable from the EDU controller.
pin 2 goes to the negative side of the circuit you built.
pin 3 goes to the black PWM wire (common or ground) from the EDU controller.

You can see an updated circuit diagram Kevin Watson posted at http://kevin.org/frc/ beacon_transmitter_2.pdf

You can only see your circuit running with a digital camera, or by hooking up one of the IR sensors to a digital input like 6 and adding a printf to print the value of rc_dig_in06 in the beacon code.

Unfortuantely, even with the wrong circuit, you will still see the LEDs glow in the camcorder, in fact, the circuit actually functions with the Source and Drain swapped, but the resistors get REALLY hot. ( I tested it with the IR reciever and a scope, and the signal is there, just not as clean and not as far a range)

So why won't First fix the document error?????