Looking for a new Photo Sensor
 

We are looking for a digital photo sensor. We previously had the Allen Bradley right-sight 42EF-DIMNAK-A2. Is there any way to modify it to make it a digital sensor? Or, does anyone know of a good digital photo sensor? Thanks!

Re: Looking for a new Photo Sensor
 

What makes you believe it isn't a digital sensor?

Re: Looking for a new Photo Sensor
 

When testing, we were getting a range of values rather than just 1 and 0. We're working on it right now, but from what we can tell, it doesn't return boolean values in the code.

Re: Looking for a new Photo Sensor
 

How do you have that 42EF-DIMNAK-A2 wired to your roboRIO?

... and how are you reading it in your code?

Re: Looking for a new Photo Sensor
 

The 42EF-DIMNAK is digital, but it is designed for operation using 10.8 to 30V, not 5V. See this thread for more details.

Re: Looking for a new Photo Sensor
 

In a general context, however... and note that there are likely better solutions in this specific case based on what I've read above... but in a general context you can turn an analog input into a digital output by using a comparator https://en.wikipedia.org/wiki/Comparator

There are a number of cheap op-amp/comparator chips out there... you feed your analog sensor into one input on the comparator, and use a potentiometer as a voltage divider on the other input to provide a reference voltage. When your input voltage exceeds the reference voltage, your signal goes high (or low, if you want to hook it up that way).

Google a bit and you'll find sites like this http://home.cogeco.ca/~rpaisley4/Comparators.html but maybe check out some of the options above before using this solution in this specific case.

Jason

Re: Looking for a new Photo Sensor
 

Megan - For a digital photo sensor, we like the DFRobot IR sensor, it is adjustable to trigger at distances from 3 to 80 cm. Runs on 5VDC for $7.50. Part number SEN0019, DFRobot.com. No affiliation.

We can give you one of ours if you like, so you can try it out. PM me or contact us through team836@robobees.org.

Re: Looking for a new Photo Sensor
 

AutomationDirect has lots of different kinds of photo sensors.

Use your KOP voucher to take $30 off ...

AutomationDirect Sensors

Make sure you order an NPN output version and that it runs on 12Vdc.

Re: Looking for a new Photo Sensor
 

Seconded. These are nifty little doodads. Reminds me that I need to order some for some automation tasks on the robot....