where to start??

[dsmvalley]

hi there, new to the electronics forums.........i have a project that i need to figure out a decently affordable solution for as I need to build 5 or six of these units. basically i need some form of sensor(s) to detect an object, then actuate a 120V appliance. the appliance will move the object and the sensor will kill the 120V feed.

i have looked at infrared, garage door and proximity sensors, but my electronics knowledge is limited ...........

thx in advance!!!!!

 

[Mr RB]

Please provide more info... what object? how is to be moved? how often? etc.

 

[dsmvalley]

THANKS for responding Mr RB!!

basically its an automatic trash can..........the bin will contain a canister vacuum and be elevated about 4" off the floor, and trash will get swept into the space under the cabinet holding the vac. The "object" will be trash, specifically hair. Once the hair is detected, the canister vacuum will actuate and suck up the hair.

size of the detection electronics is somewhat important as I would like to have them take up as little space as possible.

 

[Mr RB]

Sounds like a fun project.

I would use one of the Sharp 30cm distance sensors; GP2D120.

These will detect anything within about 30cm and output a analog voltage that gets higher when something gets closer.

So you need a GP2D120, a voltage detector (like a comparator IC) and a relay etc to drive your vacuum.

Then set up the mechanicals of the detector so it detects anything on the floor thicker than 1" like a matt of hair, or the broom etc.

 

[dsmvalley]

sounds great!.........this a good starting point at least. I am pretty green to creating circuit boards and looking for sources of the parts you mention. Any thoughts on a vendor that might have the parts that you mentioned??......I assume that the parts can be easily found and configured??............thanks again!!!!!!!!

 

[Mr RB]

The sensor is fairly easy to get now from a few places;
Sharp GP2D120 IR Sensor
Sharp GP2D120 IR Range Sensor - 4 to 30 cm - RobotShop.ca
Pololu - Sharp GP2D120XJ00F Analog Distance Sensor 4-30cm
**broken link removed**

As for the comparator and maybe a 555 timer IC and a relay, they can be sourced from just about anywhere. Hopefully someone else will comment, they may have better ideas on how to do it too.

 

[dsmvalley]

sounds good I appreciate that Mr RB, any other thougthts out there by chance??

 

[colin55]

Just get someone to hit the can with a broom and use a 30 cent piezo to detect the noise and operate the equipment.
I could tell you to use 3 microcontrollers, like the University professors suggested to drive a few LEDs, but I like to keep things simple - and not look like an IDIOT.