RFID Door lock

[gamefreak]

i dont think i'll ned a regulator, the BOE has a built in regulator and 3 VIN pins so i can choose between regulated and un-regulated. Also if my batterys dont holf a charge long enough i can figure out how to use MOSFETs and hook up the servo to it

[gamefreak]

Alright i bought a door latch sanded it down a bit to make it flat and epoxied a servo onto it, but im using http://www.parallax.com/detail.asp?product_id=900-00008 and im not sure if its enough torque, i came to the conclussion that if it isnt then i'll modify the code to make it turn just enough to move the latch but so that it doesnt go into the indents that keep the latch from beign pryed open

heres a bad diagram of what i mean, the latch has two indents(indicated by the gaps) that stop it from being forced shut, it requires a little bit extra torque to start the unlocking but for the rest it is pretty minimal, so i figure if it cant get the latch out of the indents then dont let it, will this work?
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[Admin]

haha you diagram was too bad, i cant picture it

what is resisting the rotating servo? perhaps you can grease up the joints or make the moving lock thingy a loose fit?

the best way to test required torque is to get a stick of X length, attach it to the part on the lock that rotates, then add weights to the end of the stick. keep increasing the weight till the lock turns.

weight * X = minimum required torque

[gamefreak]

Well i epxoyied the servo on and i geuss i got lucky, i preprogrammed the continous rotation servo to turn about 180 degrees, if i hold the servo and latch the it turns just enough to lock/unlock the latch if its not in the ditches

Also i bought a 8.4 volt NIMH battery pack today and it has a "Deans Ultra" connection, do i need a special charge for those or will any old NiMH charger work?
and to hook it up to the BOE, from parralax should i just take two jumper wires and connect it to the 9v battery spot? sorry for all the questions.

here are the ditchs/gaps im talking about:

[Togo5]

i once made a lock and i thought it worked quite well.

i made an electromangnet using a soft iron core, then attatched it onto the door. in line with it (the 'latch') i used a magnetic rod. to lock the door i switched the + - to make the magnet repel the object thus moving the latch right into the stopper locking the door.

to open the door is just simply swiching the leads again to use it as a normal electro magent with it attracting the rod and freeing the door

just thought you might wanna hear other possibly ideas  i think it worked really well for such a simple idea.

[zamboniman60]

If you're going to be using this in a stationary application, like pemanently attached to a door, wouldn't it be a good idea to just find the right wall transformer/rectifier/filter box and just run a long wire?

[Admin]

Also i bought a 8.4 volt NIMH battery pack today and it has a "Deans Ultra" connection, do i need a special charge for those or will any old NiMH charger work?

I agree with zamboniman60's suggestion of using a plugable power supply . . . anyway, 8.4V is a little odd, but any NiMH charger that says it can do 8.4V will work fine. but for the connector . . .

the Deans Ultra connector is really odd looking


you can always solder some wires on to it, or cut it off and change the adaptor . . .

and to hook it up to the BOE, from parralax should i just take two jumper wires and connect it to the 9v battery spot? sorry for all the questions.

you mean connect the 8.4V battery to the power connection labeled 9V on the boe bot? if so, then yes.


again, I would just get a power supply you can plug into the wall . . .