Depends on the door handle. You might be able to use a servo, or you might need a motor and H-bridge depending on how much torque is required to pull the handle. (you could also use a pulley system to get a mechanical advantage with a lower power device like a servo).

Not to drive sales away from EZ-B, but a single function like this is probably less expensive to do with a Raspberry Pi or even an Arduino depending on what you want to use to trigger the door to open.

Alan

Hello Tech Tech Guru, Thank you very much for quick response. It is true that a single motor can do this single function. I wanted to do some "show off ! " hence the idea of a robot.

What I imagined in that a robot arm base is stuck to the lower part of the door.

1-) The arm makes a movement to reach the handle; 2-) Then gripper to touch the handle; 3-) then a gesture of 60 degrees to move it down 4-) Then make a sound: you can now push the door to the person who's outside;

Instead of playing around with servos and have cables all over. I thought to use some ready to use arm that can store the gesture and use it .

As for trigger, remotely either z-wave or wifi or anything that can allow easy control !

Thanks

The reason I ask about trigger is that the EZ-B needs to be connected (via WiFi) to a PC or smartphone at all times to operate. Getting a signal to it that the door needs opening could either be done through a sensor on the EZ-B or something that the PC could detect (like proximity of a Bluetooth device).

A long enough robot arm could give you the mechanical advantage needed to just use a servo as the control. You will probably need to experiment some. Do you already have an EZ-B?

Hello Guru !

I don't have a EZ-B as yet as I am just starting working on the idea . This is for my guest house whereby when I am not here, I wanted to get them have door opened spectacularly. I will put keypad outside and find a way to send signal . Does the EZ-B integrate with any arm or is it part of the existing set ?

Thank you so much fo ryour lights

EZ-B integrates via digital ports. If hte arm is servo based, you can plug in directly. If it has motors, you may need H-bridges.

Alan

you need to know your hardware options, let's start with EZ-B the only known part so far:

There's more than one way to skin a cat, sorry cat lovers

you can control analog servos, digital servos (Dynamixel), you can use UART to communicate with an external controller or you can use I2C.

i see a few options:

1. open/push the door

handicap door opener

http://www.aliexpress.com/item/Handycap-openers-for-doors/2034195952.html

the solution is a motor, controller and remote. You can hack it: 1.1) using the motor 1.2) via controller if there are visible digital pins 1.3) via infrared (remote controller).

buying a kit like that, gives you some relief,you don't need to build mechanical extra parts, you can exchange some tips with the manufacturer about you port weight, open directions, and other stuff.

2. electric lock

you will need a electric door strike

http://www.amazon.com/Electric-Mechanism-Security-Intercom-Systems/dp/B00164SFFQ

and you will need to adapt to the existent door, there are some combinations allowing manual (handle) and automatic (electric).

with some work/luck you can power both devices with a single source 12V.

if you decide to interface directly to the motors (door and strike) the cheapest and easy solution is to use a darlington transistor like a TIP 120 or similar, there some adjustments but you can have an idea from here:

http://bildr.org/2011/03/high-power-control-with-arduino-and-tip120/

you can use a H-bridge (Alan response) but is not need unless you want the motor to rotate different directions.

The speed can be controlled via PWM.

This is the easiest implementation and probably the cheapest more or less $500-$600 if you add the EZ-B.

If you want the wow effect via an Arm Robot, prepare to spend some money on heavy/powerful digital servos plus some heavy robot base to push the door.

I can extrapolate more, but if you are serious to build something like that is better to define a budget.

Tiago,

Thank you for all thorough links, I went through all o fthem. It is great to see such reactive forum with passionate ... Let me tell you more about my idae and where it came from.

Basically, I run this guest house where guests arrive anytime, it can be midnight and I thought I would need a Door Access Control system, with temporary codes for each of the guests. As I looked at the prices of descent system , I realised maybe for the same budget ( less than 2000 USD), I can do something more spectacular using robot or something out of the box . Which is not necessary an electronic classical door lock. So here is what i thought, a few ideas ( maybe I'm too much of a dreamer :-) ) :

1-) Get some nice design robot like the Ez-Robot or other ( which impresses with its look) and let it come out of a window , which is on top of the door. It will hold an envelop with key code for instance or a key that it can throw to guests, who will be totally surprised to see a robot coming out unexpectedly from the top of this old looking house door !

2-) Other possibility is to put a Robot Arm on the back of the door around a classical handle. It would do a gesture to open the door by playing with the door handle and give some speach like welcome with name of guests. This is triggered after the guest has said he arrives and I send command via wifi or z-wave or any other mean;

3-) Even more crazy , but less realistic, get a robot come down from a rope from top of the door with keys in its gripper to handle them to guests ;

4-) Any other that follows same spirit ! A fun, spectacular stuff for this budget that does the job of handing the keys or opening the door to the guests

So, budget is 2000 USD max for something worth. Allow me to dream as I don' tknow much about technicallities of robotics today. I just want to take some almost ready to use components and put them together to come to this result !