Gate automation

[Norcon]

I have a cantilever lever slider gate with a Beninca gate opener fitted.
Fantastic gate but complete crap automation system. Never went right since it was installed 2 years ago. Gate being operated manually now.
I don't mind doing that but the problem is the lane is steep and if someone parks up and gets out to close the gate and the handbrake fails then they risk getting crushed.

Automation installer been back about a dozen times. Still trying him but phone now switched off.
Guy who made the gate said this was the best available.
Knowing what I do now I'd never have fitted the Beninca and would have designed something myself. It was an extra £1600.

I'm at the point where I want to rip this trash out and have another installer fit a different model. But the cost and reliability issues make me think again.


So I want to diy a gate opener. Something simple with electronics kept to a minimum. The infra red beams will probably have to go as they only add trouble imo.
Though I am open to suggestions as to how they can be incorporated in a simple manner.

I'm thinking of a small single phase electric motor coupled to a worm drive reduction gear box with a slip clutch built in and fit this to the gate.
That's the easy bit. I can do that in the while of an evening.

Then a timer relay set for a few more seconds than it takes the gate to close or open.
So when it closes the slip clutch operates. If it could be switchd off on a motor torqe sensing device or electrical overload then even better and have the clutch as back up.

I'd like a key fob also. So when its pressed again the gate opens.

 

[bernardgreen]

Automation installer been back about a dozen times. Still trying him but phone now switched off.

Try the Trading Standards Office.
.

The infra red beams will probably have to go as they only add trouble imo.

They are part of the essential safety system.

I'm thinking of a small single phase electric motor coupled to a worm drive reduction gear box with a slip clutch built in and fit this to the gate.
That's the easy bit.

The difficult part is making sure the gate cannot harm anyone when it operates.

A five-year-old girl was crushed to death by an automatic garden gate because it was faulty and did not meet British safety standards, an inquest has heard. Karolina Golabek died after she was trapped in a three-foot-high sliding gate for 30 minutes outside her home in Bridgend, South Wales, on July 4, 2010.
Read more: http://www.dailymail.co.uk/news/art...ate-pinned-half-hour-freed.html#ixzz2CIYxop3W

And a badly designed / installed gate can result in manslaughter charges.
http://www.mirror.co.uk/news/uk-news/two-arrested-over-childs-electric-233955

As it happens I am designing a mechanism for a pair of gates that will need to swing through 180 degrees and while the actuator is simple the safe control of the motion is not simple.

 

[chaindaisy]

Hi Bernard,

Some very valid, and valuable, points you've made there. An automatic gate without beams would be a bit of a 'no no' don't you think. I reckon there's room for legal proceedings against the guy who installed these gates. I am no designer Bernard, but perhaps you could consider a beam system which stops the gates at say a metre if an obstruction is detected at that point. Keep us informed on your project, it sounds very attractive.

 

[bernardgreen]

My system has to cope with keeping vehicles out of my property while allowing pedestrian acess to a shop on my property. They also need to be automatic for the vehicles permitted entry and swing inwards for vehicles entering and outwards for vehicles leaving. Ths two way swing is needed due to limited space both sides of the gate.

The main "defence" in my system will be an elastic coupling between motor and gate and detection where the gate actually is using positional feedback. This will enable the torque exerted on the gate to be measured and if it exceeds the safe limit then the motors will be stopped and reversed until the torque is removed.

This will allow for the gates to be opened wide enough for pedestrian access without allowing vehicles.. They can be moved by hand but this would create an alarm condition and maybe trigger a recorded anouncement to "Leave the gates alone"

It will also be a weak coupling slip if the motor continues to try and move the gates when the control system fails to detect the obstruction.

A gate to gate lock will hold them closed.

There will also be loops to detect vehicles in the swing areas.

It is a low priority project as there is still a lot of work to be done inside the cottage.

 

[Europlex]

Edit

 

[alumni]

Gate automation is serious business, legal wise.
It MUST be fitted according to regs. Get that wrong and if someone gets hurt the installer is likely to be spending time in the big house.
Cost is not a get out.

 

[chaindaisy]

Hi Bernard,

I'll overlook the infantile innuendo in a previous post above and get back to Norcon's problem in good time. Thanks for your description of your own gate project, it may well serve to give Norcon some extra ideas also.

 

[Norcon]

The main "defence" in my system will be an elastic coupling between motor and gate and detection where the gate actually is using positional feedback. This will enable the torque exerted on the gate to be measured and if it exceeds the safe limit then the motors will be stopped and reversed until the torque is removed.

If I'm reading this correct you are adding no motion sensors?

How will you measure the torque?

Would an overload relay not be sufficient to cut power to the motor?

 

[bernardgreen]

The angular positions of the motor output shaft and the gate itself will be compared which will give the amount of twist in the elastic coupling. That will give the amount of torque exerted.. The feedback of gate postion will also provide information that the gate has been stopped from moving by an obstruction and that power should be removed.

Using a motor over load relay would not be accurate enough to limit torque to a safe level if the gate was obstructed.

 

[Norcon]

Had a guy out today.
Snail was fried unto the pcb and blew the fuse.

He re-set some parameters also, so hopefully it will operate more efficiently than before.

I noticed he had an i phone and was looking at the settings from the phone as he did the adjusting which I thought was impressive.
Anyway its working now. For how long, time will tell.

 

[chaindaisy]

Hi Norcon,

Glad to see you're up and running again. At one time though, engineers used to look at their brains to 'see the settings'. Much more impressive than an iphone I reckon. What happens to this engineer when he's forty miles from base and left his iphone at home ? makes you wonder Norcon.

Take care mate.