I’d have thought the access control would be wired into the machines themselves, rather than the power supply. Use the interlocks if they exist etc.
I imagine some machines wouldn’t like having their power supply interrupted at the wall too?
Actually quite the opposite, we intend to have contactors on the wall by the fire exit that control each tool, these contactors will make and break the power to each socket.
All the tools will be fine, they have an NVR which means when power fails they handle the power failure, almost all the tools work this way. The idea they had was that we don’t know where stuff is going so it’s best to put everything in a movable way.
Sure I understand the need for flexibility. It just seems obvious to me to include the access control on the machine itself, so everything’s self contained? Plug it in to any socket and the access control will work.
I won’t push too hard here; you guys obviously know what you’re doing 
I agree Tom… @joeatkin2 Tom is making a good point that simpifying it so the contactor is on the tool means less work. Then it’s just a 16A connector into our box, and an RS485 connection.
Also it would make sense to me to use the machine’s own power control circuits if possible so you don’t have to build boxes that can switch 16A.
I agree with Tom^2.
Part of my thinking is when we get inspected if we have 240 in a box with home made stuff there is a possibility that the inspctor might just say "No and i will not talk about it "
I have seen it happen before
Also if anything can be plugged in anywhere it definitely adds vast amounts of flexibility so tools can be moved around and to make way for big cuts and long nits of wood .
It will effectively increase the amount of space buy a large margin
The options are:
-
Fixed tools with remote power control
Requires local controller to signal to remote controller where the contactors are, with one RFID reader. -
Movable tools with remote power control
Requires local controller to signal remote controller where the contactors are with two RFID readers. -
Fixed/movable tools with local power control
Requires a local controller and RFID reader that has it’s own contactor.
The third option is way simpler, none of this embeding RFID in the socket… Just put a box on each tool that controls it’s power and has an RFID reader. We can then still have movable tools without the fuss.
The big fixed stuff yes possibleey it makes sense but small dangoros hand tools there’s nowhere to put it and it also means tools would have to have much bigger workstations. We can make the mitter saw bench half the size if it can be moved for a long cut .
I don’t think that we have the space for a fixed system
I don’t really understand the problem. Tool control is fairly standard, and so long as we don’t do anything really idiotic, we’re just doing a slightly more fancy PTM in line with the existing on button on the machine.
I would assume that building the contacter into the machine similar to laserbot would make the room the most flexible possible. but then I assumed the tool control would all use Wifi or something generic.
Some of the options require a much bigger workshop. And don’t control the hand tools wich are just as dangerous
for example?
Yes thats true, but we can control who can take out a Skillsaw or Jigsaw using the digital locker idea I suggested…
Skill saw ?
Router ?
Ect
All much more dangerous than the big fixing to the floor stuff
I am not advocating fixed, but putting something on the tool resolves this issue?
Skill saw biscuit cuter plane
Slill saw is a table saw that you can stuff in your face or someone standing next to you .
As is the router
It still makes the workshop half the size .
And ee must not conflate the tool control with the interlocking system . As you said if someone defeats the toolcontol yhen the interlocking system is also defeated . As with the nvr .
Ad you said that hackspace has to have antitampot systems .
And as for wifi how do we implement it . Without risking people getting hurt.
a single separate system that is central and dose not involve mucking around with the factory safety systems is central to the plan.
And if someone bypassis it it there should be no possibility of also buy passing the interlocking .
This is slms every one knows how to do it , if someone wants to buypasd the system it eill happen and it is very important that the next udet doses not loss a hand .
Conflating safety and security systems is very very dangerous.
Ps it took me about 2minits to defeat the laser bot the other day when we lost the intrnet .
Clappm rail crash happened because someone did not tape up the end of a cable. And that was a fail safe interlocking system that took years to engineer and it was defeated by low pay and no pvc tape .
We have to be reley carful about inplementing safety systems that can kill people . It would probably be better to have no access control tnan dangerous access control
I don’t think this is the same thing…
We are not talking about replacing the safety systems of the tool, so we are not making it dangerous, it couldn’t possibly turn on by its self, so there fore it is no more dangerous than normal.
The control box its between the tool and the power socket and controls who can turn it on.
From a high-level POV, I’d have thought that if someone circumvents a security device then SLMS cannot be held to blame for any subsequent injuries. “We told you not to do it, we tried to stop you doing it, but you did it anyway. Your fault.”
No system is foolproof; anything we build is basically a way of encouraging trust, rather than enforcing a law.