PAROL6 Desktop Robot Arm
github.com
github.com
You can sign up here for beta testers (there are a few spots left: https://forms.gle/sZqHVLPoMJxuVAyJ9 This is general form for people interested in control boards, kits, or whole robots: https://forms.gle/XkSvStwnQxw1f8xL8
My biggest question is the full cost for the PAROL6. Their BOM link is 404.
I can build the AR4 completely for less than $2000, and for education, that's a very small price for a semi-useful, full 6 axis arm. (Currently, to give a comparison, one of my suppliers is offering an educational cobot solution for $40,000. Yes, it's truly "industrial," and is a complete self-contained solution, though it's only capable of 2kg if I recall correctly. This was what they were pushing for the educational market.)
As someone who is trying to implement robotic training in education, with a budget that approaches zero, I just need something cheap that students can hack/break/fix without costing a fortune in maintenance costs.
One of the cool thing about the AR4 is that it can come as a complete kit, either as 3d printable or aluminum frame. and they work with Steppers Online to provide the steppers and drivers as one package. If you work for a school system, this type of solution solves a lot of logistical issues.
That said, if this thing is truly low cost, let's say under $1000, for it's capabilities, it could be a very nice project.
Looks like they forgot to update the link.
Being pedantic this isn't either, there's no CAD source files, only stl files. Hopefully that's just an oversight.
Usually CAD interchange is either in STEP or the program's proprietary format.
STEP is the sheet music, MP3 is the STL and the waveform is the gcode.
The CAD file, whichever format its in, is going to have all the solid modelling information and be much more useful if you want to make changes.
My major issue is that I can easily build stuff. The puzzle keep my brain on the job - but then I don’t know what to do after I’ve checked it works :D (i.e my various RC project are there, but then what ? I’ve built a rover, can do some automated stuff, but not very useful a the end…)
If the main purpose is for the robot to do something - the DIY approach is more likely to suffer issues that, without support, may discourage students because they're fussing with/fixing the bot instead of doing the thing.
Out of curiosity, what's the $40k kit you mentioned?
Educational packages are all over the place (some seem to be price-gouging, frankly) but the low-end (in terms of payload + reach) of commercial/industrial cobots is getting pretty affordable.
But I basically now operate in Bureaucratic Hell, and I have to figure out a way to get the equipment to teach my students. And due to changes in how my organization operates, ironically enough, I've found that getting the "professional/educational/industrial" products is often not the right decision.
One of the worst things that can happen is that we buy a $250,000 piece of equipment. The administration will never ever budget for the cost of maintenance, consumables, tooling, training, everything else required to successfully operate it. Within a year, you're stuck with a $250,000 piece of equipment sitting in a corner collecting dust, that is always shown to VIP's on tours as the latest in greatest in what we offer. Oh, and it's so expensive, we're not going to allow students to use it anyway, because we can't let them break it.
And it's amazing, they won't have funding for that $100 tool I need to teach the students and use everyday, but every year they'll manage to find $100,000 to spend, a week before the end of the fiscal year, which we have to spend immediately, but it can only be spent on certain items, like the things that I don't actually need. Welcome to public technical education in America. (Sorry, obviously, you unintentionally touched a nerve.)
But if I can get something that costs $2000, well, I can either fix it myself, or better yet have the students do it I will take something that I know is sustainable, that students can actually put their hands on and operate over that white elephant every day of the week.
In reality, this is all moot. No matter the cost, my budget is effectively zero at the moment. But I can hope.
The $40k was a Universal Robots UR3e I believe. The vendor put it on a cart as a portable, self-contained system.
If anyone has some pointers on other recent projects in the space, I'd love to hear about them!
As one can see the last commits are a few years old, and in the issues there are a few robot arms that I haven't worked in yet, which I want to do soon. However, I'd largely attribute the lack of activity to me not actually seeing a lot of new robot arms popping up. If there are any I'm missing or resources where one might regularly find some, I'm eager to hear about them and add them to the list!
Also the BOM info is gone.
Very impressive repeatability and very smooth movement for a 3d printed arm.
I wonder how the rigidity holds up over time. Working at a robotics company, the mechanical engineers had to overcome quite some challenges to find a compromise between, precision, speed and repeatability.
And that was with a metal frame.
If you're talking something like carbon fiber reinforced nylon, it's probably a bit better. If you move to something like Markforged's fiber-strand reinforcement it'd get even better. And then there are the SLA/SLS solutions, like Formlabs "rigid" material, which I think would be a very interesting material to try for this.
I think at the end of the day, you need to keep in mind this is an educational robot, not an industrial robot. If it can maintain 0.050" of repeatability, that would probably be good enough for a lot of use cases (but of course, that depends on your use case.)
Maybe this is a project where I can put the random collection of components to use which lying around in my basement.
Not exactly to spec but that's the spirit I think.
Quote from the manual:
> Screws are in this example M3 screws and holes are undersized to 2.7-2.8mm that means that when we screw in the screws we are tapping holes in 3D printed parts.
> There are multiple benefits to this:
> ● Connection is strongest compared to tapping holes with a tap or using brass inserts
> ● It is simple and fast
> ● No need to prepare the hole, it can be printed undersized
> Cons are that you can’t disassemble it a lot of times. In case you feel screws slipping in the hole. Put some super glue in the hole and wait for it to cure. After that re tap the hole.
If you have something you want to reassemble frequently, use inserts. If you're putting it together once and intend to use it that way for a long time, threadforming works fine.
Did they have any moving parts? Did they experience continuous vibrations and frequent mechanical shocks? For DIY robot arms, fasteners are very often the issue #1, if arms operated more than just for demo purposes.
You would be surprised how many screws will go lose after a a thousand of hours of operation, even in this case.
What I'm saying to you is to make sure something is an actual problem before saying it is. In this case, the fact that the screws are used as self tapping, the screws themselves create the threads, likely combats this. Like a nylock nut.
This isn't what I would do for say, a surgical robotics system, but that's not what this is.
If given the choice of having the design as is, or making it more expensive, more difficult to assemble, and less accessible. I'd choose it as it is.
There are always tradeoffs. I believe the designer made the right ones here.
Before saying they didn't, maybe build one.
[0] http://www.jeff-z.com/pinball/toys/armatron/armatron.html
It also highlights an interesting change in engineering and product development that has happoned in my lifetime.
It used to be, when this Armatron was made, electronics and computers were magic and mechanical engineering, real complicated kind of mechanical stuff, was common and the slillset to do it was similarly common. In that world it makes sense to have the whole robot arm powered by one motor that constantly spins, with mechanical clutches and linkages deciding what moves when. That's because electronics and mechatronics like motors and encoders were still expensive and new.
Now its the opposite. In general, if given the choice between a complicated mechanical solution and a "simple" electronic/computer solution we choose that. Simple is in quoted because modern electronics and computers are far from simple. The manufacturing of a modern semiconductor rivals the Manhattan project. But is seems simple because we can just buy it at best buy and program it to do things. You can easily find lots of engineers to do something with code or an arduino, but finding someone who can design a fly ball governer, or even know what that is and why it matters, is rare.
Now days there are tons of cheap robot arms that have a servo motor for each joint, because servos are cheap and complex mechanics are not.
Servo motors aren't cheap at all. Encoders aren't cheap either, in what universe do you live? The RC toys don't count by the way, because the cheap RC servos are terrible.
A fly ball governer? Is this some kind of joke? How are you going to operate it in any orientation other than upright? Why would you even want to?
There are probably ways to build a control loop with discrete electronics components that is cheaper than a mechanical system like that. Heck, it is probably cheaper to build an entire CPU with discrete components and then program that.
The reason nobody knows this crap is because it is useless. Your pseudo nostalgia for an age that existed before your time is ridiculous.
btw ultrasonic cleaners are like miniature dishwashers and having one near my office room is very convenient for cleaning hardware compared to using the full-size dishwasher in the kitchen. Only disadvantage is that it needs soundproofing
Fill with water & soap, insert dirty dishes.
Then when you head out for work in the morning, turn it on. let it buzz for 30 minutes or so, and then have a separate actuator drain the dirty water, refill and drain a second time as a rinse, and then drain again to let dry.
That would be what, $1200 in parts and a season of testing to make work?
I don't like the idea of having the dirty dishes right next to the clean ones so this would require at least 2 sinks so one can be loaded throughout the day
My desktop ultrasonic cleaner is so loud that I can't work in the same room. Transducers that can clean an entire sink (>10x volume) will likely be so loud that I can't work in the same building when it's running
If anyone in the building works from home, the unit will have to be soundproofed on all sides. That's way harder for a sink that's built into the countertop