[brainchild]

 rogrN2.jpg (147.61K)
Number of downloads: 58

For two years I've been working on a project I call "RoBLOKS". The principle is to build a system of modular robotic units that can be scaled or combined to perform nearly any function. The former-titled LLCNC machine was (ironically) being made to create the RoBLOKS pieces, yet I never considered it a part of the RoBLOKS system, until now that is! In building the machine, it came to embody the very things RoBLOKS is all about, and in a flash of inspiration, RoGR was born. RoGR stands for the "RoBLOKS Gantry Robot".

Because RoGR is extremely adaptable, and since RoGR uses many of the same parts that are used throughout the entire RoBLOKS system, and because RoGR can be used to make more RoGRs, or more RoBLOKS, I think it is only fitting to give RoGR the designation of RoBLOKS Module #1. Read the RoBLOKS page.

RoGR bearing kits are available

RoGR Servos kits are available


 LLBKV1.jpg (317.15K)
Number of downloads: 99

[brainchild]

Cut list beta; 6061 aluminum. Don't buy this until RoGR is done: Est 10/08


2 pieces

.5" x 10" x 12"

1 piece:

.75" x 3" x 6" (Z motor mount)

1 piece:

.5" x 6" x 11" (Z back plate)

1 piece:

.5" x 6" x 16.5" (Z front plate)

2 pieces:

.75" x 2.5" x 6" (Z shaft supports)

2 pieces:

.75" x 6" x 6" (Tool holder) beta

[brainchild]

Alright, so tonight I took a few vids of RoGR "JR." RoGR JR is the weak iteration of RoGR yet has been cutting Q parts non-stop, and in these vids, RoGR JR is cutting out a Q42 back. This is the "lesser machine" with 40" of X on 20mm rails but the RoGR JR never fails. For the RoGR final iteration, I increased the rail sizes, switched to recirculating linear bearings, made it much easier to build, decreased the price by $3k, and expanded the functionality tremendously.

A video of the "forward looking" control software programmed for RoGR:



Coordinates:



The weight and pulley that manages RoGR's cord:



Cutting a Q42 back:



Repositioning:

[joecnc2006]

EMC2?

[brainchild]

joecnc2006, on Feb 28 2008, 12:26 AM, said:

EMC2?

http://www.linuxcnc.org/

[brainchild]

Well, I awoke way too early with the realization that I could save some weight and machine-ops by re-engineering the gantry to a "split-block" design. The gantry is still 2.5" wide where needed, but the split-block design allows for easy "ways-clearance" by using any regular CNC router (no milling/ precision drilling), and cuts the weight of the gantry by some 6lbs.

A few pics (thanks Robin!) to illustrate:

 newgantry1.jpg (210.08K)
Number of downloads: 215

 newgantry2.jpg (92.39K)
Number of downloads: 3793

 newgantry3.jpg (83.9K)
Number of downloads: 110

[Hirudin]

Do you think this would be possible: Build this temporarily with MDF/t-slots, then use the temporary build to cut and drill the aluminum? Maybe even replace parts piecemeal (for instance, use the MDF machine to cut/drill/route the gantry split-block, then install the new aluminum split block, after that continue machining and replacing the parts until no MDF is left).

This post has been edited by Hirudin: 01 March 2008 - 07:53 AM

[brainchild]

Hirudin, on Mar 1 2008, 02:53 AM, said:

Do you think this would be possible: Build this temporarily with MDF/t-slots, then use the temporary build to cut and drill the aluminum? Maybe even replace parts piecemeal (for instance, use the MDF machine to cut/drill/route the gantry split-block, then install the new aluminum split block, after that continue machining and replacing the parts until no MDF is left).

I do.

Also, I am coming out with "micRo", a smaller machine that when finished will cost about $500, and is the same billet construction. I'm designing it so that all of the parts are interchangable with RoGR, but the micRo billet parts can be made entirely on a drill press. micRo can used to make the machined pieces for RoGR, then the parts from micRo become RoGR's Y and Z axis.

[Hirudin]

Cool!

I just got another idea... What do you say to someone, like me for instance, paying for the bearings, bar things, motors, screws, and shipping now, but waiting until you have everything so the shipping is less?

[brainchild]

Hirudin, on Mar 1 2008, 03:52 PM, said:

Cool!

I just got another idea... What do you say to someone, like me for instance, paying for the bearings, bar things, motors, screws, and shipping now, but waiting until you have everything so the shipping is less?

Absolutely. We'll work with you however you need. I'll have the motor kits ready for sale in about a week though (motors coming in same container as bearings). It's almost certain that the entire kit will be ready to ship by the time the bearings get here.

[Hirudin]

I'm crazy, I ordered a set of bearings!

This is surreal for me... I pretty much cannot believe I'm going to have one of these at my disposal.

If you're still on the fence go search for "cnc" on YouTube, it wont be long before you're convinced

[NinHowFritz]

You may want to put some kind of cover over that exposed threaded rod. If metal shavings get into the carriage part, it might sieze up after a while...

[Maarten]

NinHowFritz, on Mar 2 2008, 01:49 AM, said:

You may want to put some kind of cover over that exposed threaded rod. If metal shavings get into the carriage part, it might sieze up after a while...

Indeed, I think it also

Nice work! Really respect!

[brainchild]

NinHowFritz, on Mar 1 2008, 07:49 PM, said:

You may want to put some kind of cover over that exposed threaded rod. If metal shavings get into the carriage part, it might sieze up after a while...

There are "screw wipers" to prevent this. The machine we run now doesn't have them though, and never has problems. The nut/screw fit is too tight to allow chips to get in...and of course, we keep it lubed with "shedding oil" which allows the chip to fall off.

[Hirudin]

Are the dimensions of the bearings available? Or better yet, do you have them modeled in 3D already?

Actually, can we have the full 3D model?

This post has been edited by Hirudin: 02 March 2008 - 09:40 PM

[brainchild]

Hirudin, on Mar 2 2008, 04:21 PM, said:

Are the dimensions of the bearings available? Or better yet, do you have them modeled in 3D already?

Actually, can we have the full 3D model?

Yes on both accounts. The drawings are being reworked now to reflect several last minute changes. When we're done, probably this week, I'll post them, as well as any g-codes, drill files etc for making the pieces.

[NinHowFritz]

brainchild, on Mar 2 2008, 02:09 PM, said:

...and of course, we keep it lubed with "shedding oil"

Some lube is always good

Another question, if you don't mind Is there some kindof anti-backlash mechanism on there, or is it a tight enough fit that backlash isn't an issue?

[brainchild]

NinHowFritz, on Mar 3 2008, 03:15 PM, said:

Some lube is always good

Another question, if you don't mind Is there some kindof anti-backlash mechanism on there, or is it a tight enough fit that backlash isn't an issue?

Backlash on the nut? You could preload or "side bind" the nut, but it isn't necessary. For the ways, I have decided to embed a bronze bush and set screw in the center of this piece.

 newgantry3.jpg (83.9K)
Number of downloads: 110

The set screw can tension the bush against the ways, eliminating any lash in the gantry assembly in a linear fashion. Better than shimming bearings!

[joecnc2006]

Preloading is the method of eliminating backlash in a ball screw assembly. This is accomplished by the use of one group of ball grooves in opposition to another to eliminate backlash. Preloading increases stiffness (resistance to deflection) and provides for accurate positioning with very little increase in applied torque or load capability.

This is if you use a Ballscrew, If you use a nut type you will need to provide an auto adjusting backlash compensator. I.e a spring or such, Look at Dumpstercnc's antibacklash nuts, I use them and they work very well.

Joe

[Epic Proportions]

What do you expect the total cost of the project to be?

[brainchild]

Epic Proportions, on Mar 4 2008, 11:12 AM, said:

What do you expect the total cost of the project to be?

For micRo, about $500-600 for the mechanics, and for RoGR, about $1000 (includes motors). You'll still need drivers which you can buy from us, elsewhere or make yourself. If you're handy with an iron, you can talk another micRo or RoGR owner into engraving your PCBs, allowing you to save about $300 over commercial drivers. You also need a computer. We're running our bot on a 6 year old "emachines AMD" that cost under $300 when new.

[joecnc2006]

I do not know your motor specs of the ones you are using or planning to use but Geckodrives.com are coming out with a new 4 axis driver which will be around 150 i think, they will have individual drivers for sale for 30.00 each, supose to be in production by end of this month, If you are into CNC already you know Geckodrives are the leaders in the most reliable drives, I run 4 g201's not on my 4x4 machine and works great.

Here are pictures of the completed drive, the smallest i have ever seen. in one picture you will see the new drive MB on the left and a g201 mb on the right (which i have are 2.5"x2.5" total)

specs are 50vdc, 3a drivers. (Called: G-250)

I will be buying a 4 axis system (Called: G-540) as soon as they have them finished and will test on my CNC 4x4 Hybrid machine.

It should run the RoBLOCKS with no problem at all, once again depending on the motors, and how they are wired, serial or parallel. (bi-polar only of course).

Driver board:

 IMG_1389_small.jpg (4.37K)
Number of downloads: 38
 IMG_1449_adjusted.jpg (7.25K)
Number of downloads: 36

Driver board comparison:

 G250_G201.jpg (3.78K)
Number of downloads: 21

And rendering of completed 4 axis driver system:

 G540.jpg (102.54K)
Number of downloads: 53


Joe

[brainchild]

joecnc2006, on Mar 4 2008, 05:04 PM, said:

I do not know your motor specs of the ones you are using or planning to use but Geckodrives.com are coming out with a new 4 axis driver which will be around 150 i think, they will have individual drivers for sale for 30.00 each, supose to be in production by end of this month, If you are into CNC already you know Geckodrives are the leaders in the most reliable drives, I run 4 g201's not on my 4x4 machine and works great.

Here are pictures of the completed drive, the smallest i have ever seen. in one picture you will see the new drive MB on the left and a g201 mb on the right (which i have are 2.5"x2.5" total)

specs are 50vdc, 3a drivers. (Called: G-250)

I will be buying a 4 axis system (Called: G-540) as soon as they have them finished and will test on my CNC 4x4 Hybrid machine.

It should run the RoBLOCKS with no problem at all, once again depending on the motors, and how they are wired, serial or parallel. (bi-polar only of course).

Joe

Very interesting. Gecko just keeps it coming...

[brainchild]

OK, RoGR Jr (now micRo) building RoGR.

Got to the shop today, found 100lbs of billet at the doorstep:

 billetbox.jpg (148.56K)
Number of downloads: 52

Sweet, new billet. God this stuff is huge. The NEMA 34 motor looks puny next to its 2" x 4" x 6" mounting blocks.

 RoGRBillet.jpg (111.81K)
Number of downloads: 61

Note that the router spindle in the pic is nearly 4" diameter...this metal is thick .

[brainchild]

RoGR builds RoGR #2:

Next was to machine a billet spindle holder for the big router...the little ones die too fast....This piece is machined out of 3/4" alum with a dying "hobby router":



A completed tool holder: The result is great:

 finished_tool_holder.jpg (137.25K)
Number of downloads: 46