Arduinos and Microcontrollers ref: Rotary Table Mew 249

Dave, the bench is certainly acting as a sounding board but it is still loud even if I pick it up. No spare power supply but I have a feeling it may work better with 24v. What I find really odd is the change in tone half way through a step. It sounds fine if I just set it to run though. Confused

Thanks for the link.

John

Edited By Journeyman on 19/02/2017 18:11:54

Thanks Carl, I will bolt it to the mill later and see what it sounds like then. I need to try some test machining with it anyway so a dual purpose run. I know stepper motors make all sorts of weird noises but I still think this is too loud.

John

Carl, I have never used a stepper motor before so I have nothing to compare with other than CNC videos on the web. Possibly a bit old school on my behalf - "if it sounds right it's probably OK, if it sounds rough there could be something amiss!" I will give it a shake down cruise and report back.

John

If you activate micro-step[ping in software and on the board, it will probably be quieter (or at least more musical) but it may have less torque.

Neil

It's a real shame that quite a few people have come up with an Arduino based rotary table project but have copied one another in that they just use the shield for input.

There are very, cheap keypads made for the Arduino costing about £1.50 each and there are also pre written sketches for them but no one thinks it important enough to link the 3 parts together to give a direct input like the Division Master or Steve Wards very well though out controller.

Instead they rely of 5 buttons to produce layer upon layer of nested menus and for what ? To save £1.50 ?

Neil, tried micro-stepping makes it slower but not much quieter.

John, knowing very little about Arduinos or programming made this a useful first project. Menus aren't too bad select mode on one switch and then feed in number of steps. Agreed if you needed to set large number of steps or high angle this would take time but anything I am likely to do in the near future will be something like 6 steps or 60deg.

Set it up on the mill. Is a bit quieter but the main thing is it works spot on. Put a bar offcut in the chuck set it for 6 divisions and drilled 6 holes. Then went round again and the drill re-entered the hole exactly. Set it to 60deg and went round again and the drill lined up exactly. Then tried 7 divisions and was surprised that everything worked exactly the second time round as 360 does not divide by 7 exactly.  Box gets slightly warm after an hour messing about but nothing untoward. Well pleased and will now call it a day, awaits to be used in earnest.

John

Edited By Journeyman on 21/02/2017 10:32:50

Edited By Journeyman on 21/02/2017 10:34:04

My thoughts exactly, I have are Steve Wards controller very easy to make, the software works. Why reinvent the wheel?

John,

The whole point of the article was to show those with little or no electronics knowledge that systems such as the one covered are within anyone's grasp. It was intended to demonstrate that electronics and microcontrollers definitely have a place within the sphere of mechanical engineering, as they now have had in the real world for over 30 years.

I hoped to show that anyone can use these modular systems to assemble a device in short order that can solve a production engineering problem as it arises.

If I saved £1.50 in the process, so much the better.

Carl.

Carl,
​The article has made me go and buy one of these to play with, and I will be fitting it to my rotary table. I have also started looking at a couple of alternatives:-

1. Using a display using the i2c bus to reduce output pins, this may be slower to drive though, I need to investigate further.
2. Using a rotary controller as an input device instead of up/down buttons, not sure if it will make it any better than a full keypad though.

​I am also considering using this as the basis for a power feed on my mill, may not be the cheapest solution but may be useful for repetitive work such as gutting gears.

So from me a big thank you for the article and providing inspiration.

Baldric

My Steve Ward style Division Controller cost me under £5.00 for the board and associated electronics, including the LCD, I chose to use 12mm tactile switches and covers (for a cost of £0.48 for 12 of each).

I did also buy some Chinese keypads (2 for £0.99) but chose not to use them. If I had, I could have used a much smaller/cheaper perfboard as I would not have needed all of the space on the board for the button layout.

My stepper driver was about £5.00 and good for 2.3A, the PSU was free (old laptop PSU) and a DC-DC Buck converter for £0.87.

So the controller electronics cost me less than the cost of an LCD shield or even a clone Arduino, and it was not exactly a complicated layout - if I had gone with a Chinese keypad, the kit of parts would have been a board, a PIC microcontroller, some pin headers, an LCD, a keypad, 8 resistors and about 20 wires.

OK I had to buy a PicKit 3 and a ZIF adapter to program the microcontroller (about £8.50 for the pair), but these can be used on any other PIC projects I may have in the future (unlike dedicating an Arduino to a project - I prefer buying the Atmel chips and programming these with a cheap reusable programmer as well).

I applaud anyone who comes up with a new project for others to make use of, likewise using off the shelf items, but for ease of use and overall cost the Steve Ward one is hard to beat.

I rather agree with JS on the subject of nested menus. They're a way of controlling a lot of functions with a few buttons, and that can be confusing, or even completely opaque. I have equipment where it's impossible to access the deeper functions without a manual.

Gary Liming's Rotary Table menu system is fairly clear, but I think I could improve on it if there's sufficient interest. I can suggest three ways input might be simplified, without changing the display, or requiring too much new hardware.

One, with a 4x4 keypad, thus:

Cheap waterproof keyboards are readily available; the main problem would be applying the labels. Anyone know how to print on plastic or rubber sheet to make an overlay?

Two, with a rotary digital encoder and a panel mounted joystick. The mode would be dialled up by turning the Mode switch. Then up, down, right, left and 'go' would be selected by moving and pressing the joystick. Labelling is easy and the switches could be protected inside a box.

Three, with a Remote Control like this one:

I'm not happy with the remote method: it's expensive, has excess buttons, I would lose the stupid thing, and I don't like the idea of controlling machinery with with a remote that might get sat on!

Before I go mad hacking Gary's code, does anyone have an interest in having another interface? If so, is there a preferred solution? I don't have an example of a real one to copy and my ideas about the ergonomics of rotary table control are entirely amateur.

Cheers,

Dave

Like the idea of a mill power feed using a stepper. I have started measuring up my little WM14 to fit a motor on the end without a handle already! I await a suitable article in MEW...

John

John S,

Have you got a link please to the £1-50 keypad for the Arduino, i've seen keypads but not certain they can be used with the Arduino.

Emgee

Hmm...

My GOTO scope controller has many complex menus and entry screens all done with five buttons.

Entering an RA & DEC in the format HH:MMS DDD:MMS takes ages (compared to just a number of holes!) so adding a numeric keypad is definitely on the to-do list.

Neil

Love the [in]appropriate smiley things, Neil

MichaelG.