[HELP] Firgelli Linear Actuator

aficionado · Joined: 14 Mar 2011 Posts: 5

Hi

I am planning to use a L12-100-210-6-P firgelli linear actuator for my educational project. Since I am not good enough in electronics, there are a few questions which I need help.

Can anyone help in a more straight forward explanation by what it means of P version (position feedback signal)? I mean, can I simply control the moveable rod position by a potentiometer?

Does anyone know what kind of material the rod is (stainless steel, aluminum, etc)? Because I want to engrave it so that I can put scales (in mm) on it to measure its traveling distance.

Many thanks for your help Very Happy

temtronic · Posted: Mon Mar 14, 2011 6:21 am

Simply , yes.
According to the datasheet, the wiper of the pot follows the travel of the shaft.You'll have to make some electronics between the pot and the PIC though.Specs say pot is 2.75K / mm x 100 mm travel = 275k. Some sort of opamp buffer will do.Also the ends of the pot are available and typically one end goes to ground, the other to a STABLE reference. That way you'll have good,accurate readings all the time.Be sure to add caps as required to filter out any noise.

I'd setup a stable Vref of 5 volts, use it for both PIC ADC Vref as well as the pot, using 10 bit adc, you'll get .1mm / bit....

Most shafts will be stainless steel, easy to email the mfr. to confirm. I would NOT mark the shaft at all, it will damage the seals, possibly allowing 'bad stuff' inside destroying the pot and other electronics !
Instead mount a small 'flag' or 'pointer' onto the end of the rod to move next to a section of metric tapemeasure.

The RC plane guys must be happy ! With the rc servo option, these would be ideal for landing gear installations, getting rid of the older onboard air reservoir systems !

John P · Joined: 17 Sep 2003 Posts: 331

However, if you run your pot between Vcc and Gnd and also have a buffer amplifier that runs off the same power supply, you are likely to have difficulty reading the ends of the travel accurately. You'd need to use a wider power supply range for the amplifier, or you could put additional fixed resistors in series with the pot so that the output voltage never reaches Vcc or Gnd.

Humberto · Posted: Mon Mar 14, 2011 7:18 am

aficionado · Joined: 14 Mar 2011 Posts: 5

Thanks a lot guys...but...I am not so much into electronics..so I can hardly understand what you all are saying..sorry for that..

Let me tell you what I understand (maybe I am wrong, correct me).
There are 5 connections for L12-P actuator, namely 1 to 5 (as in the datasheet). I simply thought that I can connect 3 and 4 to power supply, and 1, 2 and 5 to a simple potentiometer and that's it..I can control it just by twisting the potentiometer, no need for other electronic devices such as PIC, ADC, op amp or anything else. Is that so? Please guys..correct me if I am wrong..

Ok now, if I do need some electronics, I am not sure I can build it. I may consider buying the control board. But the problem is there are more than one boards (this is what I know), i.e. CIB and LAC. What board is actually suitable for L12-P? And does anyone know the price? One more thing, can the control board show the distance traveled by the rod?

Your help are very much appreciated.

Ttelmah · Joined: 11 Mar 2010 Posts: 19496

It depends on the L12 version.
The more basic ones require external control electronics. The ones with numbers like:

L12-SS-GG-VV-I-L

With 'I' in the penultimate position, have the control electronics built in, and can do what you want.
These though have a _six_ wire connector, not five. The ones with the five wire connector, need an external controller. Page 3 of the L12 data sheet, 'Option I', '0-5v Interface mode'.

Best Wishes

Ttelmah · Joined: 11 Mar 2010 Posts: 19496

On 'reading the position', this would depend on the scaling you want, but simplest, if you attach a voltmeter to the voltage on the feedback pin, then this would read 0-5, for the movement of the shaft. Add scaling resistors, and this could show 0-1, --2, etc..

The CIB, was the older control board. The LAC is the newer one. Both would do what you want, the LAC, adds USB interfacing, while the CIB had serial. However both can act as potentiometer to position controllers without using this interface.

Best Wishes

aficionado · Joined: 14 Mar 2011 Posts: 5

Ok, thanks for the info. I think it's better if I briefly describe what I want and seek some help and opinion from you guys.

I want a moveable rod (vertically), which can be moved and stopped anywhere from 0-50mm, and I have to know the exact location/distance when it stops (I can't see the rod. It will be in a closed box with only wires going out).

So what are the options I have? Should I have a control board with the L12 motor? What kind of L12 motor I should have (P or I)?

Many thanks guys. Really appreciate it.

necati · Joined: 12 Sep 2003 Posts: 37 Location: istanbul

http://www.servomagazine.com/media-files/797/PQ-CIB_controller.zip

aficionado · Joined: 14 Mar 2011 Posts: 5

Geps · Joined: 05 Jul 2010 Posts: 129

Ttelmah · Joined: 11 Mar 2010 Posts: 19496

Seriously, anyone in our company who downloaded a .ZIP file without knowing what it was, would probably find themselves out of a job....

It was silly, to post the link, without a basic 'what this is' explanation.
However though 'great', given the original poster's lack of knowledge, I'd doubt if they'd be able to use this without a lot of help.

Best Wishes

Geps · Joined: 05 Jul 2010 Posts: 129

aficionado · Joined: 14 Mar 2011 Posts: 5

ep7000 · Joined: 25 Mar 2011 Posts: 1 Location: usa

Yes I'm new here. Here is a place to get actuators, straightforward, no BS.
http://www.linaractuator12v.com

Hope it helps.

Peace!

ep
_________________
Linear Actuators 12v