Hello builders!

I wold like to use this build (1500mm with NEMA 23) in a research lab.
I have no experience with linear actuators, so could you please advise me if this design fulfils my requirements.

The idea is to mount a small monitor (or tablet) on the actuator’s plate and move it in
a cyclic patterns (constant speed, step displacement, sine displacement, …):



My questions:

1. Is this design rugged enough to handle max. 2kg load at max. speed 1m/s?
2. I would like to accelerate from 0m/s to 1m/s in shortest distance possible. What would be the distance? The same question for slowing down from 1m/s to 0m/s.
3. How precise would be the positioning of 2kg load? For example, moving it 1000 millimetres at max. speed 1 m/s.
4. What noise shell I expect from linear actuator with the bundled NEMA 23 (in dBA or description)?

Thank you for any advice!

 

Thank you for the reply. I suppose, it must be quite difficult to predict all the properties of the linear actuator in a specific use-case situation, but reading your answers, I think that it is worth to give it a try. If I finally build one, I will let you know the results. Thank you again.

 

Hi, I want to build exactly this v-slot nema 2 linear actuator belt driven, and can move from 0 to 40" or 60". I see the list of parts . In stepper motor, it shows "Note: Stepper motors require special driver circuits to drive them. These drive circuits allow you to step the motor precisely to any position.". Can you please let me know what stepper motor and drive I need to buy and anything else I need to buy to complete this project.
Qty Part Name Part Link Comments
4 Low Profile Screws - 25mm Low Profile Screws M5 (10 Pack) SKU 20 - Sold in Packs - You will need 4 Singles
6 Low Profile Screws - 8mm Low Profile Screws M5 (10 Pack) SKU 946 - Sold in Packs - You will need 4 Singles
2 Aluminum Spacer - 6mm http://openbuildspartstore.com/aluminum-spacers/ SKU 90
1 Aluminum Spacer - 3mm http://openbuildspartstore.com/aluminum-spacers/ SKU 175
3 Double Tee Nuts http://openbuildspartstore.com/double-tee-nut/ SKU 60
1 3GT (GT2-3M) Timing Pulley - 20 Tooth https://openbuildspartstore.com/3gt-timing-pulley-20-tooth/ SKU 830
2 Eccentric Spacers - 6mm http://openbuildspartstore.com/eccentric-spacer/ SKU 226
4 Delrin Solid V Wheel Kit http://openbuildspartstore.com/solid-v-wheel-kit/ SKU 480
1 Smooth Idler Pulley Kit http://openbuildspartstore.com/smooth-idler-pulley-wheel-... SKU 550
1 Idler Pulley Plate http://openbuildspartstore.com/idler-pulley-plate/ SKU 570
1 Motor Mount Plate for Nema 23 Stepper Motor https://openbuildspartstore.com/motor-mount-plate-nema-23... SKU 910
4 Cable Ties - 4" http://openbuildspartstore.com/cable-ties-10-pack/ SKU 675 - Sold in Packs - You will need 4 Singles
4 Low Profile Screws - 15mm https://openbuildspartstore.com/low-profile-screws-m5-10-... SKU 922
1 V-Slot Gantry Plate (20mm) http://openbuildspartstore.com/v-slot-gantry-plates/ SKU 935
1 3GT (GT2-3M) Timing Belt - By the Foot https://openbuildspartstore.com/3gt-gt2-3m-timing-belt-by... Length Varies - 3' for 250mm, 4' for 500mm, 7' for 1000mm, 11' for 1500mm
1 Nema 23 Stepper Motor https://openbuildspartstore.com/nema-23-stepper-motor/ SKU 518
1 V-Slot® Linear Rail http://openbuildspartstore.com/v-slot-linear-rail/ Varies
4 Nylon Insert Hex Locknut - M5 (10 Pack) https://openbuildspartstore.com/nylon-insert-hex-locknut-... SKU 10-pack

 

Hello, what would be the best way to mount a rotary encoder on the linear actuator? I have two reasons to do it:

1. To know the exact position of the plate/load, to make sure that the load is able to keep up with programmed acceleration, that there is no slipping of the belt, etc.
2. As a security measure: to detect if the plate/load is blocked (unable to move).

So, to mount the rotary encoder (I hope I can include the link):
https://www.amazon.com/Aideepen-Enc...e=UTF8&qid=1544313625&sr=8-5&keywords=encoder

I can think of a few options:

1. To mount it directly on the plate and use some kind of a wheel mounted on the encoder’s shaft to make it spin in contact with the V-slot rail.
2. To mount it on the V-slot rail (close to the motor), and put a 3GT (GT2-3M) Timing Pulley on the encoder's shaft to make it spin in contact with the belt.
3. To mount it on the V-slot rail and substitute a Smooth Idler Pulley with the rotary encoder.

Which option would be the most recommended? Are there any parts in openbuildspartstore to make the mount easy?
Thank you.

 

Hello Rick 2.0, thank you for the reply. I have not considered the dual shaft stepper mount because, I think, I should be watching the plate/load or at least the belt movement. I will be using the linear actuator in a way that differ from typical cnc use-case:

1. To move the load between 1kg and 2kg with maximum acceleration that the high torque stepper motor allows.
2. Try to control the trajectory (I mean acceleration and speed) of the load as precise as possible (to replicate programmed patterns). At least I have to know exact position of the load at every moment to take into account its real trajectory.

If I mount the encoder on the stepper’s shaft, I will not be able to detect the belt slipping (I do not know if it is real issue or just my imagination).

 

I am using a v-slot nema 23 1500mm linear actuator to run a powdercoat gun back and forth with a travel distance of about 1 meter. I purchased two of these actuators because I have two guns that need this movement.

I wanted to use the CNC xPRO controller to control both actuators. I thought I could hook up one actuator to the x-axis and one to the y-axis. Then I could use the OpenBuilds CAM to draw a diagonal line through the x and y axis, and thus would have matching movement in both actuators.

I basically wanted the actuators to run back and forth through this diagonal line continuously with a change in speed at one point. Also, I wanted one directional change on the diagonal line to be slower than the other.

I am having trouble getting this done in the software. Is it possible to do this sort of thing with CNC software?

 

Hi Rick 2.0, thank you for the suggestion but I have a difficulty to visualize your solution. Do you mean to replace the original Iddler Pulley Plate (and Smooth Idler Pulley) with the modified one that you suggest? If it is not too much to ask, could you please sketch it (by hand on a piece of paper or whatever) to get a better idea? Thank you a lot.

 

Rick 2.0, thank you very much, now it is clear for me.

 

I messed around with the G code, but wasn't able to find a way to program a loop with grbl. I need the linear actuators to run back and forth, until the powder coating job is complete. Will I have to program the xPro with arduino, or is there something I am missing?

 

Sorry for my ignorance on coding. When I hit the start button, I basically need the linear actuator to run back and forth continuously (maybe for 6 hours or so) until I hit the stop button. I looked up the g code supported on grbl and couldn't find a command which would allow movement to repeat continuously until I pressed stop. Of course, I might be mistaken.

 

Hi All!

I’m in the starting phases of a project where I need to move approximately 5kg of weight over 300mm with speeds upwards of 600mm.

I intend to drive this with the ODrive, which is basically a powerful hobby motor with an encoder on it, I figure this should give me the power and speed needed.
However, I have concerns that the belt would slip due to weight and resistance. Should I be looking at leadscrews (according to my calculations there would be too much whip in them at these speeds and distances)?

 

600mm/s sorry! Forgot the unit!

 

This question is about motor selection for the V-Slot NEMA 23 Linear Actuator (Belt Driven) and about accuracy with load mouted on the plate.

Does it make any sense to use the high torque (345 oz*in) NEMA 23 motor instead of the standard NEMA 23 (175 oz*in)?

I am asking this question because:

1. V-Slot NEMA 23 Linear Actuator (Belt Driven) specification says:
   • Max Force: 7.5lb (33N).
2. The Actuator Test Specs specifies:
   • Result: Belt skips at approximately 7.5lb (33N)

If the result was that the motor stalls at 33N I could obtain more force by using stronger motor, but it says “belt skips”.

The actuator uses 3GT (GT2-3M) Timing Pulley with diameter 18.3mm, so the standard NEMA 23 motor (175 oz*in = 1.24Nm) can produce F = 1240 / (18.3 / 2) = 135.5N. This force is much higher than 33N when the belt skips, so using stronger motor makes no sense to me.

Maybe, if I wanted to control the motor at high speed the additional torque would be advantageous.

Are my conclusions correct?
Is there any way to prevent the belt skipping?

What accuracy shell I expect with 1kg load mounted on the plate and moving it between 0 and 1000mm?

In the document Actuator Test Specs, page 3, test 4, target distance 60mm was measured 61.17mm (max error 1.17mm) without load. So, what positioning accuracy (max error) shell I expect with 1kg load and travel distance between 0 and 1000mm (at slow and high speeds)?

Thank you.

 

Sorry for the late reply, but I'm not really involved with open builds any more. You are right that the stronger motor with the belt drive doesn't make much sense. The limitation is in the size of belt and pulleys. A 5mm pitch belt would be much better, but this is not really supported by open builds. If you are concerned about the belt skipping, consider using a screw instead. All of the testing was done under no load conditions, so I can't comment on your specific scenario with a 1kg mass. That doesn't seem too high, but if you are trying to move really fast, the belt will be a limiting factor.

 

Rob, thank you for the reply.

 

I just received my kit and have a cheap amazon stepper motor controller that I'll be using till I work out more details. I was wondering is there is an Arduino project out there already for linear actuator or something similar? Thanks!

 

Thank you Giarc! I'll be checking this out!

 

Hoping this is the right place to ask this question. I built this project with the NEMA 23. All my other motor are NEMA 17s from Steppermotor online and are wired Blue|Red|Green|Black. The pre-wired terminal block included (which is very nice indeed, and I'm replacing my current build with these) is Red|Blue|Green|Yellow. I'm wondering if I ignore that order and go with what I'm doing when hooking it up to my stepper drivers which are TB6600's? TIA