Newbie here, with (some) electronics experience and light Arduino. I have a project in mind I can visualize but not determine the best approach with Arduino. Think X,Y, and Z axis. Using three linear actuators with stepper motors I need to move a payload up/down, back & forth, and laterally perpendicular to the back & forth. Kind of like a CNC machine?
So imagine you're lying down on your stomach and LA #1 moves a massage head vertically downward toward your back. LA #2 moves the head laterally across your back. LA #3 moves the head up and down your spine. That is the X, Y, Z axis I mentioned. Linear actuator #1 is mounted vertically. LA #2 is mounted to the carriage of #1 and moves horizontally. LA #3 is mounted to the carriage of #2 and also moves horizontally, but perpendicular to LA #2 (up & down the spine).
Ultimately I want to use a wireless control glove I have patented for something else, but for now even a joystick for proof-of-concept would be fine. I have one Linear Actuator (Open Builds C-Beam, love it!) and one Uno I'm playing with now but I don't really know.. will I actually need 3 Arduinos, 3 motor controllers, and 3 power supplies etc., to go with the 3 linear actuators? My goal is to have one AC power switch to activate the whole contraption, and one remote control device for complete X,Y,Z control of the head movement. Any help would be much appreciated! Again, Arduino newbie here, go easy on me please...
Well, 3 motor controllers for 3 motors seems wise, unless you get a multiaxis controller, they're quite common. One PS will power 3 motors if sized appropriately; for sanity, do NOT run the Arduino from the same power supply. One Arduino will do the whole job, if you select the right Arduino. Nano, probably not. ESP32 products, likely.
Please tell me you'll really think about safety on this one. I had a vision of a mechanical "hand" pressing my spine through my stomach into the table below... SQUISHY!
Thanks for the reply. I'd like to keep the hardware as minimalist as possible since the C-Beam actuators are already pretty hefty. I envision this as a structure that arises next to a mattress, a plain C-Beam as a post, topped with a loaded C-Beam as LA #1. Practicality is an issue, meaning I'd like it to maybe fold/disassemble easily, but for the prototype it just needs to work. I'll look into the multi-axis controller. As for PS, I presume the key value here is amps since the voltage would be the same, wired in parallel? meaning the PS needs to be rated high enough to cover the combined power draw? Any additional advice would be appreciated.
Safety: absolutely, I thought through the same nightmare- the unstoppable stepper motor from hell pushing my lumbar vertebrae into my navel. So much for pain relief! I'm designing the lowest stop position of the vertical actuator to be safely within 6 inches of the mattress top. That way, it couldn't physically go any further. The real beauty of this thing will be the percussive massage head that delivers a fantastic effect; the key being you control it yourself instead of telling the therapist to "go a little to the left- no, to the right, up just a little... ad nauseam" etc.
Actually, no. Only one axis would move at a time, though it would be nice to have good response time between them. (No lengthy delays.) So… having said that, maybe the power supply doesn’t have to be very hefty after all. As long as no two motors are going at the same time…
There may even have to be a fourth motor. I’d like the payload head to pivot, or swivel to provide for an off-angle approach on the sides of the spine. Only a strict 90° perpendicular approach to the spine is not good enough, it needs to roll off the edges on either side.
So I purchased an ESP32 module and am learning how to use that instead of the Arduino. Looks intriguing since I can use the Arduino IDE to program, but it's definitely more challenging. Anybody have any recommended YouTube or other help for getting three stepper motors to work with the ESP32 and TB6600 driver? Basically, either a joystick control environment, or three momentary switches, one for each motor. Perhaps, on each switch PUSH A triggers motion forward and PUSH B toggles it to reverse? Open to all suggestions! TIA.
Hi Tom,
Thanks for the advice, well taken. Here is the actuator, I have one so far; they're great, I really like the C-Beam design and solid craftsmanship:
I'm powering this first one singly for testing, just a simple regulated PS here:
I might get a bigger one for the three together but I don't foresee more than one motor running at a time so maybe it's not an issue.