40$ SCARA Arm

cults3d

This SCARA robotic arm makes a fantastic base for programming projects, and the best part is it only costs less than $40. While the strength it can support isn't extremely high, I made do with what I had on hand by choosing certain materials that were readily available to me. I opted for reed sensors and 3$ stepper motors because they fit my needs perfectly. The top plate, titled "top.stl," is suitable for both a stepper and a 360 servo to handle Z movement. If you're using a servo, be sure to print the rev counter (“rev_counter.stl”) as well, and mount an extra magnet and an extra reed sensor in place. However, if you use a stepper, all you'll need is an extra coupler for it to work smoothly. For ease of programming, I highly recommend going with the second solution – it's also simpler to program. I've left a thread hole at the end of the arm so that you can design your own modules and share them with the community. For optimal performance, I advise converting the steppers to bipolar function, which will give them more torque and allow them to work directly with the Arduino RepRap and CNC boards. To make this happen, simply follow this tutorial: https://www.youtube.com/watch?v=sY1Y_BJ-fTQ . Unfortunately, I didn't write any demo program because, honestly, programming isn't my cup of tea. If you like this model and want to see it in action, please take the time to write some lines and share your code with me. I'd love to see what you come up with! Feel free to leave a comment if you have any questions – I'll respond as soon as possible. If there are many of you who need help with the assembling process, I might even create a video tutorial for it. Here's what you'll need: - 3 x 8mm steel bars (pick your desired length) - 1 x M6 threaded bar - 6 x M6 nuts - 12 x M4 nuts - 2 x M4 25mm screws - 9 x M4 20mm screws - 34 x 8mm steel balls (http://www.dx.com/p/8mm-carbon-steel-slingshot-ball-silver-47-pcs-258609) - 2 x M3 plastic screws - 1 x M4 50mm screw - 2 x 22mm bearing (http://www.dx.com/p/ec-hbcs-7-high-carbon-steel-skateboard-bearings-set-silver-8pcs-428675) - 6 x 8mm linear bearing (http://www.dx.com/p/n-linear-ball-bearings-silver-10-pcs-468551) - 1 x 7mm x 20mm spring - 1 x button (http://www.dx.com/p/plastic-copper-push-button-power-switches-red-10-pcs-153209) - 1 x micro bearing (http://www.dx.com/p/rc-axial-1-10-scx10-jeep-wrangler-bearing-5-x-11-x-4mm-10p-418705) Choose from one of two configurations: Configuration 1: - 3 reed sensors (http://www.dx.com/p/mini-arduino-magnetic-detection-sensor-module-black-135504) - 3 x 6mm magnets (http://www.dx.com/p/d12-6mm-cylindrical-strong-ndfeb-magnet-silver-20-pcs-450996) - 2 stepper motors (http://www.dx.com/p/28ybt-48-dc-5v-stepper-motor-uln2003-driver-447220) - 1 x 360 servo motor (http://www.dx.com/p/360-degree-rotary-steering-engine-black-121328) Configuration 2: - 2 reed sensors (http://www.dx.com/p/mini-arduino-magnetic-detection-sensor-module-black-135504) - 2 magnets (http://www.dx.com/p/d12-6mm-cylindrical-strong-ndfeb-magnet-silver-20-pcs-450996) - 3 stepper motors (http://www.dx.com/p/28ybt-48-dc-5v-stepper-motor-uln2003-driver-447220) - 1 x coupler (http://www.dx.com/p/winding-thread-elastic-top-wire-coupling-aperture-10-x-10mm-silver-467421)