Thank you. This is an excellent and well thought project. Can you please make us a short menu illustrating how you actually made the Box joints in Fusion360 with the App. I installed it but cannot get it to join. It will be greatly appreciated.
It would be good to have a comparison for the sake of efficiency. (I assume this is less efficient than cycloidal drive?) Do you have another video with a torque test on an equivalent cycloidal gearbox? I just checked your 20:1 video, and 1.6 is much kess than I expected, assuming the same stepper. I suspect that this is more efficient when compared to a standard one without bearings, but a standard one with bearings would be a cool comparison. As well, a version like this but with say 3-4 bearing steps around the 1t gear instead of a continuous profile might reach a higher efficiency than this.
Totally brilliant explanation of how this gear can be derived geometrically from a normal cycloidal gearbox. The concept has of course been known for a long time, for example from a recent Bosch patent. But the idea is probably many decades older.
I printed everything without a hassle. Thank you for sharing the fusion file as well. Could squeeze in a servo I had laying around. In love the simplicity of the rear axle. You pushed my creativity on making small RCs. Thank you so much!
I disagree with characterizing this as any sort of cycloidal drive. A cycloidal drive works by pushing a bearing into an angled surface, producing torque by rolling downhill in a circle. This video uses the geometries of cycloidal drive gears, but it rotates a circle against a gear. It is basically a 1-tooth pinion gear. It does not „roll downhill“ anywhere. In a cycloidal gear, the force pushing the cycloidal gear parts apart at the sliding surface is converted with high efficiency to torque. In this gear arrangement, similar separating forces are present, but because of no rolling on the sliding surface, they are lost to friction. I suspect that if you where to make a custom involute gear with 1 tooth as a helical pinion gear, it would work better than this.
Now put 3 (or 4) of the internal gears 120 (or 90) degrees apart and put large planetary gears on the end with a small sun gear. Probably not too practical since another set of gears will introduce backlash, but there's still internal space that could be used to increase the gear ratio.
Where are the STLs. I have a 4 dof arm, but I like your design using double cycloid gears. I have all the parts already (surplus from other projects), but no 3D files.
Absolutely fantastic work! I'm so grateful for your willingness to share this. I'll be sure to include you in the acknowledgements of my work and give you a glowing recommendation.
This is an excellent video. I built the HowToMechatronics SCARA robot arm (4 DOF), using 4 stepper motors and one servo motor.(for end effector). The designer also provided a GUI made with Processing language. The entire robot uses an Arduino UNO. The build went well and everything works, but now the fun part of teaching the robot arm to do stuff. The GUI shows forward and inverse kinematics and I'm trying to develop a system for teaching it to pick up wood blocks to spell a name. Your video certainly helped explain the Inverse Kinematics. Mechatronics worked out all the equations for the user, but didn't really describe how to use either to move the arm where the user wants it. (I can jog to a position and save the value, so I'm assuming this does the trick. The video was very well explained and you are very articulate. And you pronounced phi as "feye", not "fee" as some do. Small things matter.
Hi, Please help us to answer a few questions in regards to this video: 1: What is the main concept discussed in the video? A. Forward Kinematics B. Inverse Kinematics C. Robot Arm Design D. Trigonometry Basics 2: Which mathematical concept is used to calculate the angles for the robot arm? A. Calculus B. Algebra C. Trigonometry D. Geometry 3: What is the angle that determines the rotation of the base of the robot arm? A. Phi B. Theta C. A1 D. A2 4: What does the cosine of theta represent in the calculations? A. Hypotenuse B. Adjacent C. Opposite D. Sine 5: What determines the length of the arm in the calculations? A. Z B. L C. H D. Phi 6: What is the formula used to calculate the angle for the base rotation? A. Tan(angle) = Opposite/Adjacent B. Sin(angle) = Opposite/Hypotenuse C. Cos(angle) = Adjacent/Hypotenuse D. Cot(angle) = Adjacent/Opposite 7: What is the purpose of transforming angles phi and theta into angles a1 and a2? A. To confuse the calculations B. To simplify the calculations C. To complicate the arm movement D. To introduce errors 8: Which axis is considered when defining the new plane for arm movement? A. X B. Y C. Z D. L 9: What determines the angle a2 for the second arm in the calculations? A. Phi B. Theta C. A1 D. A2 10: What is the final step after calculating the angles a1 and a2 for the arm movement? A. Implement the code for robot arm movement B. Repeat the calculations C. Ignore the angles D. Change the robot arm design
Sorry to have to ask, but am I stupid? I have now spent what feels like hours reworking the files from Github in Lightburn. Could it be that the part of the cover with the 2 finger joints is missing? Cutting the files simply twice won't work out. Does anyone else have the same issue or just me? I really like the approach of using a machine to improve the same machine. It has a bit of a pre-apocalyptic Skynet flair to it
A very cool project. You brushed over the python code part, are you able to expand on this and show us how you did it. I understand the arduino stuff as working on my own camera slider. The internal gear within the base on one of your other videos looks very interesting and may reduce some print time in my project. I will have to rewatch that video and see if you have released the files for that strange gear, as you say its just interesting to watch. Just Sub to your channel
Great project! I've emailed you regarding licensing of the Github project. Currently, without any open source license, Github default license applies, which means no one has rights to download or use the source code and I guess 3D files (only view it on Github). Hoping that you can add a license. Thanks.
This is a fine video and a fine project. Well done. Thank you for sharing the f3d files. Unfortunately, many of us do not have Fusion 360 at the ready. Its wonderful, but expensive and complex. I have to assume that someone has produced svg files for this project. Many of the commenter have asked for such. Can you help us get svg files so we can make a bunch of these?
The cycloid gear looks to have a lot of wear surface making a plastic version have a short lifespan. I wonder if somehow you could use ball bearings in there, so the balls rotate as the friction surface, like how a ball screw works.
Hello. I’ve just come across your video and I loved it. I haven’t used my laser yet due to not having an enclosure and I’d love to build one like this. Do you have a file I could use please? I use lightburn. Thank you very much.
