It's hard to beat a harmonic drive for a compact deep reduction drive. For all their issues, we still use them... and that says a lot. They're a far more economical solution to cycloidal drives.
Soon, i imagine we'll be looking at gears and toothed mechanical apparatuses like we look at horses and buggies today. Magnetic power is even greater, once its harnessed appropriately.
I subscribed because you talk slow enough for someone to follow what you are saying and you leave the video on what you are showing long enough for the viewer to follow it.
A possibly belated, but no less heartfelt and sincere thanks for taking the time and effort of making this absolutely EXCELLENT video. Explaining a complex subject matter in a VERY clear concise and approachable manner. It is in my opinion "pearls" like this video that makes Y.T. worth while. Best regards.
It is frustrating because there is nowhere I can request a refund. So seems money is just lost because Ian doesn't monitor his emails or phone calls. This is poor business management on what could have been a great product! Extremely disappointed with Ian on this.
Do not buy from Jetpack academy !!! Waiting since May no response to emails or phone calls. I have paid for the first lesson, they have taken my money but not provided the course material !! Its a scam !!
Do not buy from Jetpack academy !!! Waiting since May no response to emails or phone calls. I have paid for the first lesson, they have taken my money but not provided the course material !! Its a scam !!
They are starting to be used in astrophotography-mounts, that’s how I got interested in the topic. No backlash is the magic that‘s so important in this area. Great explanation, that’s why they are so,expensive
so uh Why not use two gears freewheeling where the lobes would be on the internal cam instead of a flexspine? you would still have the wedge-driving action, but it wouldn't require whatever process is needed to make a flex spline. I bet you could even install the inner gear bearings into slots axial to the "lobes" of the "cam" and spring load the gears to push away from the center so that you compensate for wear overtime and don't develop backlash. It'd be kind of like a planetary gear set, so I'm calling this a binary sun gear set until someone tells me it already exists xD
This is the most amazing and useful video i have seen in a long time. Thank you for explaining this. I was really struggling to understand exactly how it works. You are an awesome teacher.
Hello Sir, I hope you are doing well. Please let me know if you are using FOC and PVM for control? Of it is a different control technique? Are you using back emf for sensing?
Wow, you're a great teacher, your video is terrific and I now know something completely new about gear drives. Years ago I got a fanuc welding robot arm and was amazed at the zero backlash on the joints but never knew why it was possible until now. As for how to get 2 more teeth with the same pitch, it's hits me now that the outer ring is naturally LONGER than the inner one, hence can have 2 more teeth in its' path. However, sizing up the tooth depth to accomodate the mating, etc is a challenge.Thanks for this explanation and I'll look at more of your videos in the future.
At the 1 minute mark , lunar rover, notice the pilot doesn't move, at all, he is utterly frozen in position, head does not swivel to look left into the turn, arms and hand positions utterly frozen in place over all bumps, rooster tail dust from wheels in a vacuum seems very out of place, rate of wheel dust collapse to the ground seems incredibly fast for 1/6 gravity conditions and rover cart seems to have no suspension give at any wheel - maybe a tad but not much if at all, and the antenna doesn't wiggle except at the end of the clip at the strongest bump ... just my observations ... anyway eager here to learn about harmonic drives!
Super great explanation. One would think that the flex spline gear would fatigue over a short time, but they're so widely used in so many applications that it must not be an issue. Thanks for the great video demonstration!
Thanks for the concise explanation. I can see that these drives have multiple applications beyond the world of robotics. As an astrophotographer who deals with backlash on a seasonal basis (ambient temperature variations) this technology would be exceptionally well suited to telescope drives. My impression is that this type of mechanism would be less prone to backlash due to temperature variation. Chhers!
This is not a harmonic drive; It is a differential gear system, related to the split-ring planetary drive. In a true harmonic drive, the 2 high-torque members are the outer internal gear, & the flexspline, which is coupled to a cylinder terminated at its far end with a "bottom", forming a cup structure. There is no second internal gear. The bottom of the cup is the output & the outer gear is the stationary frame. The input is the wave driver. The outer gear & flexspline can be interchanged (output & stationary parts switched).
“Harmonic Drives” piqued my interest, but the differential drive ( e.g; windlass, boat hoist… ) is at least centuries old. I have one for heavy moving, mostly engine swapping, and probably older than me. The only confusing parts are your use of “complicated”, the new name, and the addition of poor engineering to this time-proven device.
