The flange that they take out near the beginning looks like it couldve been a rotary optical encoder, but there is one clearly later on as well (the see through disk with one dash that feeds through the brown underbelly component of the IC). Anybody able to clarify what the difference is for me between those two components?
Yes correct there are two encoders. The one I took out first is connected to the output of the Gearbox and the second one is connected to the input. The one connected to the input keeps track of the motor Position. The one connected to the output should be an absolute type encoder. I guess this enables the robot to know the position of the axis right after startup and eliminates the need for homing the robot.
So there are two concentric axis in the middle ? one for holding the Rotor - the outer one. And one holdeing the output shaft (probaply for stability reasons of the output) and transmitting the outputshaft rotation to the encoder in the back? You have been able to rotate the rotor after removeing the Outputshaft
very nice job. pls, let me know if Im on correct way. These motor is a BLDC with a torque sensor , one encoder and an harmonic drive???. obviously with its power electronics based in a DSP and mosfets to boost the motor. thank you.
If the encoder is optical by way of that glass disk and the pcb mounted read head, then what is the first item you removed that has the freely rotating centre? I assumed at first that was the encoder. Unless it has two?
Thanks for the tear down! Question 1 at minute 3:25 a rotatory sensor is removed. What type of sensor is that? Is that for tracking absolute rotation? is it a torque sensor? Question2 at minute 5:50 there is a Fence on the optical encoder and it has a linear actuator to press down a plunger. What is that for? Does it limit the orientation uncertainy at startup?
I am happy you enjoyed the video. About question 1: That ist most likely an encoder to track the position of the output side of the gearbox. Together with the second encoder which tracks the input/motor shaft rotation. It can be used to find the robots position after a restart without having to move the robot into an endstop to home its position. And about question 2: The litle pin is acting as a sort of brake. In its resting position it is blocking the star shaped piece which is connected to the motor shaft. When actiated the pin is pressed down and out of the way so the motor can spin freely. This can be used to prevent the robot from moving when it is turned of which is nessesary because the strain wave gearboxes are backdrivable. It can also be used as an emergency brake. I also want to say that I cant be sure about any of these things because I am not a professional about universal robots.
After watch your video you give me enthusiasm to try to do maintenence to my mount but before do it want to ask you if we need take care of pieces locations, it means I saw you put the mount on aling position so to re-assembly can please give us the steps to make it in the proper way. Thank you
Heey hey, Thanks for the video. Quick question, what type of grease /lube do you use? I hear very conflicting stories on using white lithium grease. Some day it is the best others say it will ruin your mount.
I'm afraid I don't have a clear and simple answer for your question. But I am happy to share my experience. For my mount I have used a muli purpose grease 1 from Würth because I had it laying around. That's not the best possible grease but it worked fine for my old LXD75 mount. Lithium grease offers very good performance but it can be aggressive to some Polymer's like Nylon for example. A lot of people seem to be happy with using Super Lube on their mounts. But I have no experience with that. Soon I want to hypertune my Celestron CGEM mount. For that I will try some grease with MoS2 which works similar to graphite. (Something like Liqui Moly LM47 grease) but I haven't tried it yet.
Nyogel dampening grease - 765c and 767a (the latter is stickier). They are very high quality and not cheap. Lithium grease will separate over time and is not the best for cast aluminum. It might be fine for the worms, but I use Nyogel.
Pretty shure they use U.S Digital optical encoder on the motor side, can't exactly tell what the output side is. But definitly hast to ba a magnetic one, maybe something like a RLS AksIM-2.
@@jonashdjg1345 Do you mean that the lower optical encoder is on the motor rotor and the shaft encoder which is removed first in the video is a second encoder that is connected to the motor output via a shaft in the centre? I was wondering what that was. I am currently designing something with an RLS AksIM-2 and they supply the read head and the codewheel separately, whereas the unit seen here looks like an all in one type encoder product. It also looks like it senses in the radial direction around the outside of the shaft rather than reading a codewheel in the axial direction. Mysterious. either way, fascinating video.
@@hoarp001Its also possible that they use one frome a different manufacturer but for me it looks like they have just designed a case and a small shaft for the Aksim. But the Blue pcb irritates me, maybe it could also just be a completly costum encoder they build. They use a incremental encoder on the Motor and an absolute on the output shaft (after harmonic drive). Im pretty shure that they do that for one the absolute Encoder only rotates 360° and directly measures output shaft angle and second, with two encoderes they can quickly discover torque spikes for their collision detection with humans.
