The video shows the settings in the Excel file for 11 teeth. Depending on the size of your wheel, make sure the holes for the inner shafts and central shaft are not too big, and it should work
9:42 20kg at this angle are not 20kg perpendicular to the output axis, so either you need to calculate the torque with a shorter distance between motor axis and mount point of the spring
Very nicely explained. Thank you for this video. I would like to learn more about this design. Is there a technical term for this actuator design? What terms can I use to search on Google? Thanks in advance!
It is a very nice idea to use ball screws in all three joints but do you thing will you be able to fit this design in a quadruped chassis? It looks very big and not soo compact.
Yes they are a bit long, but they can fit in a 0.8 - 1.0 meter quadruped. I am trying to shorten them by avoiding the motor shaft coupling. Yo can see this in my next video. Thanks!
You make amazing content. Thank you. I wouldn't use the same approach. Ball-screw mechanism takes too much space and heavy. I would use ballscrew only on one joint, and would use harmonic/cycloidal reduction on other two joints.
Very nice! The cycloids look durable, but I think the mounting of the motor should be better. Only those 4 bolts on the housing keep everything in place. That would also help with positioning the motor for coaxiality. Great work, subscribed!
I really like your designs. Have you considered removing the knee and using the linear motion directly to change the hip-ankle length? The may reduce your maximum torque requirements by removing the bent knee geometry.
Do you mean something like a telescopic leg? I think that would be extremely strong but very slow too (at least with the motors I am using), and in a quadruped you need to be fast. Note that the shank crank is 26mm, and the shank is 260 mm, then we are multiplying speed by 10 (and dividing force by 10 too). Maybe with a motor with a very high Kv (1700 Kv for instance) what you propose could be feasible... I will give it a thought!
Yes,I was thinking telescopic. You can get different ratios of rotation to screw-length which might help, although I'm not sure of the weight/size trade-offs.
you dont even need PEEK, some of the nylons would be sufficient, and also printable on a bambu x1c. 3dxtech has a MoS2 infused nylon that i like a lot and intend to do this with, called WearX.
Fun project! but two things really grinds my gears. First of you used no lubrication at all, and secondly you use the heads of bolts as the transfer from the motor and the gearbox witch is a bold move to say the least.
To improve accuracy, how about getting the holes cut slightly smaller, then using a reamer to ream out the holes to final dimensions? Also, using shoulder bolts instead of using all thread bolts?
