• Mats Önnerby posted an update 3 years, 4 months ago

    I have made new servo pulleys for the hand. They have two tracks with different diameters, since you need to pull a longer distance to close the hand than to open it.http://www.thingiverse.com/thing:1074604

    • This looks interesting – How would you describe the improvment to the hand’s movement?

      • To close one finger you need to pull 27mm but to open it again only 17mm, The 10mm in difference will result in that the lines easily fall out of the tracks, The servos will also have a deadband of 10mm before they start to pull, With this construction the lines will be stretched all the time, so the fingers will keep their position better.

    • The reason I am asking is if you think the springs that were introduced to keep the strings tight would still be needed ?

      • Good question. I don’t think that springs are necessary, but if you turn the wrist, the lines will be tightened. So you have to compensate for that by relaxing the tension on the lines a little,

        • Hi Mats
          Can’t really see why you want to modify the pully. Put your servo to middle position and add the pully with an offset to the closing position that will account for the different distances for opening and closing. The use the mapping feature of mrl to adjust the overall distance for your servo in use?

        • I posted an update to explain the probem.