Saturday, October 4, 2014
As you can see, the sphere sections are reinforced using some T-shaped aluminium brackets for supporting and holding the plastic (PC) sphere sections. This made a huge difference when it comes to rigidity. On MKII the ribs isn't really needed, simply because of the aluminium brackets that is shaped to match the inner part of each sphere section perfectly.
The main challenge with MKI was that it wasn't able to roll in a straight line of path, only in a curved direction. Having only one DOF (degree of freedom), or only one servo motor for each of the six upper sections made it very challenging. It might be possible to make a more complex linkage system that gave the upper sections a better motion when rolling. Not sure how though..
Having 2 DOF would make it easier to control, so that the upper and lower sections move in a symmetric motion.
The challenge was to make the motors fit inside the upper section without getting in conflict with the electronics.
Compared to the leg section, the femur and tibia sections are mounted very different. One advantage is that the servos in the upper section draw very little energy when holding the ball shape. To make enough space for the upper sections I also had to make new leg sections.
All these hardware updates also made MKII a lot heavier. So he upgrade the servos to 24x HSR-5990TG (all femur and tibias), 6x 5980-SG (coxa) and still using the same HS-5645MG (inner body servo).
The new upper section has a lot more freedom.
The code is still a WIP (work in progress)
the new upper section has a lot more freedom.
awesome :) its like a ball and it walks :) great !
ReplyDeletehow much is this?
wow
ReplyDeleteCool tech .
ReplyDeleteamazing looks like a ball
ReplyDeleteit looks funny but cool :O
ReplyDeletewhats the point of having this?
ReplyDelete