Thread: Hex Kiwi Drive
View Single Post
  #10   Spotlight this post!  
Unread 30-05-2016, 11:27
GeeTwo's Avatar
GeeTwo GeeTwo is offline
Technical Director
AKA: Gus Michel II
FRC #3946 (Tiger Robotics)
Team Role: Mentor
 
Join Date: Jan 2014
Rookie Year: 2013
Location: Slidell, LA
Posts: 3,636
GeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond reputeGeeTwo has a reputation beyond repute
Re: Hex Kiwi Drive

Quote:
Originally Posted by Cash4587 View Post
Although this is a cool idea and looks interesting it probably is not very practical. In most cases it would make the most sense to just do a 3 wheel kiwi..
Yes. The great advantage of 3 wheels is the relative insensitivity to irregularities in the drive surface. Unless you reach really high angles or high center on at least one side, all three wheels will carry a share of the robot weight, enabling the vector drive forces to add up as intended. With six wheels, it is rather easy for some of the wheels to come off the floor, sending the net drive force in unintended directions.


Quote:
Originally Posted by asid61 View Post
That might be a tad fast even for 6 CIMs, because of brownouts.
For brownout/gear ratio purposes, this is not the same as a 6 CIM skid/swerve. If you're driving parallel to two of the wheel axles, two of the CIMs do not contribute to the drive at all, and the other four are reduced about 13%. If you're driving perpendicular to two of the wheel axles, two CIMs are fully engaged and four are limited to about half contribution. Due to different efficiencies at different speeds and that you're drving different motors at different levels, things will get more complicated quickly. With a holonomic drive train, you should be more concerned about avoiding or escaping pushing contests than about winning them.
__________________

If you can't find time to do it right, how are you going to find time to do it over?
If you don't pass it on, it never happened.
Robots are great, but inspiration is the reason we're here.
Friends don't let friends use master links.
Reply With Quote