Considering making a specialized bot for autonomous skills using a holonomic drive.(Qualified for MS World this past weekend and want to give programmer a challenge at next tournament). Does the orientation of the drive in the chassis make a difference? e.g. does it matter if the drive is parallel to the robot sides (with all wheels at 45 degree angles to the side or if the drive is a diamond inset to the robot sides with two wheels parallel to and two wheels at 90 degree angles to the sides. We would like to do the first as it shortens the drivetrain in relation to the length of the bot and setsthe wheels to the sides leaving more room in the center for the intake. Looking for the ability to go three wide on picking up sacks,
And off topic, is there an opinion as to the most predictable intake. With the positioning of the sacks along the walls, we were thinking a passive spatula or maybe a spatula with an over the top spinner assist.
With our robot, we designed our holonomic so we could have a wide intake which is about 2 1/2 sacks wide. We really like our set up but it took a while for us to find a perfect front anti tip wheels. We have a regular one but just shorted. In this video you can see 4886x with there holonomic x drive, but it was never really tested. And you said having to forward drive wheels and then 2 back wheels at a 90 degree angle, this is shown in this video. 2915a had it during roundup.
I perfer our holonomic setup.
While I love the idea, I do want to make sure you understand the ruling on what you have suggested. It sounds as if you are planning on building a second robot in addition to the one you will use to compete in the tournament head-to-head matches. You are not allowed to do this, as rule R1 in “Robot Rules” states:
Therefore, generally, during a single tournament, you can swap out your intake and/or arm, but you cannot change out your drive.
If I am wrong in my assumption, and you are simply changing your robot to be one specialized for the Programming Skills Challenge, and/or are building a second robot that will be used at this next tournament, including the qualification/elimination matches, then you may ignore this post.
Understood rules beforehand and would not be doing this unless we had qualified. Appreciate the concern though. Don’t know how good of a competition bot it will make but will run it never the less unless we can train the team to make changes NASCAR fast. You will still be stuck with the holonomic drive which concerns me even though 4886 has had great success with it. (The compact drive might not be the best for going over sacks but I am of the opinion that the best way to address that problem is to not drive on them in the first place).
The main difference you will have in the X or cross configurations of holonomic is the amount of wheels being driven at any time.
I am assuming your spatula is aligned facing front and not 45 degrees offset. If the top arm/scoop part is on a turntable then the rest of this is kind of moot.
With an X holonomic configuration all the motors will be driving in the north-south and east-west motions (aligned to the walls). That is your max torque configuration of driving when alinged to the walls. Moving 45 degrees to the walls along a diagonal with no spin would mean you only have two wheels driving at that time.
With a cross set up (or H set up), to go horizontally you will only drive two motors to drive you along. Will that lack of torque hurt you that much? 45 degree diagonal movement is your max driven power setting.
Whatever works for you is probably best. Other space/design considerations can come into play with 45 degree offsets of the wheels.