I just had an idea come to mind regarding my caster problem I've had for a while.
I have a round robot base, with 3.5" foam wheels on both sides. On the front and rear I have omniwheel casters.
Here is an out of date 3d model:
The problem was the suspension. I read up on Admin's one-piece suspension tutorial, but that won't work for me, because I really don't have the resources to design something like that, and besides my robot is truly in development, and the weight will be ever changing.
The second thought I had was to use an R/C suspension type system. But that is to complex, and requires engineering.
I ended up coming up with something on my own using small compression springs, and a long bolt, and that was a flop!! total garbage.
Then I just had this idea of a way that the robot itself could control the height of it's own casters. It would also be able to 'lean' forward and backward.
One could mount two servos, one in front and one in back with sail arms.
The servos would have to be strong enough to hold the weight of the robot when leaning, and fast enough to catch itself if need be (that way if both casters are in the up position, then it would be using its balancing functionality) The servo arm would also have to be strong in that not only to support weight, but when the robot is turning it will exert forces on the sides trying to bend the arm.
Also, if a gyro/imu/accelerometer is also used, the robot can tell when it is level, and if not it can level itself with these omniwheel casters on a servo.
Another thing, if the designed weight of your robot in development increases, you just upgrade the servos and servo arm.
Does anyone know of any servo and servo arm specs that would be a could starting point for me? My robot base has a 9" diameter btw. not sure how much it weighs. I do however plan on stacking it and adding two arms, and a robot vision system.