jstarne1
ANT is doing a great job getting the first proto of the XLR6 ready to send to me to start working on so for the sake of planning I would like to listen to the communities ideas for a rover kit and rover base. The EZ Robot kit is a great place to start so we aren't trying to replace Roli. This is for the next level kit , more ridiculous add ons can be made later. I will share some of what we have in mind so far. As always all our projects are being developed for use with ez robot Ezb v4 but you can still use a v3 in them.
Rover kit , that's a top and bottom to make the whole Xl rover
+ misc parts like wheels
Rover base only, that's the bottom half of the Rover frame with wheels and a flat tray on top all molded from 80A shore urethane plastic
The Zero Degree Rover
want to go fast? Driving a skid steer base is difficult but you can switch modes. Lock the rear in place and turn only the front servos. ZOOOM...! This versatility is not found in any other rover base kit. 6Wd and individual motors for each wheel give power in a small package without noisy plastic gears. Gear reduction comes with its own problems. The motor pods are for a 40mm Nema 17 stepper. Alternate mounts can be swapped for 58mm Nema 23 steppers or even continuous standard servos. This is the staple of modular versatility!
Mini Zero Rover
J
Thanks for watching guys. The goal is for this platform to be well thought out and versatile. Building those options if thst we wish every other chassis had. I have tried over a dozen wheel types and that's one of the next things to be designed. Once there is a wheel design then the motor mounts will be designed to adjust ride height and have solid stiff suspension or off road with 100mm oil filled shocks. Two shocks for each wheel is possible for a heavy robot yet able to tackle terrain as well as the wild thumper. A advantage over thumper is the surface area will be 2.5 times greater on top for those who want to make their own top of the chassis.
The first is solid suspension with no shocks. This is for indoor use and mild outdoor ventures. This does not picture the Zero radius turn spindles.
This is the naked base with fully adjustable suspension. Using oil filled 100mm aluminum shock and springs , the right height and stiffness may be adjusted. Second is the adjustable "hard frame stop" . This adjusts the highest point the wheels can travel. In situations where heavy weight exceeds the shocks capacity the suspension rests on these stops. The shocks can be adjusted to intentionally rest the suspension on the frame but when uneven gaps in flooring are crossed the wheels reach down to maintain traction.
Here is the contemporary "smooth" rover top front view with comparison of hard and soft suspensions
I really like those mini shocks and they are oil filled also, they look like a good quality and sturdy shock. Very nice indeed :-}
More than likely they are the same shock as the hpi ones.
Lately I have been ordering parts and pieces off of Ebay from China, I cannot beat the prices, none of the stores around here even come close on the price and most of the time the shipping is very cheap or nothing at all, now I don't understand that at all.
I'm probably not as much of a community member as I feel like I am because I mostly just lurk but how far along are you on suspension development and are you open to suggestions on it? I wouldn't call myself a suspension expert but I have raced both onroad and offroad R/C and have some experience working with this kind of small scale suspension.
From looking at your sketches:
1. You probably don't want to do the suspension underneath the main body like that if is supposed to be an "off road" version. The suspension arms being underneath like that will reduce ground clearance and will have the potential to get hung up on rocks, sticks, and the like. The bottom should be as flat and smooth as possible to get over those kinds of obstacles without getting hung up on them.
2. You show the shocks being mounted in a straight up and down configuration. Most R/C every vehicle I have used has the lower part of the shock outside of the upper part of the shock. Having the shock straight up and down creates side loads on the shock as the suspension arm moves up and down through it's arc.With the shock at and angle it works much more efficiently. Also, with the shocks at an angle, you have the added benefit of the shocks being able to help stabilize the vehicle from side to side. A straight up and down shock configuration is not very stable in that regard. The picture below shows what I am talking about.
Anyways....thats just my 2 cents.