I have finally managed to program an ATtiny85 to act as a RC switch! The switch will work as a "poor-man's-ESC-reverse". I bought a cheap ESC for my Ballbot Project and it has no reverse mode, it is made for RC aeroplanes, so I have to implement a relay that acts as a "polarity-switch" to be able to make a reveres motion on the motors.
Finally we are up and running again, and I got some new parts in the mail yesterday!
Starting to look like a ball!
For the moment I have to glue the bows together, but that's OK.
Maybe in version two I'll manage to make them snapable.
I got a couple of new pieces today but I'm not completely satisfied!
I've misunderstood how the printing resolution works. I thought it would affect the surface roughness, but not the measurements.
This resulted in too thin material at the connection points
A quick update.
I had to change the tires of my wheels, the o-ring I meant to use had a diameter of 40 mm and I changed to one with a diameter of 45 mm instead.
New wheel diameter increased the top speed from 10 km/h to 11,5km/h 😎
I've been doing a lot of work since last time and there have been some changes in the design as well!
After I assembled a couple of parts in FreeCAD I realized that I had miscalculated (in my head) the size of some of them 🙁
I had to flip the base plate upside down to make room for the steering cradle and remove the friction wheels, because they wouldn't fit anymore. I also had to make the propel wheel larger to get better grip and to make the ball go a bit faster.
The approximate speed is now somewhere about 10 km/h, which is a quite good speed I think.
The base plate front view - with motors and steering craddle and its servo
Another post is up, about the propel system this time!
I have this idea that the ball will be driven with a motor and a small wheel inside a bigger ring, with a friction wheel underneath.
Sorry for my bad sketch
Finally I think we nailed the printing tolerance measurements! We also changed from white to black ABS filament, which seems to behave more accurately than the white one does.
I added some snap connections and push fittings to the new test piece so we can see if the printer has an accurate repeatability
Today I got my first "missing" parts to propel my ball 🙂 I'm going to make a simple and cheap speed controller by using two 30A brushed plane ESC, less than $9 each.
A couple of days ago I got a mail with an attached film clip of the first printed piece of the skeleton.
The day after, "Dubbear" came to my place and I got it in my own hands so that I could look, bend, squeeze and feel the first printed part of my very first CAD-project!
We took a look at my CAD-files and "Dubbear" showed me that my parts wasn't made as solids. I had simply misunderstood how to build the parts in a correct way!
Later on I did some googling and it turned out that it wouldn't be as much work as I feared to fix the parts into solids.
It's been quite some time since I last wrote something here, before the last post that is 🙂 so it's about time I do so!
It all started when I saw a post on Instructables about a Remote controlled basket ball robot. I immediately started to plan how I could make my own - who doesn't want a remote controlled ballbot!
Since I've got a lot of R/C parts laying around I figured it wouldn't be too expensive to gather the rest of the electronics needed, a DC motor and an ESC.
In the instructable the author used a 7" (17.8cm) hamster ball as the housing for his ballbot. 7" is quite small if you want to fit sensors and other fun stuff into the ball and really make it into a robot, not just a radio controlled ball. Continue reading
