Is that a breakout board Is that a breakout board with a single component on it? Oh, I see, it also has two resistors and a capacitor, so probably a schematic taken from the datasheet’s example usage…
Let me see, DRV8830 is about $2.7, the passives and PCB are maybe $1.3 altogether in bulk, so that’s 60% margin, nice.
All details are avalaible on Indiegogo. Motee is based on DRV8830 so you can find more specs in a datasheet. Of course I2C is connect in parellel, but connecting of Motees is similar to connecting in series. You just plug a wires to first module and connect them to the next one, etc.
It’s a kind of breakout at all. We designed Motee to solder it directly to the motor (let me see any module connected in this way), we prepared a library much better then MiniMoto. Components are quite small (even 0102) so pick&place cost a bit.
Motee is designed to connect a voltage directly from the battery. So you need to connect power and SDA, SCL to first module and that’s all.
It doesn’t seem like using It doesn’t seem like using such tiny components is justified – there is a lot of room on the PCB. That seems like just bad/wasteful design.
How is the library better? Driving a motor is not exactly rocket science, all you need is set the speed, and perhaps also have a break function, for active breaking. I have a hard time imagining what you can improve there.
Connecting power in a chain like this is just asking for trouble. Sharing power cables, especially for such noisy and power-hungry things like motors is a really bad idea. Even if your wires are quite thick (the Dupont cables usually are not), the last motor in chain will generate quite a lot of noise for all the rest of them. The power traces on those boards also look very thin, that will make it even worse.
There are different sizes of components, 0102, 0406 and other. There is no final product, we are still prototyping. I think there will be one more version of prototype so maybe we will include your tips.
In library we implemented different types of start, e.g. soft-start.
We thought about troubles you mentioned but the most important part was testing. Everything works perfect, there’s absolutely no problems with connection.
I for one have no problem with this post and I think we should encourage this type of activity. Their product will suceed or fail on its merits. I hope either path gives them incentive to inovate and proceed with their dreams.
How did you test it? How How did you test it? How many motors did you chain? What kind of motors? Did you try it with some worn-out or low-quality motors too? Were they under full load? At full current? How about slightly over-current? How about sudden spikes?
How did you determine that “everything works perfect”? Did you actually look at the power voltage on an oscilloscope and the signal parameters are well within the parameters specified by the datasheet, or did it just happen to work for you for a moment?
Did you try it with parts from different batches? What if the parts that you tried happened to be simply exceptionally good?
Sometimes i feel like early bird/ free samples are just a way to cut costs of testing and validating.
It would be a good idea if the motor drivers already come soldered on the motors, so it’s easier for final users and no chance to pick unsuitable couple of motors and drivers.
