Hi All
When the kids with the massive sound systems in their cars bolt an extra 2000 watts of speaker to the roof of the car they still use their existing CD player, all that they do to drive the new and bigger mess is replace the power amplifier with a bigger, more capable one.
Why can this not be done in the CNC and Robotics world with regard motor drivers?
If you have a little NEMA17 and you replace it with a MUCH larger stepper, the chances are that whatever lightweight h-bridge is there will probably get fried (maybe along with a whole bunch of other stuff.)
Now falling around the internet trying to find an h-bridge to replace the lightweight one you have takes lots of time and these things are normally the same cost as your grocery bill.
So why not simply add a "power amplifier" onto the existing pins that go to the motor and plug the motor (and the high power source) into that to do the heavy lifting?
The reason I am asking is that I am trying to build a small proof of concept robot arm which will be powered by puny little RC servos so that I can develop and test a software design I am thinking of.
Now these can be driven by small little .6 amp h-bridge chips but what happens when I go full size?
At that point I will probably be using something like a windscreen wiper motor to get the power I need (using reduction gearing of course).
That little .6 amp chip will simply explode the first time I power up the motor.
So why can I not use a simple "POWER" amplifier between the existing output and my new monsters?
And if I can, does anyone have some ideas about what to use and what all is needed?
Anyone from South Africa (and probably a whole bunch of other countries) will know that once you have found what would be the ideal solution it is probably not available locally.
Then if you buy it from overseas, the shipping kills you because it is in most cases it is well over the original price of the item and right there it becomes a "totally not viable" option.
Call it a "power amp", "amperage booster", "high power booster" or whatever you wish, using the existing, dialed in and reliable h-bridge chip to drive the "power amp" would definitely be a lot cheaper than replacing the whole unit and it can probably be built using discrete components that are available locally, on its own board, with its own heat sink and maybe with its own fan to keep things cool.
The guys with audio amp experience probably know how to do this so that the "sound" does not get distorted etc and this will probably work well using a minimum of parts and saving us a lot of pain and money.
Anyone with ideas as to how to do this because I am at the point where I have to buy the h-bridge chips for the test bot and would love to use the low powered option (RC servos can run directly of an Arduino but 5? Rather not take the chance!!!) and have a viable path forward to the big motors that does not involve doing circuit rebuilds and tuning all over again.
Thanks for reading and solutions would really be appreciated.