sto cercando di portare avanti il progetto di un accordatore robotizzato per chitarra. Per girare i pistoncini serve una coppia non trascurabile quindi ho preso un motore con le seguenti caratteristiche
5 2/11 : 1 Planetary Gearbox, Good Torque and Good Speed 0.347° Step Angle Gearbox Motor can produce 16.2 kg-cm holding torque @ 1.68A NEMA-17 Bipolar 4-wire Maximum Speed of 118 RPM @ 12V (with 1063 Motor Controller)
Per controllarlo ho anche acquistato lo shield dell'adafruit che permette un semplice controllo in Matlab e di controllare 2 stepper alla volta 4 dc e 2 servo: mi sono accorto ormai tardi che nel datasheet dice questo:
Current requirements: The second thing to figure out is how much current your motor will need. [u]The motor driver chips that come with the kit are designed to provide up to 600 mA per motor, with 1.2A peak current. Note that once you head towards 1A you'll probably want to put a heatsink on the motor driver, otherwise you will get thermal failure, possibly burning out the chip.[/u] On using the SN754410: Some people use the SN754410 motor driver chip because it is pin-compatible, has output diodes and can provide 1A per motor, 2A peak. After careful reading of the datasheet and discussion with TI tech support and power engineers it appears that the output diodes were designed for ESD protection only and that using them as kickback-protection is a hack and not guaranteed for performance. For that reason the kit does not come with the SN754410 and instead uses the L293D with integrated kickback-protection diodes. If you're willing to risk it, and need the extra currrent, feel free to buy SN754410's and replace the provided chips. Need more power? Buy another set of L293D drivers and solder them right on top of the ones on the board (piggyback). Voila, double the current capability! You can solder 2 more chips on top before it probably isnt going to get you much benefit
Rischio di bruciare tutto con quel motore?
Grazie in anticipo.