You can get DC Servos, Google "DC servo motor", modern ones will probably be brushless and might work on lower voltages but I don't know if DC has any advantage over AC, they both need sophisticated electronic drives. Main things you need to know is how fast your axis need to move and how much torque is required to move it. For example, your robot has an arm that swings at the shoulder, how much torque is required to swing it from vertical to horizontal and hold it there and how fast. How much weight will it be required to lift, etc, etc.
Can the drive be connected to arduino to control the speed and read the encoder? If so, how can the arduino connected to read the encoder data? thorugh analogue pins?
Can't say without seeing the drives users manual, I've been retired from industrial work for 10 years and a lot has changed in that time, keep checking back here, there are many smart people and a few I know have extensive industrial and electrical engineering knowledge. Good luck.
What do you want to use your 'heavy duty' trainable robot for?Motors, controllers and power supply has to be spec'ed appropriately to the application. Servo motors (and motion control/kinematics in general) is typically beyond the skill of your average arduino hobbyist. I would recommend considering steppers. Hone your skill there first. They won't have the same power and speed, but they are less complex, cheaper and typically safer due to lower voltages. Heavy duty (industrial) collaborative robots are quite common but cost a pretty penny. I can think of half a dozen robot manufacturers off the top of my head. A quick Google would yield a bunch more.
Having said that there are modestly sized servomotors available now as stepper-replacements for
CNC machines - less featured than a full-on industrial servomotor, but many times less expensive too.
Their controllers typically just look like a stepper drive to the Arduino.