The Direct Drive principle is simple: the electric servomotor generates the mechanical energy needed to move the load, and the rest is done by the electronic-digital servo-control.
The first machines which were servo-controlled by means of drives, CNC and PLC assigned to these devices the only function of effecting the sequence of movements that were previously carried out “by hand” by the operator; precision and quality continued to be the result of the mechanical quality of the machine.
Second generation electronics introduced assistance and compensation functions to overcome some limitations or defects typical of mechanical and geometrical transmission: for example the compensation of axis linearity errors and inversion backlash.
With the advent of digital electronics, servo-controls overcome the performance limits of mechanical transmission, and make up for defects through feed forward functions. This attempt to go beyond the physical limits of a mechanical transmission system sets a new milestone:
The performance of servo-control electronics is limited by mechanical transmission components!
“Linear motors” and, for the rotating axes, “Torque” motors radically resolve the problem because they eliminate the mechanical transmission, therefore they define a new category of servo-controlled actuators the DIRECT TRANSMISSION or DIRECT DRIVE.
A Direct Drive system with Torque motor liberates the potential for electronic regulation to achieve an immediate benefit