Application Analysis of Stepper Motor in Robot Design

Stepper motors with low-speed, high-torque equipment make transmissions shorter, which means higher reliability, higher efficiency, smaller clearances and lower costs. It is this feature that makes the stepper ideal for robots because most robotic motions are short-range requiring high accelerations to reach low cycle times. The power-to-weight ratio is lower than that of a DC motor. Yamatake Electric believes that most robotic motion is not long-distance high-speed (and therefore high-power), but usually involves short-distance stop and start. They are ideal robots at low rpm and high torque.

All ST robots have encoder feedback which is relative to the software motor count. In the event that any errors cannot be corrected, the system will stop. Therefore, the integrity of the system is much higher.

Therefore, the advantages of using stepper motors in robot design are as follows:

1 It is cheaper for stepper motors of the same performance.

2 stepper motors are longer life than brushless motors.

3 as a digital motor can accurately locate no hunting or overshoot.

The 4 drive module is not a linear amplifier which means less heat sink, higher efficiency and higher reliability.

The 5 drive module is less expensive than the linear amplifier.

6 There are no expensive servo-controlled electronic components because the signals originate directly from the MPU.

7 software is fail safe. The main control board has a stepping pulse. If the software does not work or crashes the motor stops.

8 electronic drive is fail safe. In the event of a motor lock with a drive amplifier failure, it will not operate. When the servo drive fails, the motor can still run and may be running at full speed.

9 speed control is precise and repeatable (crystal control).

10 The stepper motor runs extremely slowly if needed.

Stepper motor positioning device, so there can be no wrong work, such as excessive load will not slow down, but will stop. They cannot be used to exert the power of an independent position.

But the robot is the location of the device and is designed to enter the precise position without errors. A robot that reports an error and stops further actions in the first gear or collision.

In some low-speed stepper motors, resonance synchronization and delay losses can occur. Each stepper motor driver is controlled by an independent microprocessor, and the pseudo sine of the drive motor is called a microstep. The microcode watch resonates and automatically switches the phase and current to compensate. In micro-step mode running on a silent drive, the motor can be seen in the video over the entire speed range.