How to choose suitable stepper motor for robotic arm?
A robotic arm is a type of mechanical arm, usually programmable, with similar functions to a human arm; the arm may be the sum total of the mechanism or may be part of a more complex robot. The links of such a manipulator are connected by joints allowing either rotational motion (such as in an articulated robot) or translational (linear) displacement. The links of the manipulator can be considered to form a kinematic chain. The terminus of the kinematic chain of the manipulator is called the end effector and it is analogous to the human hand.
Stepper motors are highly prcise, digitally controlled motoros that are able to provide reliable opeation without using detectors to sense or indicate position. The opeation of the motor is controlled though electical pulses. The diection of current flowing through the windings of the motor is switched with each pulse. The electrical pulse is converted into shaft rotation in steps of a fixed angle. Together with the driver,it constitutes an open loop system, which is cost effective and simple to constuct.
The key factors to select the stepper motor and drive:
1. Speed: If you need high speed, you should select the motors of larger current and smaller inductance, to increase the input power, and use the drive with higher supply voltage.
2. Holding Torque: Holding torque is one of the main parameters to choose stepper motor.If the load is large, you should use high torque motors. larger holding torque, larger frame size of motor.
4. Positioning accuracy and vibration: To determine if it needs to do the segment, the number of segments required.
5. Current and Voltage: To select the drive based on the current, segmentation and voltage.