Industrial Robotic Arm
Robotic arm forms a key part of industrial robotics. With tools mounted onto the robotic arm, a variety of different jobs such as soldering, painting and palletizing can be performed. There are several types of robotic arms currently employed in a wide range of industrial applications, namely - cartesian, cylindrical, polar and articulated robotic arms. An articulated robotic arm is the most popular type and has a higher DOF (Degree of Freedom), small size and wide operation range, as well as capability to avoid obstacles within a small space.
An articulated robot arm typically consists of rigid rods and rotatable articulations. A servo control system is used to control servo motors which drive articulations to rotate. It includes three modules: servo motor control, sensor and central control modules. Servo motor control module integrates a MCU, a motor driver, an encoder and a current sensor. Based on instructions from central module, MCU sends control signals to the motor driver which then amplifies the signals to drive motor to rotate. Encoder and current sensor are responsible for monitoring motor and returning feedback info to the MCU to ensure proper operation of servo motor. The sensor module involves many types of sensor such as proximity, image, pressure and LVDT sensors, which are used to collect data regarding robot arms’ motion behaviors and send to central control module after being processed by signal conditioning circuit. Central control module has a DSP and PLC module. DSP calculates motion trails and parameters of articulations based on data provided by sensor module. Then it sends the results to servo motor control module through CAN bus so that the required operation can be implemented by robot arms. PLC module provides a human-machine interface through which users can set programs to control robot arms. Additionally, PLC module has interfaces for connecting panic button and different types of relay which are used to control tools attached on robot arms.
With the advancement of robotics and artificial intelligence, robotic arms would become smarter and would be employable in more applications in the near future.