Introduce parallel robots and serial robots. Those who have studied high school physics are familiar with parallel and series circuits. Put, series circuits are one-way streets, and once blocked, all vehicles cannot pass through; Parallel connection refers to multiple lanes, with each lane being independent. Even if one lane is blocked, other lanes can still pass through.
1. Does this different link mode still hold for industrial robots?
Serial robots and parallel robots are different branches of the industrial robot family from a mechanistic perspective. They have their own advantages and limitations, and their appearances are also very different. This article introduces them to brothers, so that you will not be fooled by integrators when upgrading production lines.
The first one is a serial robot, which is more like a human arm robot
A serial robot is an open motion chain robot (which can be understood as an open chain, like a "straight chain", fastened one by one, without closure or crossing from the base to the end), like a human arm, from the shoulder to the wrist, each joint is connected in sequence to form a chain, which is more intuitive.
The structure of a serial robot is formed by a series of connecting rods connected in series through rotating or moving joints. This type of robot starts from the base and is connected in sequence through multiple rigid linkages, ultimately reaching the end effector (such as a tool or robotic arm). Each connecting rod is usually equipped with a driver (such as a motor), so four axis robots have four motors and six axis robots have six motors. The relative motion of the entire connecting rod is driven by the movement of the driver, thereby achieving the positioning and attitude adjustment of the end effector.
2. The characteristics of serial robots include:
1. Simple structure: composed of multiple rigid links and joints, it is relatively easy to design and manufacture.
2. High flexibility: Due to the independent control of each joint, the serial robot has a large workspace and high flexibility, making it suitable for complex trajectory motion tasks.
3. Multiple degrees of freedom: usually with high degrees of freedom (such as 5-6 axes), it can complete operations at almost any angle or trajectory.
4. Complex control: Due to its cantilever structure, each joint needs to support the weight of subsequent joints, resulting in low load capacity, and cumulative errors may affect accuracy.
5. High energy consumption: Due to the need for the driver to provide power for the subsequent connecting rods, the driving power of the front connecting rod is relatively high, resulting in lower overall efficiency.
Serial robots are widely used in industrial fields such as welding, handling, assembly, spraying, and other scenarios.
3. The second one is a parallel robot that looks like a "big spider", also known as a spider hand
A parallel robot is a closed-loop motion chain robot driven in parallel, generally consisting of an up and down motion platform with a moving platform and a fixed platform, and two or more independent motion branches connected.
A robot composed of one or more closed-loop mechanisms formed by the motion platform and motion branches, where the coordinates of the joint points are interrelated. By changing the motion state of each branch, the entire mechanism has two or more degrees of freedom that can be operated. Parallel robots developed by robots like Braun currently have five degrees of freedom and six degrees of freedom.
4. Characteristics of parallel robots
1). High stiffness: Due to the joint action of multiple branches, parallel robots have high rigidity and can withstand large loads.
2). High accuracy: Due to the absence of cumulative errors, its positioning accuracy is high, making it suitable for scenarios that require high-precision operations.
3). Fast speed: Parallel robots have fast movement speed and can efficiently complete tasks.
4. Compact structure: Due to its symmetrical structural design, it occupies a small space and is well-suited for use in limited areas.
5). Good dynamic response: Due to its lightweight design, it can quickly respond to control instructions.
Parallel robots are widely used in industrial manufacturing, healthcare, logistics and warehousing, food processing, electronic assembly and other fields.
The circuit example mentioned at the beginning is to help you understand the open and closed links of robots, but their working principles are significantly different.
Overall, these two types of robots have different characteristics and application areas, each with its own strengths. The choice of robot mainly depends on the needs of one's own production line. The serial robot has a simpler structure, easier control, and flexible operation, while the parallel robot's end platform is supported by multiple rods, with high rigidity and stable structure, thus performing well in precision operations.