Industrial robots can be divided into two categories: serial robots and parallel robots. The serial robot takes an open-loop mechanism as the prototype of the robot mechanism; the parallel robot is a robot with one or several closed-loop joint coordinates associated with each other.
What is a tandem robot?
The tandem robot is an open kinematic chain robot, which is formed by a series of connecting rods connected in series through rotating joints or moving joints. The drive is used to drive the movement of each joint to drive the relative movement of the connecting rod, so that the end welding torch can reach a suitable posture.
What is a parallel robot?
A parallel robot refers to a closed-loop robot that is driven in parallel by a moving platform and a fixed platform, which are connected by at least two independent kinematic chains, and the mechanism has two or more degrees of freedom.
Parallel robots and traditional industrial serial robots form a complementary relationship in application. It is a closed kinematic chain. Compared with serial robots, it is generally composed of an up and down motion platform and two or more motion branches. The motion platform and motion One or more closed-loop mechanisms are formed between the branch chains, and by changing the motion state of each branch chain, the entire mechanism has multiple degrees of freedom that can be operated.
Comparison of serial robots and parallel robots
1、 Different structure
1. Tandem robot: Rods with high stiffness are connected by joints. Except that the rods at both ends can only be connected to the front or rear, each rod is connected to the front and rear rods through joints.
2. Parallel robot: a closed-loop mechanism in which the moving platform and the fixed platform are connected by at least two independent kinematic chains, and the mechanism has two or more degrees of freedom and is driven in parallel.
2、Second, the characteristics are different
1. Serial robot: reducer is required; the drive power is different, and the motor model is different; the motor is located in the motion structure, and the inertia is large; the positive solution is simple, and the inverse solution is complicated.
2. Parallel robot: no reducer is needed, and the cost is relatively low; all driving powers are the same, which is easy to productize; the motor is located in the frame, and the inertia is small; the inverse solution is simple, and it is easy to control in real time.
3、Different application occasions
1. Tandem robots: used in many fields, such as various machine tools, assembly workshops, etc.
2. Parallel robot: It is mainly used in precise and compact applications, and the competition points focus on speed, repetitive positioning accuracy and dynamic performance.
The main application areas of parallel robots:
1. Sorting, handling, packing, etc. in the food, electronics, chemical, packaging and other industries;
2. Metal cutting;
3. Similar to milling machine, grinding machine, drilling machine or spot welding machine, cutting machine.
4. Measuring machines, used as error compensators for other institutions
5. Cell manipulation robots in biomedical engineering, which can realize cell injection and segmentation, microsurgery robots, etc.;
6. Parallel robots are also widely used in submarines and tank driving motion simulators in the military field, vector nozzles of next-generation fighter jets, docking devices for submarines and space vehicles, attitude controllers, etc.