What Is a Parallel Robot?
A parallel robot, called English Parallel Mechanism, or PM for short, can be defined as a type in which a moving platform and a fixed platform are connected through at least two independent kinematic chains. The mechanism has two or more degrees of freedom and is driven in parallel. Closed loop institutions.
Parallel mechanism (Parallel Mechanism, referred to as
(1) No cumulative error and high accuracy;
(2) The driving device can be placed on or near the fixed platform, so that the moving part is light in weight, high in speed and good in dynamic response;
(3) Compact structure, high rigidity and large bearing capacity;
(4) The completely symmetrical parallel mechanism has better isotropy;
(5) Small working space;
According to these characteristics, parallel robots have been widely used in areas that require high rigidity, high precision, or large loads without requiring a large working space.
History of Parallel Robots
The emergence of parallel mechanisms dates back to the 1930s.
In 1931, Gwinnett proposed an entertainment device based on a spherical parallel mechanism in his patent (Figure 1); in 1940, Pollard proposed a space industrial parallel mechanism in his patent for spray painting of cars (Figure 2) After that, Gough invented a six-degree-of-freedom tire detection device based on a parallel mechanism in 1962 (Figure 3); three years later, Stewart first conducted a mechanical study of the mechanism invented by Gough and Its promotion application is the motion generating device of flight simulator. This kind of mechanism is also the most widely used parallel mechanism, which is called Gough-Stewart mechanism or Stewart mechanism (Figure 4) [2] .
Parallel entertainment device
| Pollard's parallel mechanism
|
figure 1 | figure 2 |
Parallel robot
| Gough- Stewart
|
image 3 | Figure 4 |
Application of Parallel Robot
(1) Motion simulator
Boeing 737-400 flight simulator
| CAE Flight Simulator
|
(2) Parallel machine tools
(3) Micro-operation robot
(4) Force sensor
Others: submarines and tank driving motion simulators in the military field, vector nozzles for next-generation fighter jets, docking devices for submarines and space vehicles, attitude controllers, etc .; cell-operated robots in biomedical engineering; Segmentation; micro-surgical robots; attitude adjustment devices of large radio telescopes; hybrid equipment, such as the Tricept hybrid robot module from SMT, is a successful example of modular design based on parallel mechanism units.
Other applications
Parallel robots are also widely used in other fields, including:
Submarine and tank driving motion simulators in the military field, vector nozzles for next-generation fighter jets, docking devices for submarines and space vehicles, attitude controllers, etc .;
Cell operation robot in biomedical engineering, which can achieve cell injection and segmentation;
Microsurgical robot
Attitude adjustment device of large radio astronomy telescope;
Hybrid equipment, such as the Tricept Hybrid Robot Module from SMT, is a successful example of modular design based on parallel mechanism units [3] .
