Seven-axis industrial robots vs. six-axis industrial robots, whats better?

a technical point of view, what are the problems with six-axis industrial robots , what are the strengths of seven-axis industrial robots ?

(1) Improve kinematic characteristics

In the kinematics problem of the robot , three problems greatly restrict the movement of the robot.

The first is the singular configuration. When the robot is in a singular configuration, its end effector cannot move in a certain direction apply torque, so the singular configuration greatly affects motion planning.

The second is the over-limit of joint displacement. In real working conditions, the angular range of motion of each joint of the robot is limited. The most ideal state is plus minus 180 degrees, but many joints cannot do this. In addition, the seven-axis robot can avoid excessive angular velocity movement make the angular velocity distribution more even.

The third is the existence of obstacles in the working environment. In industrial environments, there are many environmental obstacles, traditional six-axis robots cannot only change the posture of the end mechanism without changing the position of the end mechanism.

(2) Improvement of dynamic characteristics

For the seven-axis robot, utilizing its redundant degrees of freedom can only achieve good kinematic characteristics through motion trajectory planning, but we can also use its structure to achieve optimal dynamic performance.

The seven-axis robot can realize the redistribution of joint torque, which involves the problem of static balance of the robot, that is, the force acting on the end, the force borne by each joint are calculated through a certain algorithm. For traditional six-axis robots, the force of each joint is certain, its distribution may be unreasonable. However, for seven-axis robots, we can adjust the torque of each joint through the control algorithm, so that the torque borne by the weak link is as small as possible, so that the torque distribution of the entire robot is more uniform more reasonable.

(3) Fault Tolerance

When a robot malfunctions, if one joint fails, a traditional six-axis robot will be able to continue to complete the work, while a seven-axis robot can continue to work normally by readjusting the speed of the faulty joint (kinematic fault tolerance) redistributing the torque of the faulty joint (dynamic fault tolerance).

Whether the product perspective the application perspective, seven-axis industrial robots are still in the initial development stage. However, major manufacturers have been promoting related products at major exhibitions, which shows that they are still very optimistic about its future development potential.

The LBRiiwa seven-axis robot is designed based on the human arm, its integrated sensor system gives the lightweight robot programmable sensitivity very high precision. All axes of the seven-axis LBRiiwa are equipped with high-performance collision detection functions integrated joint torque sensors to achieve human-robot collaboration.

The seven-axis design makes KUKA's product highly flexible can easily cross obstacles. The LBRiiwa robot is made of aluminum weighs only 23.9 kg. It has two load capacities, 7 kg 14 kg, making it the first lightweight robot with a load capacity of more than 10 kg.

Can the domestically produced seven-axis robot achieve overtaking?

At present, the vast majority of my country's industrial robot companies have yet released seven-axis industrial robot products. Some of them said that they are developing related products will have related products available within the year, while other companies said that they are interested in seven-axis industrial robot products but have yet planned to design develop related products.

my country's robot industry has made great progress in the theoretical research of seven-axis industrial robots, but there is still a big gap between China foreign countries in terms of commercial products. The reasons are mainly the following two aspects:

First, the independent innovation capability is weak. There is a lack of original achievements innovative ideas in core key technologies. Compared with the advanced level of foreign countries, the overall technology of my country's industrial robots is more than ten years behind.

Second, the profitability of enterprises is low there is a shortage of R&D funds. The lack of core component technology has led to high production costs for enterprises. In addition, foreign manufacturers have cut prices one after another. In 2015, more than 70% of enterprises were in a loss-making state in their main business.

According to experts, the overall technology of my country's industrial robots is more than ten years behind the advanced level of foreign countries. The emergence of domestic seven-axis industrial robots shows that our research development of industrial robot technology is accelerating, but we should have a clear understanding that the gap is real. If we want to overtake others, we need to overcome the core technology difficulties as soon as possible, at the same time, we should also pay attention to the research development of next-generation technologies such as artificial intelligence, perception, recognition, drive control.