Application Scenario
First and foremost, an important aspect is the assessment of the imported robot, including what kind of application it will be used for and what manufacturing process it will be involved in. If the application needs to be completed collaboratively by a machine alongside manual work, then for common semi - automated production lines with human - machine integration, a collaborative robot should be an excellent choice, especially when there is a need for frequent workstation changes or production line shifts, as well as in cases where new torque sensors are used.
In the following discussion, I will mainly focus on articulated multi - axis robots. Such robots can adapt to a very wide range of applications, from material picking and placing to stacking, as well as special processes like spraying, deburring, and welding. Nowadays, collaborative robot manufacturers basically have corresponding robot solutions for each application. All you need to do is specify what you want the robot to do for you and select the most suitable model from different types.

Payload
Payload refers to the maximum load that a robot can carry within its workspace, for example, ranging from 1.5 Kg to 20 Kg. If you expect the robot to move the target workpiece from one workstation to another, you need to note that the weight of the workpiece and the weight of the robot's fixture should be added to its workload.
In addition, special attention should be paid to the robot's load curve. At different distances within the spatial range, the actual load - carrying capacity will vary.

Degrees of Freedom (Number of Axes)
The number of axes configured for a robot is directly related to its degrees of freedom. For straightforward scenarios, such as moving from one conveyor belt to another, a simple 4 - axis robot suffices. However, if the application scenario is in a narrow workspace and the robot arm needs to perform a lot of twisting and rotating, then a 6 - axis or 7 - axis robot would be a better choice.
The number of axes usually depends on the application. It should be noted that, provided the cost permits, choosing a robot with more axes for greater flexibility is a good idea. In this way, it is convenient to reuse the converted robot for another application process, which can adapt to more work tasks and avoid the situation of insufficient axes.
Robot manufacturers tend to use slightly different names for axes or joints. Basically, Joint 1 (J1) is the joint closest to the robot's base. The subsequent joints are called J2, J3, J4, and so on, until they reach the end of the wrist.

Maximum Drive Range
When evaluating the target application, you should know the maximum distance the robot needs to reach. The selection of the robot is based not only on the load but also on the exact reach distance. Each company provides a set of charts to determine whether the robot is suitable for a specific application. This is about the robot's horizontal movement range. Pay attention to the non - working areas near and behind the robot.
The maximum vertical height of the robot is measured as the distance from the lowest point the robot can reach (usually below the base) to the maximum height (y) that the wrist can reach. The maximum horizontal distance is the distance from the center of the robot to the remote center of the wrist point that can be reached horizontally (x).