Do You Know The 6 Basic Exercise Instructions?

Industrial robots are great helpers in the modern production industry. In factories, their power has slowly penetrated into the core, from low-end manufacturing for material handling, to high-end automotive manufacturing, new energy manufacturing, electronic assembly and other industries. Industrial robots are like cars researched in the last century, from mystery to entering thousands of households, and they have also slowly penetrated into the front lines of production.
Buying an industrial robot but not knowing how to use it is like a smartphone not being able to connect to the internet, so it is important to learn some basic operations of industrial robots.
This article will discuss one of the fundamental programming knowledge for industrial robots - motion commands.
The motion commands of industrial robots are the core programming commands that control their motion trajectories. These instructions define key parameters such as path type, target position, velocity, and attitude of the robot end effector (TCP), which are the basis for achieving precise motion control.
1. Free path
The "free path" motion command of industrial robots refers to the type of motion that uses joint interpolation to move the robot along a non-linear trajectory to a target point. It is suitable for large-scale movements (such as handling and palletizing) and can avoid mechanical dead points, program starting points, or safety points. It does not require precise path planning and does not require high path accuracy for operations.
The free path corresponds to joint motion commands (MoveJ/MOVJ), which are used to instruct the robot tool center point (TCP) to move from the current position to the target point at the fastest speed. The path is not fixed as a straight line, but is automatically calculated by the robot to achieve joint angle differences.
Its motion characteristics include ① uncontrollable path: the motion trajectory is usually an arc, even if the teaching point is geometrically straight, the actual path may still be a curve. Robots autonomously plan paths based on the difference in joint angles, and users are unable to accurately control the intermediate trajectory. ② Speed calculation: The speed of each joint is dynamically adjusted according to the "axis speed x path speed x speed multiplier" instead of a fixed Cartesian coordinate system speed.
2. Straight posture
Control the industrial robot to move to the teaching position in a linear interpolation manner while maintaining a constant posture (i.e. rotating part) of the end effector (tool). This means that during the motion, the tool center point (TCP) moves along a straight trajectory, while the robot's attitude axis (usually referring to the fourth, fifth, and sixth axes) does not undergo any rotational changes, ensuring that the tool maintains a fixed direction on the straight path. This is particularly important in applications that require high-precision path control, such as welding, handling, or precision assembly.
The center point of the robot tool (TCP) forms a straight path from the starting point (the endpoint of the previous instruction) to the target point (the teaching position). Motion is based on a Cartesian coordinate system (rather than joint space) to ensure path accuracy.
Motion instructions for industrial robots: posture straight line (data search instructions)
3. Posture curve
During the movement of the robot, the posture of the end effector (tool) continuously changes according to a specific pattern, while moving along a curved trajectory. The difference from ordinary curved motion is that ordinary curved motion only moves the robot's end along a circular arc path, but the tool posture (such as the welding gun angle) remains fixed.
The posture curve requires synchronous interpolation of the robot's four, five, and six axes (wrist joints) to ensure that the tool maintains dynamic posture adjustment on the curve path. Suitable for scenarios that require synchronized changes in tool posture and motion trajectory, such as welding and polishing.
For example, when welding a car exhaust pipe, it is a complex curve in 3D space, and the welding gun must move along the centerline of the pipe (curve path) during welding.
4. Round posture
Instructions specifically designed to achieve circular motion. Under what circumstances will this instruction be used? For example, machining an annular groove in the center of an aluminum alloy wheel hub. This can generally be divided into two methods: three-point circle drawing method and center circle drawing method.
Three point circle drawing method: Select three points on the circumference (starting point, middle point, and ending point), and the robot automatically generates a full circle trajectory through arc interpolation. This method is simple and intuitive. By taking three points on a plane circle, a circle can be determined without the need to determine its center and radius. It is suitable for most situations.
Circle drawing method: The starting point, center, and radius parameters need to be taught, and the robot generates a whole circle based on the center of the circle. The robot will draw a complete circle based on these parameters. This method requires more precise parameter settings, but can better control the shape and position of the circle.
5. Relative joints
Motion is performed through joint interpolation, relative to the previous position of the robot, and ends when the position is reached.
Relative joint motion is a motion method based on the joint coordinate system, which directly controls the various joint axes of the robot. Its characteristic is that the robot accelerates and decelerates simultaneously on each joint axis, moves to the target position at the teaching speed, and finally stops at the same time. The path of this type of motion is usually nonlinear and the motion state is uncontrollable, but the path is unique.
However, please note that the path of the robot from the starting point to the endpoint is not a straight line, but a curve composed of the motion trajectories of each joint axis. Therefore, this type of motion is more suitable in situations where path accuracy is not required.
Relative joint motion is suitable for large-scale movements such as handling, sorting, palletizing, and other tasks. Due to its motion path not passing through mechanical dead points, it is widely used in industrial production.
6. Relative posture straight line
A command that moves in a linear interpolation manner, characterized in that the robot moves from its current position (starting point) to the target position (ending point) in a linear path, and during the motion, the path of the robot tool center point (TCP) always remains in a straight line. This type of motion is suitable for applications that require high path accuracy, such as welding, gluing, etc
As a way of moving by linear interpolation, maintain the current posture and walk in a straight line relative to the previous position. After reaching the position, end. After entering the action menu, select "Relative"+"Posture Line", and then click the "Enter End Point" icon to enter the coordinate settings page.
The six robot motion commands introduced above may not seem simple, but they are already the most basic motion commands for robots. I think their significance is no less than the word roots in English words. Learning them can greatly improve the robot's operational level.