The Denavit-Hartenberg (DH) convention is a mathematical framework used to describe the kinematics of robots and other mechanical systems. It defines a systematic way of assigning reference frames to each link of a robot, allowing for a standardized method of calculating the position and orientation of each link relative to the others.
DH frames are assigned using a set of four parameters: d, θ, a, and α. d represents the distance between the current and previous frames along the z axis, θ represents the rotation about the z axis, a represents the distance between the current and previous frames along the x axis, and α represents the rotation about the x axis. These parameters can be determined by carefully examining the physical structure of the robot.
The DH convention simplifies the mathematical calculations involved in describing the motion of a robot. By assigning frames according to a standardized method, the DH convention allows for a consistent and efficient way of representing the kinematics of a robot. This makes it easier to analyze and control the robot's motion.
While the DH convention is widely used and has many benefits, it does have some limitations. For example, it assumes that all joint axes are either parallel or intersecting. It also does not take into account joint flexibility or other physical constraints of the robot.
The DH convention is used extensively in robotics research, as it provides a common language for describing the kinematics of robots. This allows researchers to compare and analyze different robots more easily, and also facilitates the development of new algorithms and control strategies. Additionally, the DH convention is used in simulation and modeling software to simulate the behavior of robots in various scenarios.