Because the solderig robotmachine
is designed to work in the environment of quasi plane and narrow space,
in order to ensure that the robot can track the welding seam actively
according to the error information of arc sensor, the robot should be
compact, mobile sensitive and stable. In this paper, a small mobile
robot welding machine is developed for the narrow space characteristics,
According to the movement characteristics of each structure of the
robot, the robot mechanism is divided into three parts: wheel mobile
channel, torch conditioning mechanism and arc sensor by using modular
programming method. In addition, robot manipulator and motor driver are
integrated into robot mobile channel, which makes it smaller in size
because of its large inertia and slow response, mainly coarse tracking
of weld seam. Torch adjusting mechanism is responsible for accurate
tracking of weld seam, and real-time identification of welding error of
arc sensor. In order to reduce the influence of dust on moving parts
under the bad welding environment, the fully closed structure is
selected to improve the reliability of the system.
The requirements of soldering robot are not very high. Because it only requires point position control, as
for the moving track between the point and the point, there is no strict
requirement for the welding tongs, which is the reason that the robot
can only be used for soldering at the earliest. The robot should not
only have the ability of satisfying the load, but also the speed of the
point to point shift should be fast, the movement should be stable and
the positioning should be accurate, so as to reduce the shift time and
improve the efficiency of the operation.
The load of the soldering robot depends on the welding clamp. For welding tongs separated from
transformers, 30-45kg load robot can meet the requirements. However, on
the one hand, because of the long secondary cable line and large power
loss, the welding clamp is not conducive to robot welding inside the
workpiece; On the other hand, the cable is swinging with the robot, and
the cable damage is faster. Therefore, at present, more and more
integrated welding tongs are used. The welding tongs and transformers
are about 70kg in mass. Considering that the robot must have the ability
to meet the load, it can send the welding tongs to the space position
with a large acceleration for welding. Generally, the heavy-duty robot
with a load of 100-150kg is generally selected. In order to meet the
requirements of the quick shift of welding tongs in the process of
connecting spot welding. The new heavy robot adds the function of
completing 50mm displacement within 0.3s. This requires higher
requirements for the function of motor, the speed and algorithm of
microcomputer.
