Stephan Kloss, Jon
Shephard, Duncan Hand
Usage of robots for
manufacturing applications in the automobile, printed circuit board
and aerospace industry became standard practice during the last two
decades. However, most of these systems are linear 6-axis or 4-axis
SCARA (Selective Compliant Assembly Robot Arm) robots, comprising of
a single arm with motorised joints which provide the required
degrees of freedom, these systems are also known as SERIAL ROBOTS.
An alternative design
is the PARALLEL ROBOT, where the end effector is connected to the
base via multiple kinematic chains. Any two chains thus form a
closed loop. This is opposed to classical open loop mechanisms such
as the serial robot (e.g. articulated robots such as jointed arms).
- Disadvantages of
serial robots: low stiffness, accumulated errors, have to carry
- Parallel robots
potentially offer; increased accuracy, reduced weight, cheaper
implemented fibre optics into parallel manipulator for 3D ms
Integration of commercially available ms or ns laser into
Laser is fibre coupled;
Effector optics housing integrated into motion system to allow
3D movement of laser focus spot relative to workpiece
Output of fibre imaged with effector optics fixed in custom
Gas nozzle can be used for assist gas (ms processing);
Third axis acts as focus control.
Figure 1: Through-cut stainless steel sheet, 300 mm thick with cut
star shape in place (left) and, removed (middle). The scale markers
are 1mm. A closer detail of the cut is given in (right) where the
white square has 1mm sides.
Figure 2: Integration of ms laser (via optical fibre) into parallel