Controller directs four robots and peripherals

Robot controller that can handle 36 axes simultaneously operates four industrial robots and synchronises them with gantry systems, linear tracks and rotary indexers and other peripherals.
Ten years ago, at the request of Toyota and other car manufacturers looking to increase the versatility of their welding systems, Motoman was the first to introduce and patent the simultaneous control of two 6-axis industrial robots. Now the company has introduced a new controller, the NX100, that can handle 36 axes simultaneously, allowing the movements of four industrial robots and peripheral equipment such as gantry systems, linear tracks and rotary indexers to be synchronised. There are two main reasons for manufacturers wanting synchronous systems.

First, having another robot hold and manipulate the part for welding, or indeed machining, painting, gluing or any other process, eliminates the need for expensive jigs.

Second, productivity can be doubled, trebled or quadrupled by having two, three or four robots working on a part simultaneously.

What distinguishes robot programming via Motoman's NX100 hand-held pendant is that the motions of all robots are controlled as a single entity, rather than having to program one first and subsequently the other robot(s) to fit in with the motions of the first one, two or three.

Fully synchronous programming results in no cross-talk between separate robot controllers and hence no time lag between their relative movements.

In practice, savings of up to 25% in cycle times can be achieved.

Moreover quality is normally enhanced.

For example, a weld bead may be laid more accurately in the absence of hysterisis in the system and there is no risk of burning through the metal if the arc-off command is received slightly later than the instruction to stop the torch.

The Windows-based, colour controller incorporates ample digital I/O capability for switching welding power supplies, paint spraying units, machine tools or other equipment.

There is flexibility in the way the external axes are configured, in groups of three so that they may be switched off for repair while the other robots continue to operate.

The control incorporates refinements such as variable collision sensitivity, whilst advanced robotic motion control optimises acceleration, deceleration and speed for circular and corner movements.

Likewise, inertial compensation via the path control function maintains path accuracy during high-speed movements.

An Ethernet card is built in as standard for good communication with the robots and peripherals.