Better Software Tools Help Machine Builders Reap the Benefits of Mechatronics.

Newer software programs intended for machine builders take advantage of mechatronic principles and easily blend the necessary and different engineering disciplines.

By John Pritchard, Global Product Marketing Manager
Kinetix Motion Control, Rockwell Automation

Traditionally, machines have been designed and built using individual mechanical, control, and electrical design teams — that work independently to produce separate pieces of the whole system. Often, the mechanical team will turn the design over to the controls team and hope they can integrate the software and controls before control and programming issues are addressed. The machine might deliver substantial performance and flexibility advantages, but typically the marriage of the mechanical functions with the control system is not optimal; it is merely sufficient.

Ratio analysis, from Rockwell Automation’s Motion Analyzer software, eases the selection of gearboxes, timing belts and ball screws. It provides an “at-a-glance” view of any necessary trade-offs.

A synergistic blend between the different engineering disciplines is needed to make the mechanical design and the electrical system that drives it work in harmony. Mechatronics principles can deliver this harmony.

With an interdisciplinary approach, machine builders can bring engineering processes closer together, to improve communication and expand the available knowledge base. Such an approach lets you configure and integrate the pieces up front and reduce the chance of encountering problems at the controls stage later that would require changes in the original mechanical design. This concurrent engineering approach lowers design and development costs, adds more functions, and produces a more robust, balanced design.

Better Input

A successful mechatronics design depends on the ability of a cross-functional design team to communicate, collaborate, and integrate. A single project team helps ensure collaboration that is more inclusive and removes many of the obstacles that exist between engineering departments — barriers that often restrict the exchange of ideas and the free flow of information.

Some machine builders even include automation suppliers during this collaborative effort and bring them on board early. With the supplier as a consultant, machine builders can leverage industry knowledge and standards expertise, as well as share best practices for the technology.

The Torque analysis feature shows where the motor “consumes” torque. Transmission losses are sometimes factored in, but rarely checked versus load losses. Torque analysis makes checking simple and enables rapid “what if” analysis if improvements are required. If the majority of the torque is used to move the load, the design is sound. If over 75% is lost in the transmission, it’s back to the drawing board.

Real World Analysis

Due to the complex relationship of forces and motion, a persistent challenge for machine builders is calculating accurate component and system lifetime estimates. Often, designers tend to either undersize or oversize components.

Advanced software tools, however, help size and select the appropriate motion control system for the application. With these tools, they simply enter information about the load and how it needs to move, and the software selects a suitable motor-drive combination.

Tolerance analysis plots application data, such as move time, mass, losses and ambient temperature, against “health parameters” for the system. The ability to see which parameter hits 100% tells them the limiting factor. The software rapidly analyzes the system’s tolerance to changes and alerts you to any marginal design issues.

From a pull down menu, scroll through catalogue numbers and select an actuator. Complex calculations and manufacturers’ specifications have been integrated. These tools also help them avoid oversizing by automatically choosing the right transmission ratio, which helps reduce design time and errors that would have to be corrected later.

In addition to sizing and selection, motion analysis software can offer simulation analyses. With simulation analysis, engineers can effectively investigate machine behavior and select a mechanical design, along with the controls and software that will maximize machine operation.

Similarly, dynamic thermal modeling (available in some software tools) can more accurately verify system operation by taking into account motor ambient temperature and altitude. This feature can be especially useful for machine builders exporting to countries with hot weather or fluctuating temperatures because it can help eliminate post-installation problems that weren’t identified during machine trials.

Other tools, like advanced tuning simulation, help predict how the machine will perform. With this feature, the engineers can rework any problems in the early stages before building the machine. The software emulates tuning an axis and then simulates the behavior of the load, motor, and drive. Then it factors in mechanical compliance or backlash for a realistic performance evaluation.

Several motion analysis programs offer simulation analyses, which helps machine builders define the relationship between mechanical components and system operation. Engineers can effectively investigate machine behavior and select a mechanical design, along with the controls and software that will maximize machine operation.

As current business drivers offer greater motivation for mechatronic development, forward-thinking machine builders are implementing the strategies and acquiring the tools needed to develop a more integrated design process. More importantly, the improved reliability and faster time to market that mechatronics affords means more satisfied customers and a more favorable bottom line.

Rockwell Automation www.ab.com/motion