Imagine a component that meets every functional requirement in a CAD model. Can it still create trouble on the production floor? In short, yes.

Perhaps the complex geometry may require an expensive or time-consuming machining operation or a molded feature may be difficult to release from the tool. It’s possible that two parts could fit together correctly, but there’s no practical way to locate them during assembly. What happens if a smooth plastic housing leaves a robot with no reliable place to grip it?

In all of these examples, the design itself is functional. These are manufacturability issues.

WHAT IS DESIGN FOR MANUFACTURABILITY?

“Design For Manufacturability” is the practice of designing a product for efficient production at the required volume and level of quality.

In a conventional process, teams will work on a design first, then determine how the factory will make it after the design is complete. When engineers place a priority on DFM, they’ll evaluate the proposed design alongside the manufacturing process instead.

You may see the term phrased alternatively as “Design For Manufacturing” or shortened to “DFM.” There’s also “Design For Manufacturability and Assembly,” which expands the same approach to include the way individual components come together during production.

In all cases, the idea is to create parts that are well-designed for efficient manufacturing and fast ROI, which makes it easier to automate production and manufacture at scale.

DESIGN FOR MANUFACTURABILITY CONNECTS PRODUCT AND PROCESS

Remember the functional CAD model with the machining and assembly issues? If a manufacturer is following design for manufacturing principles, those issues will get identified in a DFM review before production, while design revisions are still easy to make.

The product must be connected to the process. Wherever possible, the design must reduce unnecessary part complexity and opt for the most suitable materials. Engineers will also have to consider assembly access and tolerances in relation to process capability. They’ll evaluate each decision according to how the part will be physically fabricated and handled on the line.

AUTOMATION DEPENDS ON DFM FOR EFFICIENCY

Human operators can compensate for variation in ways that machines cannot. A person can rotate an oddly shaped part in their hand and recognize its correct orientation or adjust their grip when a component arrives slightly out of position. It’s easy for a person to feel when an assembly has been seated incorrectly.

Automation demands precise repeatability. Unlike humans, when automated equipment is doing the job, it needs defined features and predictable conditions to repeat a process quickly.

A robot needs a contact point that’s always in the same place at the same time, with a surface or locating feature that establishes position. A vision system can’t do that without a clear view of the feature it must inspect. The feeder also needs enough geometric distinction to separate one orientation from another.

For these reasons, design for manufacturability is central to automation planning. The design must always account for how equipment will identify the part and control it during each process. Every step must prioritize consistent part orientation.

PART GEOMETRY CAN HELP OR COMPLICATE ROBOTIC HANDLING

Even tiny design features can help your automation system. For instance, here are a few features that work well to eliminate automation complexities:

• Keyed features are convenient because they can prevent components from entering a fixture backward.
• A flat gripping surface is also a big benefit — it gives your end-of-arm tooling a stable contact point.
• If you’re using vacuum handling instead, it demands a consistent flange.
• Adequate spacing around each assembly point helps robotic tools because they’ll have the clearance they need to operate.

The reverse is also true — tiny features can cause big problems.

• Parts with totally symmetrical exteriors can be difficult to orient.
• Flexible components tend to deform inside a gripper.
• Tight nesting risks blocking camera access.
• Excessively broad tolerances lead to position changes and may end up exceeding the adjustment range of the tooling.

It’s possible to engineer around these conditions, but each workaround could add more equipment or controls to the process. DFM-focused product revisions are more likely to solve the same issues at lower cost.

DFM REVIEW SHOULD HAPPEN BEFORE AUTOMATION DESIGN

A finished product design gives an automation team a fixed set of constraints, potentially with cumbersome manufacturing problems to work around. The earlier you can start the conversation around manufacturability, the more room you have to improve the part and the manufacturing process together.

In your DFM review, make sure to:

• Cover how components exit upstream equipment
• Establish how they will be presented to the next operation
• Consider gripping features and fixture location
• Account for inspection access and reject handling

This is not to say that every product must be redesigned for robots. However, if your goal is to achieve efficient, scalable robotic automation, the automation team must understand the product early enough to identify avoidable complications.

Jerit Automation frequently works with manufacturers whose products require specialized handling or inspection. It’s always ideal to get our engineers involved in the planning stage so we can help you evaluate part presentation and automation feasibility before those decisions become expensive to revisit.