All these costly surprises have one common denominator: they were discovered too late, on the real line, instead of being eliminated in the virtual environment.

Simulating robot cells with DELMIA moves these decisions before the first screwdriver. Validate the configuration, trajectories and cycle times on a digital model before you spend a euro on the physical installation. This guide shows you exactly how the process works, from concept to actual controller, and why it matters to your budget.

What is robotic simulation and why it decides project profitability

Robotic simulation is the complete recreation of a production cell in a virtual environment. Robots, tooling, parts, fixtures, protective fencing, everything reproduced down to the millimeter. On this digital model you program movements, check accessibility and measure performance before any physical installation.

DELMIA, developed by Dassault Systèmes, is one of the reference platforms for this activity. The manufacturer presents it as a solution for designing, validating and programming robotic cells with speed and accuracy, according to DELMIA Robotics official documentation.

The practical difference is simple. Scheduling on the actual line blocks production. Every hour of downtime for testing and corrections means direct losses. Off-line scheduling, validated in simulation, keeps the line running until the new cell is ready to produce. The financial benefits of this approach I have detailed separately in the article on the cost-effectiveness of robotic simulation and cost reduction through offline programming.

For a decision maker, the question is not whether the simulation is worth it. It’s how much you lose without it.

Complete workflow: from concept to validation

The DELMIA simulation process follows a logical path in clear steps. Each step eliminates one category of risk. Skipping any of them moves that risk to the real line, where the correction costs ten times as much.

The complete path looks like this: importing CAD models and building the configuration, defining active equipment, off-line programming of trajectories, reachability analysis, collision detection, cycle time simulation, program conversion to real controllers and final validation. We go through them in turn.

This structured methodology is recognized in the literature. Manufacturing engineering research publications, such as ScienceDirect indexed studies on offline robot programming, confirm that phased virtual validation significantly reduces commissioning errors.

Import CAD models and create virtual configuration

It all starts with the right geometry. Import CAD models of the hall, equipment and workpieces into DELMIA. The more realistic the model, the more reliable the simulation.

This is where the first pitfall arises. Incomplete or inaccurate CAD modeling produces a simulation that looks perfect on the screen, but doesn’t correspond to the real hall. Missing fences, unincluded posts, approximate fixtures all become unexpected collisions on installation.

For existing equipment without CAD documentation, the solution is 3D scanning and model reconstruction. This industrial reverse engineering process transforms a real part into an accurate 3D model that can be used directly in the simulation setup. Without an accurate geometry of the existing environment, the validation of a new cell in an old hall remains incomplete.

Equipment definition: robots, grippers, fixtures, fixtures, conveyors

Geometry alone doesn’t move anything. The next step is to transform static models into active equipment with real kinematics.

You define each robot with its exact model: number of axes, joint limits, maximum speed and reach. DELMIA includes libraries of robots from leading manufacturers FANUC, ABB, KUKA, Yaskawa, FANUC, ABB, KUKA, Yaskawa, with real kinematic parameters, so that virtual behavior matches the physical one.

You do the same with tooling: fixtures, welding heads, glue application heads. You define the working point of each tool, because all the trajectories are calculated around it. You add the fixtures that hold the part and the conveyors that move it. The result is a complete cell in which every component moves exactly as it will in reality.

Off-line programming and path generation

With the cell complete, you start the actual programming. You define the points the robot tool passes through, the order of operations and the motion parameters. This is offline programming: you write the robot program without touching the physical robot.

The business advantage is straightforward. The engineer programs at the office while the existing line continues to produce. There’s no downtime and no repeat runs on expensive equipment. Market research by ABI Research on Dassault Systèmes’ offline programming solutions places this technology among the most mature in the industry.

Common mistakes at this stage are worth knowing in advance, because each one costs money. We analyzed them in detail in our article on the 5 costly mistakes in offline robot programming and how to avoid them.

Accessibility analysis and identification of dead zones

Before you optimize the movements, you need to confirm one fundamental thing: does the robot physically reach all the work points?

Accessibility analysis checks exactly this. DELMIA calculates whether each programmed position is within the robot’s reach, taking into account all joint limitations. Inaccessible points, dead zones, appear immediately on the model.

This check changes high-impact design decisions. If a point is inaccessible, you have clear options: reposition the robot, choose a larger radius model, or move the part. All these decisions are made now, on-screen, when the cost of change is zero. Discovered on the real line, the same problems mean redesigns, new equipment orders and weeks of delays.

Collision detection and movement optimization

The robot reaches all points. But does it get there without hitting anything?

Collision detection automatically checks every movement against all objects in the cell. DELMIA signals any contact between robot and fixtures, between arm and fence or between two robots working simultaneously. It checks even dangerous approaches, not just actual collisions.

For cells with multiple robots, coordination of movements becomes critical. Research on collision checking in human-robot collaboration, documented in studies such as those on explicit hazard zone representation, shows how important this step is for operational safety. An undetected collision in simulation becomes a damaged robot and a production stop in reality.

After eliminating collisions, you optimize trajectories for shorter and smoother movements. Every second saved per cycle is multiplied by the number of parts produced per year.

Cycle time and throughput simulation

Here the simulation delivers the figure that management expected: how much the cell realistically produces.

DELMIA calculates the cycle time based on the robot’s actual movements: accelerations, decelerations, technological pauses. This is not an optimistic estimate, but a time derived from the actual kinematics of the equipment. The cycle time gives the production throughput: how many parts per hour, per shift, per year.

This figure has direct business consequences. You use it to size your capacity, make promises to your customers and calculate your return on investment. A cycle time validated in the simulation is a promise you can keep. A roughly estimated cycle time is a source of contractual penalties.

Case studies from the automotive and aerospace industry, such as the Dassault methodology analysis documented by the European Green Digital Digital Coalition, demonstrate how virtual cycle time validation prevents over- or undersizing of lines.

Program conversion and export to real controllers

The program validated in the simulation does not yet speak the language of the physical robot. Each manufacturer, FANUC, ABB, KUKA, uses its own programming language. Program conversion (post-processing) does the translation.

DELMIA transforms the trajectories and programmed logic into the native code of the specific controller. The resulting program is loaded directly on the real robot without manual rewriting. This is when simulation work turns into actual production.

The quality of the conversion module determines how faithfully the program transfers. A correctly configured module means that the real robot reproduces exactly what you validated virtually. This closes the loop between the digital and physical worlds.

Final verification and validation

Before transfer to the real line, you run the cell through a full validation. You run the whole program in simulation, from end to end, checking that all the previous steps confirm together.

Confirm accessibility of all points, absence of collisions, target cycle time and correctness of exported code. This final validation is the digital equivalent of a technical acceptance. Everything that passes it should work identically on the real equipment.

This is where the real value of the methodology can be seen. The difference between validation and actual commissioning is an important topic, which our Process Validation and Simulation Services pillar fully covers. Rigorous virtual validation drastically reduces physical commissioning time.

Frequently Asked Questions

What is robot cell simulation with DELMIA?

Simulating robot cells with DELMIA is the complete recreation of a production cell in a virtual environment, including robots, tooling, fixtures and conveyors. On this digital model you program movements, check accessibility and measure cycle time before any physical setup, eliminating costly risks otherwise discovered on the real line.

What is the difference between offline programming and real online programming?

Scheduling on the actual line blocks production, every hour of downtime for testing means direct losses. Off-line scheduling, validated in DELMIA simulation, is performed in the office while the existing line continues to produce. The resulting program is loaded on the robot only when the cell is ready to go into production.

What checks affordability analysis in a robotic simulation?

The reachability analysis confirms whether the robot physically reaches all working points, taking into account joint limitations. Inaccessible points, called dead zones, appear immediately on the model. This way you can reposition the robot, fixture or part when the cost of change is zero, not after physical installation.

How does DELMIA help to correctly estimate cycle time?

DELMIA calculates the cycle time based on the robot’s actual movements, including accelerations, decelerations and technological pauses. The result is a figure derived from the actual kinematics of the equipment, not an optimistic estimate. Based on this validated time you size the line capacity and calculate the return on investment.

What is program conversion (post-processing) in DELMIA robotic simulation?

Program conversion is the stage where the program validated in the simulation is translated into the native language of the real robot controller, specific to each manufacturer such as FANUC, ABB or KUKA. The resulting program is loaded directly on the physical robot without manual rewriting, closing the loop between the virtual and the real environment.

Why outsource DELMIA simulation instead of doing it in-house?

DELMIA requires expensive licenses, specialized engineers and experience gained on real projects. For most companies, training this skill in-house does not make economic sense. Outsourcing provides access to validated output, configuration, ready-to-load programs and confirmed cycle times without the investment in infrastructure and training.

Why outsourcing DELMIA simulation makes sense for your business

DELMIA is a powerful tool, but it is not a simple tool. It requires expensive licenses, specialized engineers and experience gained on real projects. For most companies, training this skill in-house does not make economic sense.

Outsourcing the simulation to a specialized partner gives you access to the result without the investment in infrastructure and training. You receive validated configuration, ready-to-load programs and confirmed cycle times on which you build your business decision with confidence.

If you are preparing an investment in a robotic cell or want to validate an existing project before installation, our team can take over the entire DELMIA simulation process. Contact us for a discussion about your project and find out exactly what risks we can eliminate before they affect your budget.

The post Complete guide to simulation and validation of robot cells with DELMIA appeared first on CenterLine România.

Offline programming solves this paradox. You develop trajectories in a virtual environment. Validate the process without stopping production. Download the program to the robot only when you’re sure it works.

The benefits are documented and consistent:

• Reduce commissioning time by 50-70%
• Eliminate costly errors discovered on line
• Optimize cycle time before equipment investment

Read more about these advantages in the detailed analysis on Automate.org.

But there is a problem. Many integrators report frustrating situations. Simulations “look good on the screen, but don’t work in reality”. The cause is almost always one of five typical mistakes. We analyze them one by one.

Mistake 1: incomplete CAD models of the cell

In short: A rough 3D model produces real collisions where the simulation showed free space.

The simulation is only as good as the models it uses. If a console, cable or pipe is missing from the model, the robot will hit the obstacle on its first real run.

Why it happens

The problem arises for three common reasons:

• Oversimplified models. Fasteners and carriers are reduced to elementary blocks. Details that take up critical space are lost.
• Out of sync documentation. The cell has been modified over time. New sensors, upgrades, service interventions. The documentation hasn’t kept up.
• Approximate customized devices. Custom grips and fixturing are modeled without actual fitting tolerances.

How to prevent the problem

Invest in rigorous documentation before simulation. For old or modified cells, 3D scanning is the quick solution. You get a true state model in hours, not days.

The full methodology is described in our guide on industrial reverse engineering.

Explicitly model elements that do not appear in standard CAD. Power cables. Hoses. Auxiliary structures. Accessories added later. A complete model drastically reduces the risk of collisions.

Mistake 2: Neglecting range and singularities

In short: Robots have physical limits. Ignoring them means unreachable working points and blocked trajectories.

Every robot has a finite workload. Ambitious programmers often place working points at the limit of this volume. Or even in areas with singular configurations.

What are singularities

They occur when the robot’s axes align unfavorably. Movement in Cartesian space becomes impossible. Or it requires infinite speeds on one of the axes. Result: controller error, trajectory locked.

For 6-axis robots, there are three main types:

• Shoulder singularity – when the wrist aligns with axis 1
• Elbow singularity – when axis 3 is fully extended
• Wrist singularity – when axes 4 and 6 become collinear

The Chalmers University of Technology literature deals with these configurations in detail.

How to prevent the problem

Do the range analysis at the concept stage. Not at the end. Professional simulation software (DELMIA, RoboDK, Process Simulate) automatically highlights problem areas.

Rule of thumb: do not place any critical point more than 85% of its nominal radius.

For trajectories crossing singularities, you have three options:

1. Reorient the part towards the robot
2. Change the position of the robot base
3. Add an external axis (rotary table or linear guide)

The last option extends useful workspace. It is the most elegant solution for complex applications. But it increases the initial cost.

Range validation prior to installation avoids a common situation: the cell installed but unable to cover all working points. This is exactly the kind of problem we solve with our process simulation and validation services.

Mistake 3: underestimating the actual cycle time

In short: The simulation says 12 seconds. Reality says 18. A miscalculation jeopardizes the entire investment.

A 50% difference between simulation and reality is not unusual. It compromises the economic justification of any automation project. Investment calculated on optimistic figures no longer makes sense.

Where the errors come from

The sources are multiple and cumulative:

• Theoretical speeds, not real. The simulation uses maximum values. In continuous operation, robots slow down in sensitive areas and near setpoints.
• I/O times ignored. Confirmation between robot and PLC can add 100-200 ms per cycle. At 1000 cycles per shift, the difference becomes substantial.
• Imperfectly modeled motion merging. The real controller uses different algorithms than the simulator. The result can be more or sometimes less time.

How to prevent the problem

Use realistic parameters:

• Speeds at 80-85% of rated value
• 70-80% acceleration
• All sensor and gripper wait times
• Actuation times: opening, closing, vacuum pick-up, deposition

Validate the simulation against a prototype or similar existing cell. If you do not have a reference, add a margin of 15-20% over the simulated time in the cost-effectiveness calculation.

For projects with strict productivity requirements, analyzing bottlenecks makes all the difference. The article on the cost-effectiveness of robotic simulation through offline programming explains how to calculate the cost-benefit ratio correctly.

Pitfall 4: failure to fully validate collisions

In short: The simulator only detects what you invite it to check. The rest is a surprise on the first run.

Many cells are programmed without active detection on all relevant pairs. The problem has multiple overlapping layers.

What is most often ignored

The robot’s own collisions (with itself) are overlooked. “The robot has internal protections,” they say. Correct. But cables and hoses mounted externally on the arm have no such protections. They wear out quickly with aggressive movements.

Collisions between components are not automatically checked. They must be explicitly defined:

• Robot with fixture
• Robot with track
• Attachment device with conveyor
• Cell structure track

Safety zones are not modeled. Optical barriers, laser scanners, ATEX zones. The robot passes through them undetected in the simulation. At assembly, the safety system stops it in mid-motion.

How to prevent the problem

Define a complete collision matrix at the start of the project. Includes all relevant pairs.

Test the trajectory at incremental speeds. A collision that occurs only at full speed may be due to bending of the cables or recoil. These are phenomena that classical simulators do not model perfectly. Control Engineering has extensively documented these problems.

For high precision applications, elastic deformation analysis may be required. See our finite element analysis guide.

Full collision validation is the central argument for virtual commissioning. Visual Components describes how simulation becomes the foundation of digital planning.

Mistake 5: Incorrect calibration between simulation and reality

In short: The model can be perfect in CAD. Without proper calibration, the real robot misses the target by millimeters or even centimeters.

The phenomenon is known as the ‘reality gap’. It occurs between simulated and actual behavior. The causes are cumulative. Each contributes a fraction of the total error.

Why the gap appears

Robot manufacturing tolerances are a first factor. According to ISO 9283:2016, repeatability is less than 0.1 mm. But absolute accuracy (the ability to get to a programmed point) can exceed 1-2 mm.

Other sources of error:

• Robot base position. An error of 2 mm and 0.1° at the base is amplified at the tip of the tool, where it reaches 5-10 mm.
• Elastic deformations under load. The arm bends slightly. The simulator does not always model this effect.
• Thermal deviations. During a shift, the robot heats up. The geometry changes subtly.
• Mechanical wear over time. With each cycle, tolerances get wider.

How to prevent the problem

Implement the three-step calibration.

Step 1 – Tool Center Point Calibration (TCP). Use the 4- or 6-point method. Acceptable error:

• Less than 0.2 mm for welding
• Under 0.05 mm for precision assembly

The complete methodology is documented by RoboDK according to ISO 9283.

Step 2 – Calibrating the base and fixtures. Use a minimum of 3 reference points. Measure them physically with a laser tracker or coordinate measuring machine (CMM). Correlate the results with the CAD model. The wider the distribution, the more robust the calibration.

Step 3 – Advanced kinematic calibration. For high-precision applications, Denavit-Hartenberg parameter compensation reduces absolute errors by up to 80%. Justified for requirements below 0.5 mm.

Attention to one important detail. Each manufacturer (ABB, KUKA, FANUC, Yaskawa, ABB, KUKA, FANUC, Yaskawa) has its own particularities. The OLP postprocessor must be compatible with the exact firmware version. A mismatch here invalidates any calibration.

Best practices for successful offline programming

Beyond preventing the five mistakes, some general principles increase the success rate of PLO projects.

Document before the simulation. An inaccurate CAD model negates the benefits of any advanced software. A few extra hours at the start saves days on assembly.

Take an iterative approach. Don’t treat simulation as a one-off design stage. Come back to it after every major change. New parts, gripper upgrades, location changes. The real controller, the real parts, and the real cadence bring out things the simulator can’t anticipate.

Choose the right software. Each platform has its strengths:

• DELMIA – complex simulations, integration with enterprise PLM systems
• RoboDK – multi-brand flexibility, affordable licensing
• Visual Components – balance between performance and ease of use
• Process Simulate – solid alternative in Tecnomatix ecosystems

The decision depends on the volume of projects, cell complexity and the existing CAD ecosystem.

Standardize your workflow. From CAD import to download to the controller, every step needs clear procedures and checklists. Our structured process illustrates a disciplined approach.

Collaborate between teams. The offline programmer needs to understand what is physically happening in the cell. Field technicians need to know the assumptions in the simulation. The lack of this communication bridge is the source of many failures.

Use real data for calibration. Physical measurements with a laser tracker, CMM or at least a digital precision comparator. Never “by eye”. For stringent applications, ISO 9283:2016 provides the rigorous testing framework.

What’s next for your project

Offline programming is not a one-size-fits-all solution. It is a disciplined process. It rewards rigor and penalizes superficiality. Successful companies treat simulation as a strategic tool, not an automated configuration wizard.

Whether you’re planning a new robotic cell or optimizing an existing one, the Centerline team can support you every step of the way:

• Audit of existing cell and documentation by 3D scanning
• Virtual simulation and validation in DELMIA
• Final calibration and handover to production

Contact us for a technical discussion about your project.

For concrete examples of already implemented applications, case studies in our portfolio include high-speed cells for nut welding, automated cell upgrades and robotized cells for bearing welding.

The post 5 costly mistakes in offline programming of industrial robots and how to avoid them appeared first on CenterLine România.