Dev Report 03:
Chain Elongation and Cam Validation in the Digital Twin
The third dev report covers a mechanical effect that is often underestimated in real-world systems: chain elongation. In practice, a chain never behaves ideally. It changes over time, positions shift, and the timing can deviate from the planned sequence. Precisely these deviations can become critical in motion control applications, electronic cams, and cycle-dependent movements. With NexaTwin Mechanic Validation, our goal is to make such effects visible not just on the real machine. The aim is to simulate and evaluate chain elongation in the digital twin and make it usable for subsequent real-world adjustments.
Why Chain Elongation Is Critical in Real Systems
In the ideal simulation, mechanical components behave exactly as they were designed. In a real system, however, this is not the case. Chains stretch, cam positions shift, and clearances change. This can lead to a situation where a previously correct cam profile no longer fits cleanly under real mechanical conditions. Motion sequences fall out of timing, transfers shift, or positions no longer match the expected logic. This is precisely why it is important to identify mechanical deviations early on.
What's currently being created in NexaTwin
A key focus of the current development is the adjustable chain elongation within the NexaTwin Mechanic Validation. The aim is to demonstrate how an elongated chain affects kinematics, cam positions, and cam validation.
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- adjustable maximum chain elongation in percent
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- Live change via a slider
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- visible kinematic effects in the digital twin
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- visual feedback on chain elongation and visibility of cam lobe spacing
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- Display of cam position changes
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- Basis for later actual cam settings
Change chain stretch live and make it visible
For the simulation, a maximum chain elongation can be defined. This allows mapping how much a chain is allowed to stretch or has already stretched in real operation. At runtime, the chain elongation can be changed between normal state and maximum elongation. A slider directly visualizes how the kinematics, chain position, and cam position change. This transforms an abstract mechanical effect into a comprehensible digital scenario.
Color Feedback for Chain Status
To quickly assess the current state of the chain, chain elongation is visually represented in NexaTwin. Green indicates no or minimal elongation, yellow indicates moderate elongation, and red indicates maximum elongation. This color-coded feedback helps to directly classify the mechanical condition. Users do not merely have to interpret numerical values but can immediately see the range of chain elongation. This supports review, training, and technical evaluation in the digital twin.
Checking Cam Positions and Cam Distances
Not only chain elongation itself is particularly important, but also its concrete influence on cam positions and cam distances. When a chain elongates, positions shift. This changes distances and can cause movements to deviate from the planned timing. NexaTwin is designed to make these position changes visible. This makes it possible to understand how mechanical elongation affects the entire movement sequence. This makes cam validation more realistic, as it does not only consider ideal cam profiles.
Why Cam Profiles Need Realistic Mechanics
Predefined cam profiles only function correctly in practice if the mechanical conditions are suitable. A profile may appear correct in an ideal model, but lose accuracy under real conditions due to chain elongation, position shifts, or altered cam distances. This is precisely where the benefit of a digital mechanic validation comes in. The digital twin not only shows the planned motion sequence, but also makes visible how mechanical deviations influence this sequence. This allows cam profiles to be tested under more realistic conditions.
What the NexaTwin Chain Simulation Aims to Support
The NexaTwin Chain Simulation aims to help better understand the difference between an ideal model and a real plant. This involves not only visualization, but also technical evaluation and preparation of real settings.
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- Early detection of mechanical chain stretch
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- Clearly display cam position changes
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- Validate cam profile under more realistic conditions
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- make percentage elongation usable for later real settings
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- Better understanding of discrepancies between ideal model and real plant
NexaTwin as a Tool for Mechanical Validation
With chain elongation simulation, NexaTwin is further developing towards practical mechanical validation. It's not just about representing ideal movements, but about making real mechanical effects understandable and assessable. This is particularly relevant for motion control, electronic cams, chain simulation, virtual commissioning, and drive technology.
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- Mechanical Engineering and Drive Technology
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- Motion control applications
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- Virtual Commissioning
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- PLC and PLC-related automation
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- Cam Validation
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- Chain simulation and technical validation prior to the real machine
Conclusion: Visualizing real mechanical effects in the Digital Twin
Chain elongation is a good example of why a digital twin must do more than represent ideal movements. In real systems, mechanical conditions change. These changes influence positions, distances, timing, and thus the validity of cam profiles. With NexaTwin Chain Simulation, we want to make precisely these relationships visible. Chain elongation, cam positions, and cam validation become traceable in the digital twin and can later serve as the basis for real machine settings. This makes NexaTwin a tool that supports technical relationships from digital validation to the real machine.