R&D PULSE
Wrapping Cables to Optimize Performance
A model that identifies the best way to wrap cables around a spacecraft’s structural components minimizes their impacts on performance.
Written by Mark Crawford
MUCH OF THE INNOVATION in aerospace is driven by advances in materials science, especially improved stiffness-to-weight ratios of structural components. However, counteracting those lighter-weight improvements is an increase in cable use, driven by growing demands for data and power transmission.
“As a result, accurately incorporating the effects of cable dynamics into the modeling of these structures has become crucial,” said Armaghan Salehian, associate professor of mechanical and mechatronics engineering at the University of Waterloo in Canada.
Considering cables can account for nearly one-third of spacecraft weight, detailed modeling of their stiffness and damping is of great importance to future aerospace design—therefore it is critical to have accurate lightweight space structural models, especially for control algorithms.
In an effort to enhance the modeling techniques for cable-harnessed structures, Salehian, Momoiyioluwa Oluyemi, a mechanical engineering graduate student at Waterloo, and Pranav Agrawal, a postdoctoral fellow at the University of California, Los Angeles, conducted extensive research to develop analytical models for these structures, resulting in partial differential equations (PDEs) of vibrations that will enhance spacecraft performance.
“The idea of exploring wrapping patterns as a way to minimize cable dynamic impacts on payload structures is quite inspiring,” Salehian said. “Our study provides proof-of-concept for the mathematical modeling techniques we developed for the ideal cable placement to preserve the dynamic properties of the host plate structures.”
An LMS SCADAS mobile sits on top of a vibrometer controller. Photo: Armaghan Salehian/University of Waterloo
Methodology and Approach
The key goal of mathematical modeling of cable-harnessed structures is to better understand the complex dynamics resulting from cable interactions with the host structure. Salehian’s team hoped it could optimize cable placement and identify ideal wrapping configurations to reduce the dynamic effect of the cables, which were harnessed to plate structures in two periodic wrapping patterns—zigzag and diagonal.
Four thin cable-harnessed plate structures were tested. The cables were wrapped around the plates in a way that resulted in multiple, repeated fundamental elements. The wrapping angle θ was measured with respect to the wrapping direction, which was in the direction of the x-axis or the y-axis.
The team used an energy-equivalence homogenization approach to derive PDEs that govern bending vibrations of cable-harnessed plate structures. “This involved determining the kinetic and strain energy of the repeating fundamental elements, which yielded an equivalent continuum structure, with dynamic characteristics similar to that of a cable-harnessed structure,” said Oluyemi.
“Mimicking the real load conditions in a space environment including the micro-vibrations that are generally experienced in orbit, as well as investigating similar geometries to payload structures, were some of the biggest challenges we faced in this research,” said Salehian.
The experimental setup consisted of:
- Experimental modal impact testing, using an impulse force hammer to excite the structure.
- Capture of the structure’s response using a laser vibrometer operated via a vibrometer controller.
- Using transducer data from the actuation and sensing measurements, computed experimental Frequency Response Functions (FRFs) for the plate structures with and without cables, for comparison to assess cable dynamics on each plate.
By assuming a periodic cable wrapping pattern, the cable-harnessed structure was modeled using repeating fundamental elements. “This periodicity enabled the application of the energy-equivalence homogenization method, leading to the partial differential equations that describe the out-of-plane vibrations of the cable-harnessed plate systems,” Oluyemi said.
A Few Surprises
The team’s results showed that the tested structures exhibited minor changes in dynamic properties when harnessed with the cables. This demonstrates that cables can be wrapped around a host plate-like structure and have minimal impact to its dynamics, identifying specific wrapping geometries to achieve this. “The insights provided by these findings could simplify modeling and vibration control of cable-harnessed plate-like structures by potentially allowing engineers to ignore cable effects on the host structure,” Salehian said. “This advancement is particularly valuable for space applications and other engineering fields involving cable harnessing on plate-like structures.”
One of the biggest surprises was the unexpected observation that the best performing patterns were not always the most intuitive ones. “Some of the optimal configurations appeared unconventional when compared to the symmetrical layouts that are typically used,” Agrawal said. “This result demonstrated that the design space for cable-harnessed structures is more complex than what rule-of-thumb approaches usually capture.”
Another surprise was the effectiveness of the computational optimization framework. It was able to identify high-performing cable layouts that exceeded the performance of manually designed configurations. “This finding suggests that wrapping patterns, which are often treated as a secondary detail in deployable and aerospace structures, can in fact serve as a highly tunable design variable,” said Agrawal.
Mechanical engineers will be especially interested in how the team addressed a critical challenge in modern mechanical design: how to integrate cabling—a necessary component in many modern mechanical structures—without compromising the host structure’s dynamic performance. “Our research offers practical methodologies for minimizing the unintended stiffness and inertia effects introduced by cable harnesses, which can significantly alter natural frequencies, mode shapes, and overall system dynamic behavior,” Oluyemi explained.
Mechanical engineers working in aerospace, automotive, robotics, or precision instrumentation will find this study to be particularly relevant, as these fields often involve lightweight, flexible structures where dynamic integrity is paramount. “The insights from this work can inform design guidelines, modeling practices, and system integration strategies, ultimately supporting the development of more reliable and high-performance mechanical systems,” Oluyemi said.
An electrochemical biosensor quickly measures one of the decomposition compounds. Photo: Armaghan Salehian/University of Waterloo
Schematics of the cable-harnessed plate structure with (a) zigzag and (b) diagonal wrapping patterns. The solid lines represent the segments of the cables on the top surface of the plate while the dashed lines represent the parts on the bottom surface. The wrapping is in the x-direction. Images: Armaghan Salehian/University of Waterloo
Future Work and Broader Impact
The team’s work offers substantial scope for future development. Plate-like structures represent only a narrow subset of the diverse structural forms encountered in engineering applications. The next phase involves extending the modeling framework to encompass a broader range of structural geometries, “enabling the identification of optimal cable placement strategies tailored to each,” Oluyemi said.
Moving forward, the team has developed a model for cable-harnessed circular cylindrical shell structures with axially aligned cables. Once experimentally validated, this model will serve as a foundation for exploring alternative cable configurations and their dynamic implications—leading to innovative designs for cable layouts that minimize their dynamic effects on cylindrical shell-like host structures.
The research has strong potential beyond space structures because the idea of using optimized cable patterns to tune stiffness, damping, and impact behavior is relevant in many fields that rely on lightweight or flexible components. “In robotics, for example, cable routing is a common way to actuate soft mechanisms, and our approach could help reduce unwanted vibrations during rapid movements,” Agrawal said. “In the automotive and protective equipment sectors, cable-reinforced panels are used for energy absorption, and optimized patterns could improve their ability to manage impacts without adding extra weight.”
Mark Crawford is a technology writer in Corrales, N.M.
© 2026 The American Society of Mechanical Engineers. All rights reserved.