Can FPGA and PLC Technology Make Radiation Therapy Better?
Radiation therapy is one of the foundations of cancer treatment, saving millions of lives annually. However, it faces significant challenges: high costs, limited adaptability, the need for precise targeting to minimise damage to healthy tissues, and complexity in system integration.
Field Programmable Gate Arrays (FPGAs) and Logic Controllers (PLCs) offer transformative solutions to the challenges, and their technology can be leveraged by hospitals, engineers, system integrators, and manufacturers of radiation therapy (RT) devices to create cheaper, smarter, and faster radiotherapy.
Background and Context
The need for affordable, effective cancer treatment is growing as more and more patients are diagnosed with cancer and seek accessible, top-notch care.
New approaches to radiation therapy—like particle therapy, flash therapy, real-time adaptive (RTA) treatment, and image-guided radiation therapy (IGRT)—highlight the urgent demand for creative, cutting-edge solutions.
However, most traditional RT systems often rely on expensive, rigid platforms that struggle to meet new demands, leading to high operational costs, limited adaptability, and integration challenges.
This blog explains how FPGA and PLC technologies, already long-established in PT/RT systems, continue to play a central role in enabling the next generation of real-time, safety-critical control systems for novel modalities such as FLASH and VHEE.
Understanding FPGA and PLC Technologies
Field Programmable Gate Arrays (FPGAs)
FPGAs are integrated circuits that can be programmed after they have been manufactured to perform specific functions, making them ideal for high-speed signal processing and data analysis. In radiation therapy, FPGAs excel in adaptive treatments, enabling real-time adjustments based on patient response.
They are particularly valuable for processing complex imaging tasks with minimal latency, such as those required in IGRT. This capability ensures precise targeting of tumours, limiting damage to healthy tissues and improving treatment outcomes.
A pivotal study [1] demonstrates FPGA’s strong points in medical imaging. Conducted in the context of IGRT systems for Interventional X-ray, the study highlights how FPGA accelerators handle high-resolution image processing under strict throughput constraints. The results showed significant improvements in throughput and latency, enabling real-time feedback during procedures, a critical requirement for adaptive RT systems.
Another study [2] further underscores FPGA’s potential by implementing a low-latency Multi-Layer Perceptron (MLP) processor on FPGAs, directly interfacing with sensors to minimise data movement delays and outperforming GPUs by a factor of 21, showcasing its ability to meet stringent timing requirements in real-time dose adjustments and imaging in RT.
Programmable Logic Controllers (PLCs)
Conversely, PLCs are digital computers built for industrial automation, providing dependable and adaptable systems control.
They can handle intricate workflows in radiation therapy, ensuring smooth coordination of elements such as patient positioning, accelerators, and dose delivery systems. Their reliability reduces system downtime and operational risks, while their flexibility allows customisation to specific clinical needs, improving efficiency and patient throughput.
Modern applications of PLCs in radiotherapy extend beyond basic coordination to include advanced features such as VMAT/ARC-based delivery support. This entails trajectory optimisation that enables the fastest possible treatment delivery within subunits’ mechanical and dynamic constraints, like gantry and couch rotation or multileaf collimators (MLCs).
Through synchronous control of all relevant units, PLCs ensure that these systems accurately follow the planned trajectory, critical for complex dose sculpting in VMAT.
Moreover, a PLC-based solution enables a seamless delivery path execution, tightly integrating motion control, gating signals, and dose rate modulation in real-time. These systems also support delivery flow control features, such as pausing for gating or movement synchronisation, and ensure comprehensive session data logging for later analysis, traceability, and audit.
Importantly, robust error handling is integrated to safeguard patient safety, ensuring that any fault or deviation from the prescribed path triggers appropriate mitigation protocols.
A compelling example of a PLC application is an automation system developed for a COVID-19 testing facility [3] that processed over 100,000 samples daily with PLCs to control transport systems and work cells. This setup increased throughput, reduced human error, and ensured traceability, principles directly applicable to RT workflows where precision and reliability are paramount.
PLCs are widely used in pharmaceutical manufacturing to ensure consistent quality and regulatory compliance.
A research paper on PLC automation in packaging lines highlights their role in controlling machines to reduce contamination risks and meet FDA requirements and GAMP5 standards [5].
Benefits of FPGA and PLC in RT Control Systems and Integration
The integration of FPGA and PLC technologies creates a powerful synergy for RT control systems, as has been proven in related fields.
FPGAs handle high-speed, data-intensive operations like real-time imaging and dose calculations, while PLCs ensure reliable system coordination and automation..
While direct RT cost comparisons are limited, industrial PLC implementations suggest significant savings through efficiency and reduced downtime, while FPGA’s offer cost savings through hardware reuse and reconfigurability, making them ideal for evolving RT technologies.
Below are these benefits in detail, supported by third-party case studies and research.
Cost Optimisation
Traditional RT systems rely on expensive, dedicated real-time platforms, driving up both initial and maintenance costs. Although there are few direct cost comparisons for RT systems, industrial PLC use shows clear savings through improved efficiency and reduced downtime [4].
Similarly, optimised FPGA designs cut hardware needs, reducing development and upkeep costs.
Enhanced Real-Time Responsiveness
When adapting to patient movement or tumour changes, real-time responsiveness is crucial in RT.
FPGAs offer ultra-low latency, as shown in a neural network study [2] with 144× speed increase over CPUs, thus enabling faster dose calculations and imaging adjustments for greater precision. PLCs complement this by reliably managing workflows like positioning and beam delivery, minimising treatment delays.
Improved Precision and Patient Safety
Precision is critical in RT to target tumours while protecting healthy tissue.
FPGAs enable this through real-time high-resolution image processing and adaptive dose delivery, essential for IGRT systems [1].
PLCs add precision by reliably controlling subsystems like accelerators and positioning, meeting strict quality standards and improving safety [5].
Seamless System Integration
RT system integration is complex, requiring coordination across imaging, accelerators, and delivery. FPGAs and PLCs simplify this with flexible, interoperable solutions. FPGAs interface directly with sensors and processing pipelines [2], while PLCs use standardised protocols to ensure seamless component synchronisation.
Simulation and test automation
In Proton and Radiation Therapy (PT/RT), simulation and test automation are vital for validating safety, timing, and control logic. At Cosylab, we use our expertise in FPGA and Beckhoff PLC platforms to deliver robust and testable control solutions tailored to medical environments.
Using Beckhoff’s TwinCAT ecosystem, Cosylab applies tools like TCUnit for structured PLC unit testing, TwinCAT Scope for real-time signal tracing, and TwinCAT Plastic for modular code versioning.
We use tools like NCI (Numerical Control Interface) for motion systems to simulate complex, multi-axis movements, which is ideal for rapid prototyping patient positioning, gantry, and couch workflows.
FPGAs complement PLCs by enabling ultra-fast simulation of real-time operations such as beam feedback and dose control and their deterministic execution and integration with co-simulation tools like MATLAB/Simulink supports hardware-level validation under clinical constraints.
Together, these platforms form a powerful test environment aligned with IEC 60601-1, IEC 62304, and IEC 62366, supporting safe, efficient, and standards-compliant RT system development.
Reduced Downtime and Increased Throughput
In radiation therapy (RT), system downtime disrupts patient schedules and limits treatment capacity. PLCs minimise downtime through reliable, deterministic control of safety-critical and operational subsystems.
In parallel, FPGAs enhance throughput by accelerating real-time data processing tasks—such as imaging, motion feedback, and dose regulation—enabling faster, more efficient treatment delivery.
Customizability and Scalability
Effective RT systems must evolve with clinical and technological advancements.
FPGAs offer unmatched customizability, allowing hardware-level programming to meet specialised imaging, gating, or dosimetry requirements, which is particularly valuable in advanced modalities like proton therapy.
PLCs provide scalable architectures, supporting modular upgrades and seamless integration of new subsystems, such as imaging units or motion controllers. Together, they ensure long-term adaptability and investment protection.
Regulatory Compliance and Market Readiness
Regulatory compliance is critical for RT devices, with standards like ISO 13485 and IEC 62304 governing development. FPGA and PLC technologies, widely used in regulated industries, facilitate compliance and are market-ready, accelerating time-to-market for manufacturers.
Feature Comparison: FPGA and PLC vs. Conventional Approaches
We present two comparison tables to highlight the distinct strengths and trade-offs of FPGA and PLC technologies compared to conventional real-time (RT) system architectures.
The first table focuses on common engineering challenges and how each approach addresses them; the second emphasises core technical attributes.
Table 1: Solutions & Benefits
| Challenge | FPGA and PLC Technology | Conventional Technology for RT Systems |
| High Costs | Long-term cost efficiency through hardware reuse (FPGAs) and modular I/O expansion (PLCs); higher initial development effort | May incur higher upfront costs for commercial RTOS licenses or specialised real-time hardware, but benefit from lower development overhead |
| Limited Adaptability | FPGAs offer reconfigurable logic; PLCs allow modular expansion and programmable logic changes | RTOS-based systems support high adaptability at the software level, but lack hardware-level reconfigurability |
| Precision Targeting | FPGAs enable ultra-low-latency, hardware-timed adaptive control; PLCs offer deterministic but slower cycle-based control | RTOS-based systems support adaptive control with flexible software, but may be limited by OS jitter and execution delay |
| System Integration Complexity | PLCs support standard industrial protocols with strong vendor support; FPGA integration can be efficient but requires hardware/software co-design | Software-based systems integrate well with modern IT stacks but may need more middleware and abstraction to connect with hardware interfaces |
Table 2: Technical Features
| Feature | FPGA and PLC Technology | Conventional Technology for RT Systems |
| Processing Speed | FPGAs enable high-throughput, parallel execution for time-critical logic; PLCs operate with moderate scan-cycle speeds | CPUs in RTOS-based systems process tasks sequentially or multicore; efficient but not suitable for extreme real-time acceleration |
| Reliability | PLCs are robust and proven in industrial environments; FPGAs reduce risks by avoiding OS layers | Reliable under well-tested software and RTOS, but more exposed to software faults and race conditions |
| Customizability | FPGAs offer deep, low-level hardware customizability; PLCs allow functional configuration via modular logic blocks | High software-level customizability via APIs and modular code; limited hardware-level flexibility |
| Latency | FPGAs offer ultra-low latency through parallel, hardware-timed execution; PLCs provide moderate latency |
Typically higher latency due to sequential execution and OS overhead; may impact responsiveness
|
Conclusion
The radiotherapy market is undoubtedly evolving ever faster, with increasing demand for affordable, precise, and efficient solutions.
Regulatory trends, such as stricter compliance requirements, and technological advancements, like AI, proton therapy and image-guided irradiation, are driving innovation.
Cosylab’s OncologyOne is a modular suite of medical-grade software functionalities for controlling RT devices, including LINACs, particle therapy and BNCT systems, fully incorporating FPGA and PLC technology.
With Cosylab’s OncologyOne, clinics, engineering teams, system integrators and manufacturers can fulfil their ambitions of modernising RT sooner.
Key Citations:
- [1] Modeling and Analysis of FPGA Accelerators for Real-Time Streaming Video Processing (https://link.springer.com/article/10.1007/s11265-018-1414-3)
https://link.springer.com/article/10.1007/s11265-018-1414-3]
- [2] Real-time Data Analysis for Medical Diagnosis Using FPGA-Accelerated Neural Networks
https://pubmed.ncbi.nlm.nih.gov/30577751/
- [3] Automation System for Ginkgo’s Latest Testing Facility
https://www.dmcinfo.com/latest-thinking/case-studies/view/id/565/automation-system-for-ginkgos-latest-testing-facility
- [4] PLC Usage in the Pharmaceutical Industry https://www.plctalk.net/threads/plc-usage-in-the-pharmaceutical-industry.1595/
- [5] PLC in Pharmaceutical Industry
https://amd-digitalhub.com/industries/plc-in-pharmaceutical-industry/
About the author
Primož Napotnik leads a team focused on development and test automation for PLC and FPGA platforms in safety-critical systems. The team automates to a level that frees them up for high-impact work—and occasionally for well-earned fun time.