Material testing machines require precise and reliable control systems to ensure accurate force, displacement, strain, and other measurements. Selecting the right controller is essential for achieving repeatability, compliance with testing standards, and smooth automation. With multiple options available, from modular platforms like NI cRIO to specialized controllers like DOLI and MTS, choosing the right solution depends on factors such as machine type, flexibility required, real-time control capabilities, and integration with sensors and actuators.

In this post, we’ll compare several controllers used in material testing applications: ADMET, Beckhoff, B&R, Moog, MTS, NI sbRIO/cRIO, TACTUN, and Zwick/Roell – DOLI, highlighting their strengths, limitations, and best-use scenarios.

Key Factors to Consider When Choosing a Controller

Before selecting a controller for your material testing machine, it is essential to evaluate key factors that determine its suitability for your specific application. A controller in a material testing machine typically serves as both the data acquisition (DAQ) and control system, managing test execution while simultaneously recording sensor data. Choosing the right system ensures precise, repeatable, and compliant test results while also allowing for flexibility in automation and integration.

Key considerations include:

• Real-Time Control & Performance – The controller must provide deterministic, low-latency closed-loop control for precise force, displacement, or strain regulation. Evaluate the achievable control frequency and loop rate based on your actuator type (servo-electric, servo-hydraulic, etc.). A stable real-time environment ensures repeatable test results across all your machine models.
• System Architecture & Scalability – A good controller should allow you to build a scalable product line rather than one-off machines. Consider whether the platform supports multiple I/O configurations, modular extensions, or software reusability across your models. Scalable architecture reduces R&D cost for future machine variants.
• I/O Density and Sensor Interfaces – Machine builders often integrate multiple load cells, extensometers, and environmental sensors. Check that the controller offers sufficient analog and digital I/O channels with high-resolution ADCs and built-in signal conditioning options (e.g., strain gauge, LVDT, encoder). This minimizes external boards and simplifies wiring.
• Software Environment & Development Workflow – The programming model defines your engineering effort and update speed. Decide whether you want a low-code or graphical environment (for faster prototyping) or a fully programmable platform (for deep customization). Also assess version control, debugging, and simulation tools for in-house development.
• Integration & Time to Market – Controllers vary in integration complexity. Some require extensive software and electrical engineering, while others come with pre-built libraries for common test functions (PID control, ramp profiles, data logging). Evaluate how quickly your team can integrate the system into a new machine and start production.
• Compliance and Calibration Frameworks – Machine builders must ensure that their machines can be calibrated and validated according to ASTM, ISO, and EN standards. The controller should provide calibration routines, traceable data acquisition, and the ability to document compliance for end-customers.
• Cost of Ownership & Supply Chain Stability – Beyond unit price, consider engineering time, firmware maintenance, and vendor dependency. A stable controller partner with long-term component availability ensures continuity of your machine production.

Understanding these factors will help determine whether a programmable modular platform like NI sbRIO/cRIO or a dedicated testing controller like DOLI or MTS is the right fit for a specific application. In the following sections, we compare eight leading controller solutions used in material testing

Note, next sections are ordered alphabetically.