Test Jigs for TestBot:Bridging Physical Layer of Automation

As embedded systems grow increasingly complex—incorporating a range of analog, digital, communication, and mechanical interfaces—automated testing has become a necessity rather than a luxury.

Understanding these evolving needs, we developed TestBot, a powerful and flexible automated testing framework built specifically for embedded product validation.

While much focus is given to software-driven automation, true validation of embedded systems often requires interacting with the physical hardware—simulating inputs, measuring outputs, toggling real-world signals, and interpreting human-machine interfaces. This is where Test Jigs come into play.

In this blog, we’ll dive deep into the concept of Test Jigs in TestBot, list the different jigs supported by the platform, and show how they enable real-world hardware-in-the-loop (HIL) automation with precision, repeatability, and scale.

What Is a Test Jig in TestBot?

A Test Jig in the TestBot ecosystem is a hardware fixture or tool, often electronic or electro-mechanical, that facilitates automated interaction with the Device Under Test (DUT). It may simulate signals, control interfaces, apply loads, capture outputs, or even interpret visual displays.

Test Jigs are not mandatory for all tests but become essential when:

• Real-world inputs need to be simulated (e.g., analog voltages, button presses)
• Output signals need to be captured or measured (e.g., PWM waveforms)
• Mechanical or HMI interactions need to be automated
• Precision analog values such as resistance must be applied

These jigs work alongside TestBot Agents to execute the complete test workflow.

Why Use Test Jigs?

The use of test jigs ensures:

• Repeatability – Consistent test results across cycles and units
• Speed – Accelerated test execution compared to manual probing
• Coverage – Full access to electrical and mechanical interfaces
• Safety – Isolated and safe stimulus injection
• Scalability – Parallel testing using multiple jigs

With the help of TestBot’s modular architecture, test jigs can be optionally added to a test setup and customized based on the application.

Supported Test Jigs in TestBot

Here’s a comprehensive list of Test Jigs currently supported in the TestBot ecosystem, along with their key capabilities and target applications.

1. Automotive I/O Test Jig

Key Features:

• Simulates Digital Inputs (e.g., ignition, sensor triggers)
• Reads Digital Outputs (e.g., relays, indicators)
• Applies Analog Inputs (e.g., throttle voltage)
• Reads Analog Outputs (e.g., sensor outputs)
• Generates PWM Outputs to test pulse detection
• Supports testing of steering wheel switches, rotary knobs, and stalk controls

Applications:

• ECU functional testing
• Body Control Module (BCM) validation
• Instrument cluster input/output simulation
• Automotive switch testing and analog interface simulation

2. Digital Decade Resistance Box Test Jig

Key Features:

• Programmatically sets resistance values between 0.1 ohm and 99,999 ohms
• High precision with digital control
• Emulates sensor outputs like thermistors (NTC/PTC), position sensors, etc.

Applications:

• Sensor simulation in medical and automotive domains
• Resistance-based input validation
• Thermistor input simulation for temperature sensing ECUs

3. XY Manipulator Test Jig

Key Features:

• 2-axis robotic arm for linear motion
• Precise positioning on a defined X-Y grid
• Used to press capacitive/resistive touch buttons or activate mechanical inputs

Applications:

• Panel switch testing
• Automated front panel interface validation
• User interaction simulation for industrial HMIs and control panels

4. SCARA Manipulator Test Jig

Key Features:

• Articulated robotic arm for multi-directional motion
• Can mimic complex hand gestures or button presses
• Integrates with TestBot for motion control, timing, and pressure simulation

Applications:

• End-of-Line (EOL) testing of automotive ECUs with physical buttons
• Automated mechanical switch validation
• User interface testing involving complex interaction patterns

5. HMI Digitizer Test Jig

Key Features:

• Equipped with a high-resolution camera
• Captures display contents from LCDs, OLEDs, or HMIs
• Applies OCR (Optical Character Recognition) or image comparison to interpret visual outputs

Applications:

• Display content verification
• Automated HMI validation
• Dashboard and instrument cluster output testing

Custom Test Jigs in TestBot

No two embedded products are the same—and neither are their testing requirements.

That’s why TestBot supports the integration of custom Test Jigs, purpose-built for customer-specific DUTs. Embien Technologies offers consultation and development services to design jigs tailored to your:

• Connector layouts
• Signal conditioning needs
• Mechanical interfaces
• Environmental test requirements (e.g., temperature, vibration)

Custom test jigs can be easily plugged into the TestBot framework using standardized I/O interfaces, relay control boards, or microcontroller-based control modules. They integrate seamlessly with TestBot Agents, enabling test scripts to control and communicate with the jigs in real-time.

How Test Jigs Fit into the TestBot Workflow

Here’s how a typical TestBot test case using a jig works:

1. Test case execution starts on the TestBot server
2. The test case calls a TestBot Agent (e.g., Analog IO Agent)
3. The agent sends a command to the Test Jig (e.g., apply 2.5V to analog input)
4. The jig interfaces physically with the DUT
5. The DUT responds, and the response is read by another agent or jig
6. The results are logged and displayed in TestBot’s report

This architecture abstracts complex hardware interactions behind clean software APIs, allowing test developers to focus on test logic, not hardware quirks.

Conclusion

Test Jigs are a vital component of TestBot’s automated testing ecosystem, providing the physical interface needed to validate embedded hardware under real-world conditions. Whether it’s applying analog voltages, toggling GPIOs, mimicking user interactions, or interpreting displays, Test Jigs make it possible to perform complete hardware-in-the-loop (HIL) testing with speed, precision, and reliability.

With a growing list of prebuilt jigs—and the ability to design custom jigs for unique applications—TestBot enables companies to automate even the most intricate embedded validation workflows.

At TestBot, we’re committed to making embedded testing smarter, faster, and more accessible. TestBot, with its modular agents and flexible jigs, is helping QA teams around the world move confidently from prototype to production.