Custom FlexRIO Adaptor Module supports HIL Test Upgrade
A custom-COTS approach reduces cost and delivery time.
Client – Major National Research Lab
Our client has a client (the end-user) for which they developed an HIL test system several years prior. Parts were obsolete and the system needed an upgrade. The prior system had many custom-designed electronic components which could not be replaced without a complete redesign.
Consequently, our client wanted to use COTS. However, one device needed 28 VDC digital I/O, a couple of lines which carried significant current (amp, not milliamp, levels) and at switching rates much higher than a COTS solid state relay could provide.
Viewpoint reviewed the requirements and created a hybrid COTS-custom solution. We combined an NI FlexRIO module with a custom FlexRIO Adapter Module (FAM) for the front end to satisfy the 28 VDC signals levels and required current drive.
- COTS FlexRIO integrates into the remainder of our client’s PXI-based test system.
- The Custom I/O was designed for flexibility. Our client can use this FAM for both their initial end-user and other programs / clients too.
- Reduced cost relative to a completely custom solution.
- Delivery time reduced by months relative to a custom solution
The custom FAM interfaced with the NI FlexRIO module, which offered low-level digital I/O (3.3 V logic), to digital signal conditioning hardware that provided the 28 VDC signal levels and required current drive.
Each I/O pin was configurable as input or output (source or sink). Each bank of 4 channels had an adjustable threshold level set via an adjustable DAC output. Some of the channels are designed for amp-level current drive, while the remainder were 250 mA. All I/O was fused appropriately.
Viewpoint also developed LabVIEW FPGA and VHDL to enable our client and the end-user to:
- Configure the I/O as in or out.
- Communicate to the DAC to allow custom input threshold trigger levels.
- Read and write the digital data.
|Set the direction of each of the DIO channels|
|Set the threshold level on the input channels|
|Read / Write DIO Data|
|End User Application|
|COTS NI FlexRIO|
|Custom FlexRIO Adaptor Module(FAM)|
|INTERFACES / PROTOCOLS|
|Customized VHDL Component Level Intellectual Property (CLIP) integrated with LabVIEW FPGA|
|LabVIEW FPGA as required along with LabVIEW and TestStand|