ARTS IV is the fourth generation ARTS and was engineered for NASA DFRC’s F/A-18 #853 aircraft. The aircraft, recently dubbed the Full-scale Advanced Systems Testbed (FAST), is currently being flown in support of NASA’s Integrated Resilient Aircraft Controls (IRAC) project. The IRAC project will benefit aviation safety by creating technology that could help damaged aircraft to fly and land safely.
For the F-18 FAST aircraft, the WVHTC Foundation engineered, built, tested, and delivered:
- 3 Flight Units
- 4 Flight-Equivalent Laboratory Units
- 2 Portable Test Computers
Two flight units synchronized via an RS-422 cross-channel data link are installed on the FAST aircraft. The synchronized units provide a dual-redundant research flight computer system to host advanced research. The units are integrated with the FAST main flight computer via a quad-redundant 1553 bus. When the ARTS IV is engaged, the main flight computers allow it to have direct command authority over all of FAST’s control surfaces. The third flight unit serves as a spare.
For ARTS IV, the WVHTC Foundation developed and tested application software based upon requirements provided by NASA DFRC. The ARTS IV application software:
- Manages the quad-redundant communications with the aircraft flight computer via the 1553 bus
- Reads analog inputs from dedicated hardware
- Reads and writes discrete I/O from dedicated hardware
- Communicates with an embedded GPS/INS (EGI) via 1553 bus
- Votes, limit checks, and archives aircraft, EGI, discrete, analog and research data
- Monitors health and status of system/hardware/software
- Provides voted and checked data to research experiments
- Votes, limit checks, and sends research commands to the aircraft flight computer via the 1553 bus
- Verifies software and hardware integrity on power-up
- Manages system state and logs issues and problems for post-flight analysis
- Provides a protected region to facilitate the execution of untrusted research algorithms without concern for the safety critical software components
The ARTS IV application software reused concepts, architecture, and common subsystems from ARTS II and III. All safety-critical ARTS software is certified to NASA-STD-8719.13B, which is NASA’s standard for safety-critical software.
A single ARTS IV flight unit featured a ½ ATR flight chassis with three single board computers, and a wealth of external I/O including 1553B, Ethernet, RS-422, discrete, and analog. Additionally, each unit has 48 GB of on-board data storage capacity.
The ARTS IV flight units are environmentally certified to MIL-STD-810F (vibration, shock, and thermal) and MIL-STD-461E (EMI).
For more information on the FAST aircraft: https://www.nasa.gov/centers/dryden/news/X-Press/mrac.html