## Tools
- 3D printer (PETG and ABS capable)
- Hex key set (M2, M2.5, M3, M4, M6)
- Precision screwdriver set (Phillips, Flathead)
- Multimeter
- Wire strippers and crimpers
- Soldering iron (fine and general tips)
- Solder (lead-free recommended)
- Heat gun (for heat shrink)
- Drill press or hand drill
- Tap set (M2, M2.5, M3, M4, M6)
- Deburring tool
- Isopropyl alcohol and lint-free cloths
- Thermal paste applicator/spreader
- Thermal epoxy applicator
- Adhesive applicator (for sensors and gaskets)
- Torque wrench (for structural bolts)
- Small pliers/tweezers

## Assumptions
- Builder has basic electronics assembly and soldering experience
- Builder is familiar with 3D printer operation and filament handling
- Builder has access to a bench power supply (24V/12V) for testing
- Builder has basic Linux command-line knowledge for OS and driver installation
- All necessary cables (power, data, internal, external) are pre-cut and pre-terminated where applicable, or builder has crimping/soldering skills to create them

## 1. Fabrication
### 1.1 3D Print all custom mounting brackets and enclosures
**3D print all custom mounting brackets and enclosures.**
1. Print the HSM Daughterboard Mount (PETG, 30% infill, 0.2mm layer), Audit SSD Mount (PETG, 20% infill, 0.2mm layer), ML SSD Mount (PETG, 20% infill, 0.2mm layer), GPS/PPS Module Mount (PETG, 25% infill, 0.2mm layer), BMS Mounting Plate (PETG, 20% infill, 0.2mm layer), Fan 1, 2, and 3 Mounting Frames (PETG, 20% infill, 0.2mm layer each), GPIO Isolate MOSFET Enclosure (PETG, 20% infill, 0.2mm layer), Ethernet Switch Enclosure (PETG, 20% infill, 0.2mm layer), UART Transceiver Enclosure (PETG, 20% infill, 0.2mm layer), NXP EdgeLock SE051 Secure Element Mount (PETG, 30% infill, 0.2mm layer, 4 perimeters), all 6 Internal Temperature Sensor Mounts (PETG, 30% infill, 0.2mm layer, 4 perimeters each), and the Internal Power/Active Status LED Mounts (PETG, 30% infill, 0.2mm layer, 4 perimeters each).
2. Print Peltier Mount 1 and Peltier Mount 2 using ABS filament with 100% infill and 0.2mm layer height.
3. Inspect all 3D printed parts for accuracy, layer adhesion, and any printing defects. Remove supports and clean up any stringing or imperfections.
4. Test fit components into their respective mounts (e.g., SSDs into Audit/ML SSD Mounts, secure element into its mount). Trim or file as needed for a snug fit.
5. Ensure all screw holes are clear and correctly sized for M2 or M2.5 fasteners as specified in the mechanical connections. Tap holes if required, especially for ABS parts.

### 1.2 Prepare aluminum structural components (drill, tap, deburr)
**Prepare aluminum structural components by drilling, tapping, and deburring.**
1. Mark and drill mounting holes for M4 machine screws on the Internal Aluminum Sub-frame to attach to the Main Shell, and for M3 standoffs and M4 screws for the Kria/Jetson Carrier Mounting Plates and Power Conditioning Tray respectively.
2. Mark and drill holes for M4 machine screws on the Thermal Exchanger Plate for mounting to the Main Shell, ensuring proper sealing surfaces are maintained.
3. Drill and tap M3 holes on the Rear, Front, and Side A Connector Panels for EMI gasketed mounting to the Main Shell.
4. Drill and tap M6 holes on the NATO Rail Mount Base, Tripod Adapter Base, and all four Fixed Mount Corner Brackets for secure attachment to the Main Shell.
5. Carefully deburr all drilled and tapped holes on all aluminum components to remove sharp edges and ensure a smooth finish, critical for EMI sealing and preventing wire damage.

### 1.3 Install recessed handles and EMI gaskets on enclosure
**Install recessed handles and EMI gaskets onto the main enclosure shell.**
1. Clean and prepare the mounting surfaces on the Enclosure Main Shell for both Recessed Side Handles (Left and Right).
2. Position the Recessed Side Handle (Left) onto its designated location on the Enclosure Main Shell and secure it using M6 bolts.
3. Repeat the process for the Recessed Side Handle (Right), securing it with M6 bolts.
4. Apply the NEMA 4X Gasket Set along all mating surfaces and seams of the Enclosure Main Shell, ensuring a continuous and compression-sealed barrier.
  > Tip: Ensure all mounting holes for the handles are sealed with appropriate sealant during installation to maintain the NEMA 4X rating and EMI integrity.

### 1.4 Brazing/Epoxy cooling fins to thermal exchanger plate
**Brazing or epoxying cooling fins to the aluminum thermal exchanger plate.**
1. Thoroughly clean the contact surfaces of the Cooling Fin Array and the Thermal Exchanger Plate with isopropyl alcohol to remove all oils and debris.
2. Choose your joining method: for brazing, apply appropriate aluminum brazing flux; for thermal epoxy, apply a thin, even layer of high-temperature thermal epoxy.
3. Carefully align and press the Cooling Fin Array onto the designated area of the Thermal Exchanger Plate.
4. If brazing, use an oxy-acetylene torch or induction heating to evenly heat the joint until the brazing material flows to form a complete bond. If epoxying, clamp the assembly and allow the thermal epoxy to cure according to manufacturer specifications.
5. Inspect the joint for full coverage and mechanical integrity, ensuring a robust thermal pathway.
  > Tip: For optimal thermal performance and ruggedness, brazing is preferred over epoxy. If using thermal epoxy, select one with high thermal conductivity and mechanical strength suitable for MIL-STD-810G environments.

### 1.5 Assemble battery compartment frame with door
**Assemble the hot-swap battery compartment frame and door.**
1. Secure the Battery Compartment Frame to the Enclosure Main Shell using the integrated chassis mounts and appropriate M4 machine screws.
2. Attach the Hot-Swap Battery Door to the Battery Compartment Frame using its designated hinges, ensuring smooth opening and closing motion.
3. Confirm that the latching mechanism on the Hot-Swap Battery Door securely engages with both the Battery Compartment Frame and the Enclosure Main Shell.
4. Verify that the NEMA 4X EMI gasket forms a complete and tight seal around the perimeter of the Hot-Swap Battery Door when closed.
  > Tip: Proper alignment of the battery compartment and door is crucial for maintaining environmental sealing and EMI integrity, as well as ensuring smooth hot-swap operation.

## 2. Wiring
### 2.1 Solder TPM and Secure Element to their daughterboards/mounts
**Solder the TPM and Secure Element to their respective daughterboards.**
1. Carefully position the Infineon SLB 9670 TPM 2.0 Module onto its designated pads on the HSM Daughterboard (not the 3D-printed mount, but the PCB that fits into it).
2. Solder all pins of the Infineon SLB 9670 TPM 2.0 Module to the HSM Daughterboard, ensuring clean solder joints and no bridges.
3. Place the NXP EdgeLock SE051 Secure Element onto its PCB footprint on its dedicated adapter board that fits into the NXP EdgeLock SE051 Secure Element Mount.
4. Solder the I2C and Power pins of the NXP EdgeLock SE051 Secure Element to its adapter board, maintaining precise alignment and quality solder joints.
5. Conduct a visual inspection of all solder joints on both modules for continuity and absence of shorts or cold joints.
  > Tip: Utilize a temperature-controlled soldering iron with a fine tip and appropriate flux for precision soldering of small module pins to avoid damage and ensure reliable connections.

### 2.2 Wire all DC-DC converters and TVS network into power conditioning tray
**Wire all DC-DC converters and TVS network into power conditioning tray.**
1. Mount the SiC TVS Network onto the Power Conditioning Tray, ensuring clear access to Input and Protected Output terminals.
2. Connect the positive and negative inputs from the External Connector J1 (Vehicle DC Input) to the 'Input +' and 'Input -' pins of the SiC TVS Network.
3. Connect the 'Protected Output +' and 'Protected Output -' pins of the SiC TVS Network to the main 28V/12-24V input of the Main DC-DC Converter (28V/12V/AC to 24V).
4. Mount the Main DC-DC Converter (28V/12V/AC to 24V), DC-DC Converter (24V to 12V), DC-DC Converter (24V to 5V), and DC-DC Converter (24V to 3.3V) to the Power Conditioning Tray.
5. Wire the 24V output of the Main DC-DC Converter to the input of the 24V to 12V DC-DC Converter, 24V to 5V DC-DC Converter, and 24V to 3.3V DC-DC Converter respectively, using appropriately gauged and insulated wires.
  > Tip: Ensure all power connections are robust, crimped, and soldered for high reliability, and use heat shrink tubing to insulate exposed terminals.

### 2.3 Connect Battery Management System (BMS) to battery pack and power conditioning system
**Connect the Battery Management System to the LiFePO4 battery pack and power conditioning system.**
1. Secure the Battery Management System onto the BMS Mounting Plate using M2.5 screws.
2. Connect the Power Output + and Power Output - terminals of the 280 Wh LiFePO4 Battery Pack to the 'Pack Input' terminals of the Battery Management System.
3. Wire the 'Load Output' terminals of the Battery Management System to the battery input section of the Main DC-DC Converter (28V/12V/AC to 24V) on the Power Conditioning Tray, ensuring polarity is correct.
4. Connect any Cell Balancer Inputs from the 280 Wh LiFePO4 Battery Pack to the corresponding inputs on the Battery Management System as per the BMS manufacturer's instructions.
  > Tip: Double-check all battery and BMS connections for correct polarity before applying power to prevent damage to components and ensure safety. Use crimped and soldered connections for high current paths.

### 2.4 Prepare internal wiring harnesses for power and data distribution
**Prepare and assemble internal power and data wiring harnesses.**
1. Fabricate 24V power harnesses for Peltier Elements, fans, and Jetson Power Isolation MOSFET input from the main 24V bus and 12V output. Use appropriate gauge wire, crimp terminals securely, and apply heat shrink tubing for insulation.
2. Create 5V power harnesses for the 10GBASE-T Ethernet Switch, UART Transceiver, and both Internal Status LEDs. Solder or crimp connections as needed, ensuring proper polarity and insulation.
3. Prepare 3.3V power harnesses for all six Internal Temperature Sensors. Solder tiny wires to the sensor boards, ensuring reliable connections for power and ground.
4. Construct data harnesses for the Ethernet Switch to both Kria and Jetson carrier boards using appropriate Ethernet cable and connectors.
5. Build UART data harnesses for the Kria Carrier Board to the UART Transceiver (TX/RX) and the Jetson Carrier Board to the UART Transceiver (TX/RX). Label each end clearly.
6. Assemble I2C data harnesses for the Kria Carrier Board to all six Internal Temperature Sensors, paying attention to SCL/SDA lines and wire lengths for signal integrity.
7. Create the GPIO control wire from the Kria Carrier Board's FPGA_GPIO_ISOLATE pin to the Gate pin of the Jetson Power Isolation MOSFET.
8. Label all fabricated harnesses clearly on both ends to identify their source and destination components.

### 2.5 Integrate GPS/PPS receiver with antenna connector wiring
**Wire GPS/PPS receiver to its antenna connector.**
1. Connect the RF Signal pin of the External Connector J12 (GPS/PPS Antenna SMA) to the 'Antenna' pin of the GPS/PPS Receiver Module using a suitable SMA to U.FL (or equivalent) coaxial cable.
2. Ensure the coaxial cable is properly routed and secured to prevent strain on the connectors.
3. Verify the ground connection of the coaxial cable is solid to ensure proper RF shielding for the GPS/PPS Receiver Module.
4. Mount the GPS/PPS Receiver Module onto its dedicated GPS/PPS Module Mount using M2.5 screws, ensuring its antenna connection is strain-free.

### 2.6 Mount and wire all external connectors to their respective panels
**Mount and wire all external connectors to their respective panels.**
1. Mount the External Connector J1 (Vehicle DC Input) onto the Rear Connector Panel using its threaded bulkhead mounting, securing with the J1 DC Input Mount.
2. Mount the External Connector J2 (AC Input) onto the Rear Connector Panel and secure it with the IEC C14 Retaining Clip, using the J2 AC Input Mount for alignment.
3. Mount the External Connector J12 (GPS/PPS Antenna SMA) onto the Rear Connector Panel using its threaded bulkhead mounting, securing with the J12 GPS Antenna Mount.
4. Wire Pin 1 (+28V/12-24V) and Pin 2 (GND) of External Connector J1 to the Input + and Input - pins of the SiC TVS Network respectively, ensuring robust connections for high current.
5. Wire the Line, Neutral, and Ground pins of External Connector J2 to the appropriate input terminals of the Main DC-DC Converter (28V/12V/AC to 24V).
6. Mount External Connector J3 (Radar Ethernet), J4 (RF SDR USB 3.0), J5 (EO/IR USB 3.0 + MIPI), J6 (ADS-B/RID UART), and J7 (LIDAR Ethernet) onto the Sensor Ingress Panel (Side A) using their respective threaded bulkhead mountings (J3, J4, J5, J6, J7 Mounts).
7. Connect the Ethernet data lines of External Connector J3 to the Internal 10GBASE-T Ethernet Switch and External Connector J7 to the Internal 10GBASE-T Ethernet Switch using appropriate shielded Cat6 cables.
8. Connect the USB 3.0 VBUS, GND, D+, and D- pins of External Connector J4 and J5 to the corresponding USB 3.0 ports on the Jetson AGX Orin Carrier Board.
9. Connect the MIPI Data Lanes and Clock of External Connector J5 to the MIPI CSI-2 input on the Jetson AGX Orin Carrier Board.
10. Connect the UART TX, RX, GND, and VCC (3.3V) pins of External Connector J6 to the UART port on the Kria KR260 Carrier Board, and the VCC (3.3V) to the DC-DC Converter (24V to 3.3V).
11. Mount External Connector J8 (Operator Console Ethernet), J9 (Federal-Tier Secure Relay Ethernet), J10 (External Audit Anchor Ethernet), and J11 (Maintenance Service USB-C) onto the Front Connector Panel using their respective threaded bulkhead mountings (J8, J9, J10, J11 Mounts).
12. Connect the Ethernet data lines of External Connector J8, J9, and J10 to the Internal 10GBASE-T Ethernet Switch using appropriate shielded Cat6 cables.
13. Connect the USB-C data lanes, VBUS, and GND of External Connector J11 to the USB port on the Kria KR260 Carrier Board.
  > Tip: Proper strain relief for all external cables is critical for MIL-STD-810G compliance and long-term reliability. Use cable glands and clamps where appropriate.

## 3. Bring-up
### 3.1 Perform initial power-on and voltage verification for all power rails
**Verify power rail voltages from DC-DC converters and TVS network.**
1. Connect a calibrated multimeter to the 'Protected Output +' and 'Protected Output -' pins of the SiC TVS Network.
2. Apply power to the system via the External Connector J1 (Vehicle DC Input) or External Connector J2 (AC Input) and verify that the voltage at the TVS Network outputs is stable and within expected input range (28V or 12-24V).
3. Relocate the multimeter to the 'Output +' and 'Output -' pins of the Main DC-DC Converter (28V/12V/AC to 24V) and confirm a stable 24V output.
4. Measure the outputs of the DC-DC Converter (24V to 12V), DC-DC Converter (24V to 5V), and DC-DC Converter (24V to 3.3V) respectively, ensuring they provide clean 12V, 5V, and 3.3V.
5. Verify the 24V output from the Battery Management System's 'Load Output' when operating from battery power, ensuring proper voltage and current handling.

### 3.2 Install OS and base firmware on Kria K26 SOM (Governance Plane)
**Install OS and base firmware on Kria K26 SOM.**
1. Securely insert the Kria K26 SOM into the SOM Connector on the Kria KR260 Carrier Board.
2. Connect a serial console cable to the UART port on the Kria KR260 Carrier Board (typically J2 or J4, check board documentation) and a host PC for boot monitoring.
3. Prepare a microSD card with the appropriate Yocto Linux or PetaLinux image for the Kria K26 SOM, following Xilinx documentation for image flashing.
4. Insert the prepared microSD card into the microSD slot on the Kria KR260 Carrier Board.
5. Apply 12V power to the Kria KR260 Carrier Board and observe the boot sequence and initial firmware loading messages via the connected serial console.
6. Verify successful operating system boot and initial functionality, including basic network connectivity if configured.
  > Tip: Ensure the correct boot mode (e.g., SD card boot) is selected via any DIP switches on the Kria KR260 Carrier Board prior to applying power to ensure the SOM attempts to boot from the prepared media.

### 3.3 Install OS and base firmware on Jetson AGX Orin SOM (ML/Fusion Plane)
**Install OS and base firmware on Jetson AGX Orin SOM.**
1. Securely insert the Jetson AGX Orin SOM into the SOM Connector on the Jetson AGX Orin Carrier Board.
2. Connect a USB-C cable from the Jetson AGX Orin Carrier Board's debug port to a host PC.
3. Place the Jetson AGX Orin Carrier Board into Recovery Mode (usually by holding down Force Recovery button, then Reset button, then releasing Reset, then Force Recovery).
4. Use the NVIDIA SDK Manager on the host PC to flash the JetPack OS and base firmware onto the Jetson AGX Orin SOM.
5. After flashing, connect a display to the DisplayPort and apply 12V power to the Jetson AGX Orin Carrier Board to verify successful boot into the operating system GUI.
6. Perform initial setup steps including user account creation and network configuration.

### 3.4 Verify communication with TPM and Secure Element via SPI/I2C
**Verify SPI/I2C communication with TPM and Secure Element from Kria.**
1. Ensure the Kria KR260 Carrier Board is powered on and running its Linux OS with SPI and I2C kernel modules loaded.
2. Access the Kria's command line interface (via serial console or SSH).
3. To verify the Infineon SLB 9670 TPM 2.0 Module (SPI), execute appropriate TPM discovery commands (e.g., `tpm2_getcap -c properties-fixed`, `ls -l /dev/tpm*`) to confirm the TPM device is enumerated and responsive.
4. To verify the NXP EdgeLock SE051 Secure Element (I2C), run an I2C bus scan (e.g., `i2cdetect -y <bus_number>`) to detect the secure element's I2C address, typically 0x48 or 0x49.
5. Attempt a basic read/write operation or status check on the NXP EdgeLock SE051 Secure Element using appropriate I2C utilities or SDK commands to confirm data communication.

### 3.4a One-time cryptographic provisioning (air-gapped, pre-integration)
**Provision TPM 2.0 and Secure Element key material on an air-gapped workstation BEFORE the Kria SOM and HSM daughterboard are integrated into the main chassis.**
1. Stage the Kria K26C SOM with the HSM daughterboard (TPM + SE) on an isolated bench workstation with no network connectivity.
2. Generate the ECDSA P-256 sensor-input signing keypair inside the Infineon SLB 9670 TPM 2.0 using `tpm2_createprimary` followed by `tpm2_create` and `tpm2_evictcontrol` to make the key persistent. Record the public key fingerprint for the deployment manifest.
3. Generate the audit-ledger root signing keypair (separate ECDSA P-256 key) using the same procedure with a distinct persistent handle.
4. Provision the NXP EdgeLock SE051 secure element with operator credential keys and the federal-tier handoff key material per the deployment's credential roster.
5. Export the public key bundle to a removable medium for distribution to verifier endpoints. The private keys NEVER leave the TPM or SE.
6. Sign a provisioning attestation containing the SOM serial, TPM public key fingerprint, ledger root public key fingerprint, SE credential set identifier, UTC timestamp, and technician identifier. Append the attestation to the provisioning ledger.
7. Power-cycle the SOM and verify that all keys remain accessible by handle. Only then is the SOM ready for chassis integration in Step 4.2.
  > Tip: The provisioning workstation must be air-gapped. Key material generation on a networked workstation invalidates the deployment's evidence-chain foundation for Federal Rules of Evidence 901, 902, and 803(6).


### 3.5 Test Ethernet switch and internal 10GBASE-T links
**Verify internal 10GBASE-T Ethernet switch and links between compute planes.**
1. Ensure both the Kria KR260 Carrier Board and Jetson AGX Orin Carrier Board are powered on and their respective operating systems are running.
2. Confirm the Internal 10GBASE-T Ethernet Switch has power and its status LEDs indicate operational status for all connected ports.
3. From the Kria's operating system, verify network interface detection and link status for its 10G Ethernet Port connected to the Internal 10GBASE-T Ethernet Switch.
4. From the Jetson's operating system, verify network interface detection and link status for its 10G Ethernet Port connected to the Internal 10GBASE-T Ethernet Switch.
5. Perform a ping test or a small file transfer between the Kria and the Jetson over the 10GBASE-T Ethernet link, verifying data connectivity and expected throughput.

### 3.6 Calibrate and verify temperature sensor readings across various locations
**Calibrate and verify all internal temperature sensor readings.**
1. Ensure the Kria KR260 Carrier Board is powered on and running its operating system with I2C drivers for the Analog Devices ADT7320 (or similar) temperature sensors loaded.
2. Access the Kria's command line interface (via serial console or SSH).
3. Utilize I2C tools (e.g., `i2cdetect -y 1`, `i2cget`, or a custom Python script) to read temperature values from each of the six Internal Temperature Sensors connected to Kria Carrier Board's I2C1 bus.
4. Compare the readings from each Internal Temperature Sensor against a known, calibrated reference thermometer placed near the respective sensor locations. Record any observed discrepancies.
5. If necessary, apply software calibration offsets within the Kria's operating system or sensor driver configuration to adjust the reported temperatures to match the reference thermometer.

### 3.7 Test Peltier modules and fans for cooling functionality and control
**Test Peltier modules and fans for cooling control and functionality.**
1. Ensure the Kria KR260 Carrier Board is powered on and its operating system is running, with necessary GPIO/PWM drivers for Peltier control and fan speed activated.
2. From the Kria's command line, send a low power command to Peltier Element 1 (e.g., via GPIO controlling a MOSFET or dedicated driver), observing if it begins to cool on one side and heat on the other using a calibrated temperature sensor or by touch.
3. Gradually increase the power to Peltier Element 1 and verify a corresponding change in cooling/heating performance, monitoring with local temperature sensors.
4. Repeat the power control and monitoring process for Peltier Element 2.
5. Activate Sealed Intake Fan 1 from the Kria (e.g., via PWM control), confirming that it spins up and produces airflow; vary its speed and observe the change in RPM/airflow.
6. Repeat fan activation and speed control for Sealed Intake Fan 2 and Sealed Intake Fan 3, ensuring all fans are operational and responsive to control signals from the Kria.
  > Tip: Begin Peltier testing at low power levels to prevent thermal shock or overheating of the hot side before the cooling system (fans/heat pipes) is fully engaged. Monitor power consumption during full load to ensure it stays within specifications.

### 3.8 Validate GPS/PPS receiver functionality and timing synchronization
**Validate GPS/PPS receiver functionality and timing synchronization.**
1. Connect an active GPS antenna to the External Connector J12 (GPS/PPS Antenna SMA) on the BLADE-CUAS unit.
2. Ensure the Kria KR260 Carrier Board is powered on and its operating system is running, with the UART driver for the GPS/PPS Receiver Module enabled.
3. From the Kria's command line, monitor the UART port receiving NMEA data from the GPS/PPS Receiver Module (e.g., `cat /dev/ttyS0` or equivalent) to confirm valid NMEA sentences are received and a GPS fix is acquired.
4. Configure a GPIO pin on the Kria KR260 Carrier Board as an input to receive the PPS (Pulse Per Second) signal from the GPS/PPS Receiver Module, and monitor for a stable 1Hz pulse (e.g., using `gpiomon` or a custom application).
5. Verify that the Kria's system clock is synchronized to the GPS PPS signal using NTP or PTP configured to use the PPS input, checking the clock drift and offset to confirm deterministic timing.
  > Tip: Position the GPS antenna with a clear view of the sky to ensure optimal satellite acquisition and a strong PPS signal. Check the GPS module's status LED for a valid fix indication.

## 4. Assembly
### 4.1 Mount internal aluminum sub-frame into the main enclosure
**Mount the internal aluminum sub-frame securely into the main enclosure.**
1. Carefully lower the Internal Aluminum Sub-frame into the Enclosure Main Shell, ensuring proper alignment with the pre-drilled mounting holes.
2. Insert M4 machine screws through the designated holes in the Internal Aluminum Sub-frame and into the corresponding threaded inserts or nuts on the Enclosure Main Shell.
3. Hand-tighten all M4 machine screws initially, then systematically tighten them in a star pattern or alternating sequence to ensure even pressure and prevent warping.
4. Verify that the Internal Aluminum Sub-frame is firmly secured within the Enclosure Main Shell and does not show any rotational or translational play.
  > Tip: Use a torque-limiting screwdriver to ensure consistent and appropriate tightening of the M4 machine screws, preventing overtightening which could damage threads or deform components.

### 4.2 Integrate Governance and ML carrier boards with SOMs, SSDs, and heatsinks onto their mounts
**Integrate Kria and Jetson compute modules, SSDs, and heatsinks onto their mounting plates.**
1. Securely insert the Kria K26 SOM into its connector on the Kria KR260 Carrier Board.
2. Apply Graphite TIM Kria to the Kria K26 SOM and then attach the Kria Heatsink, ensuring even pressure for optimal thermal contact.
3. Mount the Audit Ledger SSD into the Audit SSD Mount and then secure this assembly to the Kria Carrier Mounting Plate using M2.5 screws.
4. Mount the Kria KR260 Carrier Board assembly onto the Kria Carrier Mounting Plate using M3 standoffs and screws.
5. Securely insert the Jetson AGX Orin SOM into its connector on the Jetson AGX Orin Carrier Board.
6. Apply Graphite TIM Jetson to the Jetson AGX Orin SOM and then attach the Jetson Active Heatsink, ensuring proper contact and secure fastening.
7. Mount the ML Model/Frame Cache NVMe SSD into the ML SSD Mount and then secure this assembly to the Jetson Orin Carrier Mounting Plate using M2.5 screws.
8. Mount the Jetson AGX Orin Carrier Board assembly onto the Jetson Orin Carrier Mounting Plate using M3 standoffs and screws.
9. Finally, mount both the Kria Carrier Mounting Plate and the Jetson Orin Carrier Mounting Plate assemblies to the Internal Aluminum Sub-frame using M3 standoffs and screws.
  > Tip: When mounting heatsinks, follow the manufacturer's recommended torque specifications to ensure proper thermal contact without damaging the semiconductor package.

### 4.3 Install the power conditioning tray and battery management system into the sub-frame
**Install the power conditioning tray and battery management system assemblies into the sub-frame.**
1. Secure the Power Conditioning Tray to the Internal Aluminum Sub-frame using M4 screws, ensuring it is firmly mounted in its designated location.
2. Mount the Battery Compartment Frame, which should already house the Battery Management System, to the Internal Aluminum Sub-frame using its integrated chassis mounts and M4 machine screws.
  > Tip: Ensure adequate clearance for wiring and thermal management around the power conditioning components and battery system before final tightening. Refer to spatial layout for optimal placement.

### 4.4 Secure thermal exchanger plate, Peltiers, heat pipes, and cooling fans
**Secure all thermal management components: plate, Peltiers, heat pipes, and cooling fans.**
1. Mount the Thermal Exchanger Plate to the Enclosure Main Shell using M4 machine screws, ensuring a sealed connection to maintain environmental integrity.
2. Apply a thin, even layer of thermal epoxy to one side of Peltier Element 1 and Peltier Element 2. Secure each Peltier Element into its respective Peltier Mount (Peltier Mount 1, Peltier Mount 2), then attach these assemblies to the Thermal Exchanger Plate using M2 screws, ensuring adequate compression.
3. Install the Heat Pipe Array by fitting it onto the Thermal Exchanger Plate, making sure to use thermal compound between contact surfaces for efficient heat transfer, and secure with compression fittings if applicable.
4. Mount Sealed Intake Fan 1, Fan 2, and Fan 3 into their respective Fan Mounting Frames (Fan 1 Mounting Frame, Fan 2 Mounting Frame, Fan 3 Mounting Frame) using M3 screws.
5. Attach each Fan Mounting Frame assembly to the Enclosure Main Shell using M3 screws, aligning them with the cooling fin array.
6. Secure the Air Filter Grille 1, Air Filter Grille 2, and Air Filter Grille 3 to the exterior of the Enclosure Main Shell, ensuring they snap-fit or screw into place over their corresponding fans and are retained by the fan mounts for easy maintenance.

### 4.5 Route and secure all internal power and data cabling, ensuring strain relief
**Route and secure all internal power and data cabling with strain relief.**
1. Connect the 12V output from the DC-DC Converter (24V to 12V) to the Kria KR260 Carrier Board and the input of the Jetson Power Isolation MOSFET.
2. Wire the protected 12V output from the Jetson Power Isolation MOSFET to the Jetson AGX Orin Carrier Board.
3. Connect the 5V output from the DC-DC Converter (24V to 5V) to the Internal 10GBASE-T Ethernet Switch, UART Transceiver (Kria-Jetson), Internal Power Status LED, and Internal Active Status LED.
4. Connect the 3.3V output from the DC-DC Converter (24V to 3.3V) to the Infineon SLB 9670 TPM 2.0 Module, NXP EdgeLock SE051 Secure Element, GPS/PPS Receiver Module, and all six Internal Temperature Sensors (1-6).
5. Route Ethernet cables between the Kria KR260 Carrier Board and the Internal 10GBASE-T Ethernet Switch, and between the Jetson AGX Orin Carrier Board and the Internal 10GBASE-T Ethernet Switch.
6. Connect the UART TX/RX lines between the Kria KR260 Carrier Board and the UART Transceiver, and between the Jetson AGX Orin Carrier Board and the UART Transceiver.
7. Connect I2C data lines from the Kria KR260 Carrier Board to the NXP EdgeLock SE051 Secure Element and all Internal Temperature Sensors (1-6).
8. Connect SPI data lines from the Kria KR260 Carrier Board to the Infineon SLB 9670 TPM 2.0 Module.
9. Connect PCIe M.2 SSDs (Audit Ledger SSD and ML Model/Frame Cache NVMe SSD) to their respective carrier boards.
10. Wire the 24V output from the Main DC-DC Converter (28V/12V/AC to 24V) to Peltier Element 1, Peltier Element 2, Sealed Intake Fan 1, Sealed Intake Fan 2, and Sealed Intake Fan 3.
11. Route all external connector cables (J1-J12) from their bulkhead connections to their internal destinations, utilizing cable ties and adhesive clips to secure them to the Internal Aluminum Sub-frame and prevent movement or abrasion.
12. Apply appropriate strain relief to all cable connections, especially at points of entry/exit from components and at bulkhead connectors, to prevent dislodgement under vibration or shock.

### 4.6 Mount external mounting options (NATO rail, tripod, fixed brackets) and apply dust caps
**Mount external mounting options and apply dust caps to connectors.**
1. Mount the NATO Rail Mount Base to the bottom of the Enclosure Main Shell using M6 machine screws.
2. Mount the Tripod Adapter Base to the bottom of the Enclosure Main Shell, ensuring it is positioned as specified, using M6 machine screws.
3. Attach each of the four Fixed Mount Corner Brackets (1-4) to their designated corner locations on the Enclosure Main Shell using M6 machine screws.
4. Securely attach the Dust Cap for J1, J3, J4, J5, J6, J7, J8, J9, J10, J11, and J12 to their respective external connectors. Ensure each dust cap's lanyard is properly secured to prevent loss during operation.

### 4.7 Install LiFePO4 battery pack and close battery compartment
**Install LiFePO4 battery pack and close battery compartment.**
1. Carefully slide the 280 Wh LiFePO4 Battery Pack into the Battery Compartment Frame, ensuring the BMS Communication and Power Output pins align with the pre-wired connections.
2. Connect the battery's BMS communication cable and power output cables to the Battery Management System's corresponding ports, ensuring secure and correct polarity connections.
3. Close the Hot-Swap Battery Door, ensuring it aligns correctly with the Battery Compartment Frame and the Enclosure Main Shell.
4. Engage the latching mechanism on the Hot-Swap Battery Door to securely fasten it. Verify the door is fully closed and the NEMA 4X gasket is properly compressed for environmental sealing.
  > Tip: Always ensure the battery pack is inserted with correct orientation and connections to prevent damage to the BMS or the battery. Double-check latches for full engagement to maintain environmental integrity.

### 4.8 Perform final system test and close enclosure
**Perform a final system test and securely close the enclosure.**
1. Conduct a comprehensive functional test of all integrated subsystems (power, compute, communications, sensors, thermal management) to ensure full operational capability and compliance with design specifications.
2. Verify that the Internal Power Status LED and Internal Active Status LED are clearly visible and functioning correctly through the Status LED Transparent Window on the front panel.
3. Carefully align the top cover of the Enclosure Main Shell with the main body, ensuring all internal components and cabling are clear of pinch points.
4. Secure the Enclosure Main Shell by tightening all M4 machine screws around the perimeter. Use a calibrated torque driver to ensure consistent pressure and optimal NEMA 4X gasket compression.
5. Conduct a leak test (e.g., low-pressure air leak test) to confirm the NEMA 4X sealing integrity of the closed enclosure.
  > Tip: Proper torque application during enclosure closure is critical to maintain environmental sealing (NEMA 4X) and EMI/EMC shielding. Over-tightening can damage gaskets or fasteners, while under-tightening compromises protection.
