AXIOM Beta/Camera Structure
1 Camera Structure
“The hardware design of the AXIOM Beta was kept simple at first, purely addressing problems discovered with the AXIOM Alpha. In the beginning we had intended to design the camera around a single board on top of an off-the-shelf FPGA/system-on-chip development board: the MicroZed™, but as a result of field testing and together with feedback gathered from the community we agreed to make it far more powerful by devising a more complex stack of boards where each layer is dedicated to specific functions.” - Sebastian Pichelhofer.
2 AXIOM Beta PCB Stack Layout
Version 4:
Onshape CAD workfile here
Archive:
V03.02 - File:PCB Stack Concept V03 02.pdf
Note: All dimensions are not final. Work in progress...
3 Skeleton and Enclosure
The AXIOM beta Skeleton frame consists of the following components; Footplate, Skeleton, E-Mount lens tube and M3 threaded rods that hold the PCB Stack in place.
>>>> TODO include picture.
Skeleton and Skeleton Footplate: https://github.com/apertus-open-source-cinema/beta-hardware/tree/master/Enclosure/Skeleton_E-mount
Onshape PCB Stack and Skeleton Assembly: https://cad.onshape.com/documents/58bd498285673a104722aacd/w/466b8105bf6807b3f4f50b6c/e/b33cc7b3cc3cc5eebd5c2ae6
More enclosure options will follow but there are two versions currently available.
For enclosures (development pending) see - AXIOM_Beta/Enclosures
3.1 Mechanical Assembly
Skeleton and Footplate are attached to each other with 2x tapered M3x12 - M3x16 screws.
Nylon spacers, washers and nuts are used on the M3 threaded rods to hold the PCBs in the correct distances:
See Parts
4 Dimensions
| Height | Width | Length | Weight | |
|---|---|---|---|---|
| AXIOM Beta Skeleton Frame | 65.1mm | 111.76mm | 9mm | 47.9g |
| Enclosure Footplate | 45mm | 30mm | 8mm | 27.9g |
| E-mount Lens Tube | NA | 61mm diameter | NA | 28g |
| AXIOM Beta Developer Kit (board stack, footplate, lens tube & skeleton enclosure) | 65.1mm | 111.76mm | 74mm | 319g |
| AXIOM Beta Compact Enclosure | TBD | TBD | TBD | TBD |
5 Specifications
| AXIOM Beta Planned Hardware Specifications | |
|---|---|
| Image Sensor | CMV12000 (Used for research and development) |
| Lens Mount | Passive E-mount |
| Hardware Architecture | Xilinx Zynq 7020 based MicroZed |
| Modules and Shields | Single HDMI Full HD (4:4:4) output at up to 60 FPS |
| Dual 6G SDI output (in development) | |
| 3x PMOD debug module | |
| LED matrix debug module | |
| Genlock, Trigger, Timecode, LANC shields (in development) | |
| 4K Displayport/HDMI (in development) | |
| Connectivity | USB / USB UART / JTAG / Gigabit Ethernet |
| AXIOM Beta Software Features (some still in development) | |
|---|---|
| Operating System | Embedded Linux (Arch Linux) |
| Network Protocols | SSH/FTP/SCP/etc |
| Graphical User Interfaces via HTTP (in development) | |
| Capture | Global shutter Super 35 CMOS Image Sensor |
| Output | Uncompressed 4K raw (still images done, motion picture sequence currently in RGB 1060p60 max.) |
| Remote Control | Change/access all camera functions from smartphone, tablet, laptop (Web GUI (in development), Serial console, SSH) and AXIOM Remote (in development) |
| Power Management | Voltage, current, temperatures |
| Wide input voltage range (5-40V in development - currently works with 5V supply) | |
| Motion Tracking | 3D Accelerometer, 3D magnetometer and 3D gyroscope e.g. for image stabilization (in development) |
| Image Processing | Look-Up-Tables (LUTs) |
| Matrix color conversion | |
| Fixed Pattern Noise (FPN) compensation | |
| False color display | |
| Overlays | |
| Dead pixel compensation (in development) | |
| Connectivity | WiFi / Wireless adapters |
Note: As the AXIOM Beta is currently under heavy development some elements of the above table describe goals not the current state of development.
6 Main PCBs in Detail
The AXIOM Beta comprises five core printed circuit boards (PCBs):
- Sensor Board
- Sensor Interface Board
- AXIOM Beta Main Board
- AXIOM Beta Power Board
- Microzed
Different plugin modules and shields can be used to add interfaces or extend functionality.
In rare cases users may want to build the camera and or its components themselves - see AXIOM_Beta/Prices for cost estimates. We can either supply all the individual components or the relevant files with a view to a user sourcing unpopulated PCBs directly from the manufacturer. In any event make contact and we'll provide guidance.
| AXIOM Beta PCB's | ||
|---|---|---|
| Sensor Board | The Beta CMV12K ZIF Sensor Board hosts the heart of every cinema camera - the (CMOS) image sensor. apertus° offered three different sensor options during the crowd funding campaign; Super35, Super16 and 4/3rds, and as almost 90% of the backers opted for the Super35 sensor its respective module was developed first. The camera uses the ams Sensors Belgium CMV12000. Note: The ZIF (Zero insertion force) socket is useful for developers as it allows for the sensors removal at the turn of a lever (zero force). The AXIOM Beta Compact camera hosts the Beta CMV12K THT Sensor Board. THT (Through hole tech) is suited to applications where the sensor-front-end won't be removed regularly. | |
| Interface Board | The Beta Interface Dummy Board acts as a bridge between the image sensor board and the rest of the camera. It converts communication between the aforementioned components to a standard protocol so that almost any image sensor that becomes available in the future can be used with the AXIOM Beta without changing the rest of the hardware. If AXIOM users felt that 8K was in demand they would simply swap the sensor board for one capable of capturing images in the desired resolution. | |
| Beta Main Board | The Beta Main Board is the equivalent of a PC's motherboard. It hosts two external medium-speed shield connectors and two high-speed plugin module slot connectors. These act as a central switch for defining where data captured by the sensor and other interfaces gets routed to inside the hardware. In this regard, all specifics can be dynamically reconfigured in software opening up a lot of new possibilities such as adding shields for audio recording, genlock, timecode, remote control protocols or integrating new codecs and image processing inside the FPGA. In the centre of the main board a 'solder-on' area has been incorporated, this will for example host chips capable of sensing the camera's orientation and acceleration (the same chips used to stabilise quadcopters and track head movements in VR headsets). Being situated directly behind the image sensor centre means that these sensors are ideally positioned to supply data for image stabilisation or metadata about the camera’s orientation and movement during a shot. | |
| CSO |
The AXIOM Beta CSO (Center Solder On) is a small addon PCB that can be added to a pre-designated area on the Beta Main Board. It hosts chips capable of measuring and controlling compensation processes via the camera's software, i.e. for orientation and acceleration (the same chips used to stabilise quadcopters and track movement in VR headsets), magnetic field related data, and three dimensional motion sensing. | |
| Beta Power Board |
The Beta Power Board PCB generates all the different supply voltages for the chips and logic on the other PCB’s inside the camera. It also monitors currents so that it can estimate remaining power based on the recorded consumption. In the current revision of the camera a predefined set of supply voltages matching the current application with the rest of the camera have been generated, in the future however, it will be possible for users to dynamically reconfigure voltages according to their needs through the camera’s software. | |
| MicroZed |
The AES-Z7MB-7Z020-SOM-G MicroZed™ is a development board based on the Xilinx Zynq®-7000 All Programmable SoC (System-on-a-Chip). It can be used as both a stand-alone development board for SoC experimentation or in a product like the AXIOM Beta. | |
6.1 Associated Boards
| Asoociated PCBs | ||
|---|---|---|
| Power Adapter Board | The Beta Power Adapter Board connects the camera to a DC power supply via pico spox cable. | |
| Power Button Board | Presently in development - The Beta Power Button Board is applicable to the AXIOM Beta Compact (ABCP) and is a simple PCB featuring an LED to signify when the camera is active. | |
7 Plugin Modules and Shields
The AXIOM Beta has two high speed module slots with PCIe connectors (these are not really PCIe cards, we just utilize PCIe for the connectors). Each module has a total bandwidth to/from the main processing FPGA of at least 6 Gbit/s. This makes the modules perfect for dealing with high bandwidth video outputs like HDMI/Displayport/SDI.
Due to the flexibility that this arrangement provides this could also allow us to create a dedicated solid-state media recorder module in the future. For now the AXIOM Beta relies on external recording though.
7.1 Shields
The name shields was inspired by the Arduino plugin boards that are also called "shields". AXIOM Beta sports two shield slots with space for connectors going to both sides of the camera. In contrast to modules the shields in the Beta have slow and medium speed interfaces to the main processing FPGA, and, therefore, are perfect for tasks like: trigger IN/OUT, genlock IN/OUT, timecode IN/OUT, sync IN/OUT or connecting external sensors or buttons, LCDs, etc.
The AXIOM Beta has 2 medium speed IO interfaces to be used in conjunction with "shields".
- One 200Mbit/s (west) shield interface.
- One 1Gbit/s (east) shield interface.
Note: Shields are not hot plug-able.
| AXIOM Beta Shields | ||
|---|---|---|
| Debug Shield | The Beta Debug Shield 2x10 GPIO banks as LED indicators plus two power LEDs. 4 LVDS pairs routed to external connectors JP1/JP2 (plus one GND). | |
7.2 Plugin Modules
There are 2 high speed IO interfaces where "plugin modules" can be hot plugged. They feature:
- 6.2Gbit/s each:
- 6 ✕ 950Mbit/s
- 500MBit/s GPIO
- Two modules can be combined in one 12.4 Gbit/s double height module.
- Hot pluggable.
The plugin modules are PCIe x1 connectors which are not using PCIe signaling. The bottom Plugin Module is called "south" while the top is called "north".
| AXIOM Beta Plugin Modules | ||
|---|---|---|
| 1x PMOD Plugin Module |
The Beta 1x PMOD Plugin Module Single PMOD debug inputs/outputs for connecting a wide range of external PMOD devices - mainly intended for development and testing when General Purpose Input/Output (GPIO) is required. | |
| 3x PMOD Plugin Module |
The Beta 3x PMOD Plugin Module Triple PMOD debug inputs/outputs for connecting a wide range of external PMOD devices - mainly intended for development and testing when General Purpose Input/Output (GPIO) is required. | |
| PMOD LED Matrix Debug Module |
The PMOD LED Matrix Debug Module ... | |
| HDMI Plugin Module | The Beta HDMI Plugin Module The 1080p60 4:4:4 output HDMI module is finished, the AXIOM Beta can accommodate up to two of these plugin modules and supply them with independent video streams. | |
| 1x USB 3.0 Plugin Module (1x slot) | 1x USB 3.0 Plugin Module to allow storing of 4K uncompressed video to a connected PC. Offers 3.2 Gbit/s throughput which corresponds to 400MByte/s, enough to record uncompressed 4096x2160 raw 12 bit video at 25 FPS to a connected computer. | |
| Dual Riser Plugin Module |
The Dual Plugin Module Riser adds a 90° turn to the plugin module slots allowing them to be placed inwards on the AXIOM Beta. | |
| 4K HDMI Plugin Module |
The 4K HDMI Plugin Module Allows recording 4K/UHD video on an external recorder with a standard 2160p signal. Will also work to supply 4K/UHD screens with a signal of course. | |
| SDI Plugin Module (1x slot) |
The SDI Plugin Module An industry standard serial digital interface (SDI) connection plugin module will provide a nominal data transfer rate of 3G/6G. | |
Note: If no image or page exists in the above listings it's because the respective PCB is in development.
7.3 Plugin Module Pinout
| Pin Name | Function | Pin Name | Function |
|---|---|---|---|
| A1 | GND | B1 | I²C SDA |
| A2 | LVDS0 + | B2 | I²C SCL |
| A3 | LVDS0 - | B3 | VCC I²C (typically 3v3) |
| A4 | GND | B4 | IO 0 (typically 3v3) |
| A5 | LVDS1 + | B5 | IO 1 (typically 3v3) |
| A6 | LVDS1 - | B6 | IO 2 (typically 3v3) |
| A7 | GND | B7 | IO 3 (typically 3v3) |
| A8 | LVDS2 + | B8 | IO 4 (typically 3v3) |
| A9 | LVDS2 - | B9 | IO 5 (typically 3v3) |
| A10 | GND | B10 | IO 6 (typically 3v3) |
| A11 | Power Good; NC | B11 | IO 7 (typically 3v3) |
| A12 | GND | B12 | 5V |
| A13 | LVDS3 + | B13 | VCC (typically 3v3) |
| A14 | LVDS3 - | B14 | VCCIO LVDS (typically 2v4) |
| A15 | GND | B15 | GND |
| A16 | LVDS4 + | B16 | LVDS5 + |
| A17 | LVDS4 - | B17 | LVDS5 - |
| A18 | GND | B18 | GND |
8 Functions
Recording Options
The AXIOM Beta currently utilizes external third-party recorders for capturing moving images. A number of different products from different brands can record the HDMI signal from the AXIOM Beta and store the video in Prores or DNxHD. There are plans for enabling AXIOM Beta internal recording to solid state storage in the future however. In particular this is a requirement for writing high speed video as the Beta sensor is capable of capturing moving images at up to 300 FPS in full 4K resolution.
Operating System
Since the camera is running Linux, you have a full operating system at your disposal. This means any 3rd party peripherals like USB drives or wireless adapters should work out of the box. Standard protocols like SSH/FTP/SCP/etc. as well as Graphical User Interfaces via HTTP can be used to interface with the camera from computers and most mobile devices.
Sound
AXIOM Beta is not capable of recording sound internally at the moment.
How to Contribute - Growing and improving documentation is an ongoing process and you're very welcome to contribute to the project by helping to make these archives better for everyone.