User:TwisteR
| General info | |
|---|---|
| Name | Anton Dubniak |
| Occupation | Electronics engineer, embedded developer |
| Experience | Overall 8 years of professional experience in hardware and software development |
| Foreign Language Skills | English - written: upper-intermediate, spoken: intermediate |
| Location | Kyiv, Ukraine |
| Hobby | Free and open-source software and hardware, astronomy, cosmology |
| Contact details | |
tfsoft at online.ua
| |
| IRC | tfsoft.org.ua:6667/#main
|
| Public key fingerprint | 0x4A8802E3192D15CE60BF99AE18A195EF8E9D778B
|
| Public key | Download |
| Personal qualities | |
| Work | High commitment to work and rooting for project's outcome |
| Communication | Preference in writing dialogue |
| Expectations from the next project | |
| Scope | Science, R&D, industrial automation |
| Type | Substantial and meaningful, with diverse and challenging tasks |
CV
Electronics design
- Digital circuits: discrete logic, microcontrollers (AVR, nRF5x), SoC (i.MX6/8)
- Basic analog design (signal amplification/attenuation, filters, op-amp circuits, output power stages, inductive and capacitive load management)
- Mixed signal design (DAC/ADC)
- Design of printed circuit boards, including HDI designs and RF signal integrity
- Design for manufacture, organization of mass-production
- Parametric modeling (device enclosures, part drawings, etc)
- Development of technical requirements specification, preparation of design documentation
Software skills
- C, C++, shell scripting, basic Python
- Profiling, coverage analysis, unit-testing
- Experience in debugging and profiling of complex asynchronous real-time systems
- Advanced development practices: test and packaging automation, continuous integration, reproducible builds (binary level identity)
- Cross-compilation, emulation
- Free and open-source software (task-specific modifications, support, interaction with authors and maintainers)
- Data visualization and visual representation of task-specific processes: UI/UX/HMI design, development of interactive SCADA diagrams
- Multimedia conversion and processing, experience in streaming media, strong background in FFmpeg (both libraries and application)
- Development of special purpose GNU/Linux distributions (based on Gentoo, Yocto Project, OpenWrt/LEDE Project, Buildroot, OpenEmbedded)
- Build scenarios (ebuilds, layers), software packaging (DEB/RPM)
Linux kernel
- Experience with BSP modifications and support (U-Boot hacking, BusyBox tweaking, DeviceTree re-configuration)
- Out-of-tree device drivers maintenance
- Basic experience with patch sets for real-time applications (RTAI, Xenomai)
Specific knowledge and skills
- Experience on all layers of the OSI model, including deep modification of physical and channel layers in existing solutions, as well as development of specific application-level protocols from scratch
- Development of custom modems and devices for peer-to-peer communications and mesh networks, including short- and mid-range radio (tenths of km)
- Design of instruments and aids for scientific experiments automation, R&D and industrial applications
- Experience in automatic regulation, PID control loops tuning, basic control theory
- Hard-realtime and soft-realtime systems development
- Capacitive sensors and active shielding (signal guarding)
- Generation and analysis of complex waveforms (e.g. for non-destructive examination, precise ultrasonic distance measurements)
- Optimization for ultra-low power consumption on all stages (design-level, part selection, software algorithms)
- Data acquisition and basic digital signal processing
- EMC/EMI management, noise and parasitic pickup analysis and filtering
- Circuit simulation and numerical modeling (FEM, FDTD methods)
- Basic experience with VNA: signal integrity analysis, impedance matching, antenna tuning
Software of choice
This is the list of my favorite engineering software and tools. This info might be useful during team building process (e.g. to increase interoperability). Multiple items within the same category are listed in order of proficiency decrease.
| General | |
|---|---|
| OS | Gentoo Linux |
| Desktop environment | KDE5 |
| Application framework | Qt (including Qt for Embedded and Qt Lite) |
| Electronics | |
| Schematic capture | gEDA/gschem |
| PCB layout | gEDA/pcb |
| Signal acquisition and analysis | sigrok |
| Circuit simulators | QUCS, ngspice (with spicelib), gnucap, XYCE |
| Microwave simulator | openEMS |
| AVR simulator | simavr |
| CAD | |
| 2D | LibreCAD |
| 3D | FreeCAD, OpenSCAD |
| Essential tools | |
| Compiler | GCC |
| Preferred shell | bash, zsh |
| Revision control | svn, git, cvs |
| Configuration and build systems | autotools, qbs, cmake, scons |
| CI framework | Buildbot |
| Multimedia processing | FFmpeg |
Portfolio
List of fully completed projects, in chronological order.
Remote operated manipulator for nuclear industry
During 2011-2012 I've designed a complex control system (electronics, firmware and software) for a remote operated manipulator for visual inspection of outer surface of VVER-1000 nuclear reactor pressure vessel. This was a large-scale project with enormous amount of R&D efforts across a diversity of scopes, covered by a strict safety requirements on all levels. In early 2013 manipulator has been commissioned and since then is in active operation at the customer site (Rivne Nuclear Power Plant, Varash, Rivne Oblast, Ukraine). Several inspections on different VVER-1000 units were performed during scheduled preventive maintenance so far without any issues.
Some of the project's major tasks are outlined below.
Hardware
- Main control electronics, based on distributed multi-master bus of MCUs
- Coordinate tracking for 6 axes, both stepper and servo-drives, combining data from absolute and incremental encoders
- Chassis speed control: independent PID loops with active synchronization for 4x BLDC motor-wheels (each with custom-designed electromagnetic brake coil)
- Remote operation via Ethernet, with higher-priority local handheld control unit
- Fault-tolerance on all levels by means of duplication and extensive error recovery algorithms and safe-modes
Remote operated manipulator
Chassis control electronics
Custom designed laser rangefinder, adapted for remote operation
Top-level diagrams for documentation
Board-level schematics and PCB layouts
Software
- Remote manipulator control tasks, visualization of all axes, data display
- Real-time data acquisition and processing from various sensors: encoders, ultrasound and laser rangefinders, limit switches, actuators
- Multi-channel video capture, synchronization, encoding and processing (e.g. telemetry overlay)
- Custom Gentoo-based GNU/Linux distribution (bootable LiveCD) with all project-related software, documentation, diagrams, tutorials, source files and tools (including toolchains for firmware generation)
Main control software
Axes state visualization widgets
Video-server application, synchronized with main control software
Motor-wheel's PID regulator tuning
Media publications
- Announcement (in Ukrainian, in Russian) on customer's website (Rivne Nuclear Power Plant)
- Article (in Ukrainian), "Energy" newspaper from 2014-07-31
Electrical discharge machine
In 2014 I was involved in designing and construction of CNC electrical discharge machine for precision metal processing in field of nondestructive examination for atomic energy. It is used to make precisely controlled (micron resolution) metal defects with various complex shapes. These are needed for testing, verification and calibration of nondestructive metal examination equipment and staff accreditation and certification.
Hardware
Electronics for EDM, developed from scratch:
- 3-axis CNC controller for step/dir signal generation and coordinate tracking
- Electrical discharge impulse generator (with massive R&D phases on noise resilience, impulse timings and different combinations of working fluid, electrode shapes and materials for burnout minimization)
- Various autonomous auxiliary operations available, including periodic lift-up (for working fluid pumping), Z-axis coordinate correction by limit switch, electrode burnout check using predefined reference point
- All available process parameters (reached depth, average arc current, processing speed, etc) transmitted to PC over the noise-resistant RS485 bus for further analysis
- All tasks are performed on MCU in hard-realtime mode
HV and power stages, resistor arrays, impulse generator
CNC setup
Workpiece ED processing with kerosene pumping
Software
- Control software with long term data logging capabilities
- All important data are plotted on the graphs and can be exported to raw binary or CSV format for further analysis
- Support for process-specific profiles for different kind of tasks
- Session-oriented data workflow (all graphs, logs and states are saved to/restored from special files)
- Incorrect software operation or other unexpected situations (e.g. communication link loss) has no effect on current running ED session due to fault tolerant measures in firmware architecture
EDM control software, profile manager
Data plots, loaded from session file
Anti-theft credit-card sized gadget
In 2015-2016 I've designed electronics for a pocket device to be used as an anti-theft/loss prevention gadget. More details about this project is available at the official website.
Hardware
Key features:
- Compact PCB (22x22mm)
- Capacitive proximity sensor with active one-side shielding (to prevent false alarms from body, when placed in a pocket)
- Advanced sensor data filtering techniques, intended to extend battery life and to reduce false alarms
- Bluetooth Low Energy up-link to host device (smartphone, tablet...)
- Ultra-low energy consumption (estimated lifetime of up to 6 months from a single CR2016 coin cell battery)
- Launched for limited mass-production
Schematics and layouts of BUZZARM (different revisions) and a mass-programmer
Inverted-F planar antenna simulation in openEMS
Various prototypes
Calibration of double-sided capacitive proximity sensor
PCBs, final version
Device is ready for mass-production
Post-project idea
Media publications
Other projects
Unstructured list of random projects
High-speed design of data converter module
Sample layout of FMC-board
