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🚁 Crazyflie 2.0 Nano-Quad Experiments 11-2025

The Crazyflie 2.0 nano-quadrotor is a compact but surprisingly capable flying laboratory. Despite its palm-sized form factor, it integrates IMU sensors, radio and BLE links, and a flexible firmware stack that invites modification. By tuning control gains, injecting disturbances, and logging sensor data in flight, it becomes an ideal platform for hands-on exploration of attitude control, state estimation, and fault response. Its modular expansion decks ranging from flow sensors and LPS positioning to additional processors extend the platform into indoor navigation and swarm coordination studies.

From an educational and research perspective, Crazyflie bridges simulation and full-scale flight testing. Algorithms for PID tuning, model predictive control, and sensor fusion can be rapidly iterated between MATLAB/Python simulations and real-world flights. Failures are low risk yet highly instructive, revealing the practical limits of controller robustness and communication latency. In this way, Crazyflie 2.0 serves as a safe, repeatable testbed where ideas in flight dynamics and autonomy can be validated before migration to larger unmanned aerial systems or spaceborne free-flyer concepts.

🎯 Misalignment in Optical Payloads 10-2025

Misalignment is one of the most persistent threats to the performance of precision optical systems, especially in spaceborne telescopes. Small tilts, decenters, or focus shifts between mirrors and lenses can convert a nominally diffraction-limited design into an aberration-dominated instrument. These errors distort the wavefront, broaden and skew the point spread function, and ultimately reduce the modulation transfer function, eroding effective ground resolution. In a satellite context, launch vibrations, thermal gradients, and structural creep continuously challenge the alignment budget defined on the ground.

Managing misalignment requires a full lifecycle approach. During design, tolerance analysis and Monte Carlo simulations map mechanical errors into image quality margins. In integration, metrology tools, interferometry, and star tests verify that the assembled system meets PSF and MTF requirements. On orbit, calibration sequences, focus sweeps, and analysis of stellar images reveal residual or evolving misalignments, allowing for software-based compensation where possible. This closed loop from analysis to testing to in-flight monitoring turns misalignment from an unexpected failure mode into a controlled parameter of high-performance optical payload engineering.

🌑 Lunar Dust: Effects on Satellites 9-2025

Lunar dust (regolith fines) is sharp-edged, glassy, and highly abrasive. Under UV and plasma it becomes electrostatically charged, adheres strongly to exposed surfaces, and can be lofted or transported by rocket plumes. For satellites and surface assets, this leads to five primary impacts: power loss from deposition on solar arrays; thermal drift as absorptivity/emissivity of radiators and coatings change; mechanical wear and jamming in hinges, latches, guides, and rails; communications risk from contaminated antenna apertures and mis-tuned radomes; and electrical hazards due to surface charging and contamination of connectors and insulators.

Mitigation blends design and operations. Use protective covers and baffles on critical hardware, dust-tolerant seals and connectors, abrasion-resistant or anti-adhesive coatings, and where practical electrodynamic dust shields (EDS). Plan plume-aware approach paths, designate dust-avoidance zones, and schedule periodic inspection/cleaning during missions. Qualification should include vacuum tests with lunar simulants (abrasion, thermal, contamination), demonstrating that system margins remain acceptable under dusty conditions.

🔭 MTF & PSF in Optical Systems 8-2025

The concepts of the Point Spread Function and the Modulation Transfer Function remain central to the evaluation of optical performance. The PSF characterizes the distribution of light from a single point source across the detector plane, providing a physical manifestation of the system’s resolution capability. The MTF, on the other hand, offers a frequency domain description that quantifies the system’s ability to preserve contrast across different levels of spatial detail. These two descriptions are not isolated, as the MTF is the Fourier transform of the PSF, and their combined interpretation enables a comprehensive understanding of imaging fidelity.

In practical terms, PSF and MTF are not abstract constructs but rather essential tools in the design and validation of Earth observation payloads. Misalignments, figure errors, and structural deformations alter the PSF, thereby degrading the system MTF and reducing the effective resolution. The performance of a remote sensing telescope is therefore judged not only by theoretical diffraction limits but also by the stability of these functions under operational conditions. Careful design, simulation, and calibration are required to ensure that the measured MTF remains within mission requirements throughout the satellite lifetime.

📡 RTL-SDR Experiments 7-2025

The introduction of low-cost software defined radios has created a unique environment for experimentation in communication and remote sensing. The RTL-SDR, although originally intended as a television tuner, has become a valuable platform for scientific exploration and engineering education. With a simple antenna and an open-source software stack, it is possible to observe aircraft transponders, receive weather satellite imagery, and monitor spectrum activity in real time. These experiments highlight the accessibility of signal processing and the importance of practical exposure to radio frequency systems.

Beyond hobbyist applications, the use of RTL-SDR in research contexts demonstrates the value of low-barrier tools for prototyping. Lessons in noise characterization, frequency stability, and antenna optimization provide insights that scale directly into the design of professional ground stations. The device’s limitations in sensitivity and dynamic range become teaching moments in understanding trade-offs that govern radio system performance. Through this lens, RTL-SDR serves not only as a tool for experimentation but also as a bridge between theory and practice in modern communication engineering.

🛰️ CubeSat Deployer Systems 6-2025

The development of standardized deployer systems has played a decisive role in the success of CubeSat missions. These mechanisms are responsible for maintaining the structural integrity of small satellites during launch and for ensuring their safe release into orbit. The simplicity of the Poly-Picosatellite Orbital Deployer established a template that has since been adapted to accommodate increasingly complex payloads and mission scenarios. By reducing integration complexity and guaranteeing compatibility with multiple launch vehicles, deployers have become a critical enabler of accessible space exploration.

Engineering challenges in deployer design extend well beyond the mechanical interface. The system must endure the severe acoustic and vibrational environment of launch while preventing inadvertent release. At the same time, it must guarantee a clean separation, minimizing tip-off rates and ensuring predictable satellite dynamics after deployment. Verification involves repeated testing under thermal vacuum and vibration conditions to replicate the operational environment. These considerations illustrate the importance of deployers not merely as containers but as sophisticated engineering systems whose reliability directly defines the success of CubeSat programs.