Aerospace Engineer · Mechanical & Aerospace Engineering, UC San Diego
Sakshham R Sahai
I'm an aerospace engineer who designs, analyzes, and tests mechanical systems end to end: from first-principles load analysis and CAD to structures, vibration, and controls. I've built eVTOL concepts, flown a ducted-fan demonstrator, and validated models in wind tunnels and vibration labs. I enjoy work where the hardware has to survive contact with reality, in aerospace or mechanical design.
Upper-division lab sequence (MAE 175A) covering wind tunnel testing, vibration analysis, and multivariable control, plus a design capstone sequence (MAE 155).
Projects & Lab Reports
Each project links to its write-up. Reports open right here on the page.
Capstone design · MATLAB · OpenVSP/VSPAero · SolidWorks · Jan – Jun 2026
WHOVER: Winged Hovering Electric Rotorcraft
A single-seat hybrid fixed-wing/eVTOL personal air vehicle designed by a team of three to take off vertically from a driveway and fit in a one-car garage. I led the structural architecture.
Structures: aluminum inner frame (wing spars, ribs, seat subframe, landing struts) with a CFRP outer shell (fuselage, wing panels, rotor duct rings, canopy), following the Joby S4 and Archer Midnight precedents. Fiberglass or titanium interfaces keep aluminum and carbon from corroding each other.
Propulsion sizing: two tilting 1.7 m rotors sized with momentum theory across hover (110 kW), climb (125 kW), transition (90 kW), and cruise (56 kW). The mission closes on a 35 kWh battery with a 6.5 kWh reserve.
Why a hybrid: modeled in OpenVSP/VSPAero; deployed wings carry at least 40% of lift in cruise, so the rotors draw less power, and they also let the vehicle glide if power is lost.
Noise and packaging: owl-feather-inspired blades and tip winglets give a predicted 70.8 dB at 300 ft (under an 80 dB urban limit). Folding wings keep it inside a 20 × 12 × 8 ft envelope.
Also covered controls, emergency flight, and a risk matrix (concept at TRL 2).
MTOW 460 kg35 kWh battery≥40% wing lift70.8 dB SPL
Test stand · IMU · Raspberry Pi Pico · MAE 155B
Ducted Coaxial PAV: Propulsion & Attitude Control
A hand-built ducted coaxial demonstrator I tested and flew to see how a vehicle behaves versus its model.
Measured thrust, torque, and power vs. RPM for 7" props on 2300 KV motors: about 4.3 N near 10,000 RPM at over 60 W, matching manufacturer specs.
Found moments of inertia with swing and bifilar pendulums (Ixx, Iyy, Izz = 0.0057, 0.0055, 0.0102 kg·m²) and compared to Fusion 360 CAD.
Built a closed-loop attitude controller with an IMU, a Pico, and servo-driven vanes in the duct exit.
Lifted several inches at about 95% of available power. The as-built mass overran the estimate because of wiring, adhesive, and mounts, which ate the thrust margin.
MATLAB · Python · Mar – Jun 2025
Aircraft Wing & Spar Structural Analysis Tool
A MATLAB tool that sizes and checks wing and spar structures from the cross-section up.
Computes cross-section stiffness (EA, EIyy, EIzz, EIyz, GJ) for single-cell sections using thin-wall beam theory, with user-defined aluminum or CFRP properties.
Simulates five critical V-n load cases and reports spanwise shear, bending moment, stress, twist, and deflection.
Material trade: switching aluminum to CFRP cut spar mass 80.7% (62.7 to 12.1 lb) and wing mass 88.2%.
−80.7% spar mass−88.2% wing mass
LabVIEW · MATLAB · MAE 175A · Jan – Mar 2026
Wind Tunnel Testing: Clark Y-14 Airfoil
A three-week campaign to measure lift, drag, and pitching moment, and to check the methods against each other.
Calibrated fan power to airspeed with a Pitot-static probe (velocity uncertainty under 0.004%).
Ran Re = 2–5 × 10⁵ and AoA from −4° to 20° using pressure taps, a wake-survey rake, and a strain-gage sting balance.
CL, CD, and CM agreed across three independent methods within 2σ; stall shifted from 6° to 12° as speed rose from 20 to 50 m/s.
MATLAB · Accelerometers · Digilent AD2 · MAE 175A
Structural Vibration & Modal Analysis
Found how structures vibrate, first on a 3-story shear building and then on a helicopter rotor blade.
Found three building modes (10, 17.3, 28 Hz) with swept-sine tests, FFT, PSD, and the Hilbert transform.
Derived transfer functions H21(s) and H31(s) and estimated damping (0.073) with the half-power method, checked against Bode plots.
On the blade, found first out-of-plane bending near 0.056 Hz with the 179° root-to-tip phase flip expected for that mode.
MATLAB · Simulink · Quanser · MAE 175A
Multivariable Control: 2-DOF Helicopter
Modeled and controlled a pitch/yaw platform whose two axes interfere with each other.
Identified a first-order MIMO model from open-loop step tests and quantified the cross-axis coupling.
Designed PID loops by sequential loop closing, checked with Nyquist and Bode margins, then moved to a 6-state LQR with integral action and a decoupling pre-compensator.
Tracked pitch (±5°) and yaw (±20°) references; residual oscillation traced to unmodeled effects such as a loose stand, slip-ring friction, and wall downwash.