TranslateChallenges
New challenges every Monday and Friday. Use everyday materials, get creative, and earn +10 points for each attempt you share.
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Exoplanetary Transit Photometry Reconstruction
Design a high-precision experimental apparatus to simulate a multi-planet transit system using a single modulated light source and varied occluding masks. You must develop a signal processing protocol to extract individual planetary radii and orbital periods from the noisy aggregate light curve data, accounting for limb-darkening effects and sampling jitter. Ensure the final model can distinguish between transit depth variations and system noise at a confidence level of 3-sigma.
Materials: LED light source, PWM controller, opaque cardstock, circular aperture cutters, photodiode sensor, Arduino or equivalent microcontroller, and a data-logging interface.
Seismic Liquefaction Mitigation and Foundation Stability
Design and construct a scaled foundation system capable of supporting a weighted superstructure atop a saturated granular soil medium during simulated seismic liquefaction events. Participants must devise a mitigation strategy, such as dynamic compaction, soil reinforcement, or drainage systems, to maintain vertical displacement within a 5mm tolerance when subjected to horizontal harmonic excitation. Your final report must include an analysis of pore-water pressure dissipation rates and effective stress distribution across the failure plane.
Materials: Fine-grained sand, plastic container, water, small vibrating motor or eccentric weight mechanism, lead weights, porous mesh fabric, and rulers.
Diffusion-Limited Phase Separation Optimization
Design and execute an experiment to measure the mass transfer kinetics of a ternary liquid-liquid extraction system using immiscible household liquids. You must calculate the partition coefficient and determine the influence of interfacial surface tension modifiers on the rate of phase separation. Your final report should model the system's approach to equilibrium using a modified Fickian diffusion equation.
Materials: Vegetable oil, distilled water, isopropyl alcohol, food-grade surfactant, graduated cylinders, precision scale, timer.
Adaptive Impedance Locomotion Challenge
Design and construct a quadrupedal robotic mechanism capable of traversing a terrain of unpredictable stiffness, such as varying layers of foam and loose sand. Your system must demonstrate dynamic gait adjustment by implementing closed-loop impedance control to maintain a stable center of mass without utilizing pre-programmed pathing. The final evaluation will measure the deviation of the center of gravity during transition across shifting mechanical impedance zones.
Materials: Microcontroller (Arduino or ESP32), four micro-servos, elastic silicone bands, cardboard or laser-cut acrylic, various densities of packing foam, and loose play sand.
Seismic Resilience of Modular Lattice Towers
Design a self-supporting vertical structure at least 40cm tall that utilizes a braced-frame geometry to resist lateral shear loads. Your structure must support a 500g eccentric mass at the apex while enduring a 30-second simulated harmonic oscillation test at varying base frequencies. You must prioritize material efficiency and calculate your displacement-to-height ratio before and after the vibration test.
Materials: Wooden coffee stirrers, hot glue, masking tape, fishing line, cardboard, and a smartphone with a vibration sensor app.
Precision Tolerance Fit Challenge
Design and manufacture a mechanical press-fit assembly using two distinct materials that maintains an interference fit capable of resisting 5kg of axial load without adhesives or external fasteners. You must document the theoretical interference calculation and demonstrate the assembly's failure point under a calibrated stress test. The final deliverable must evaluate how material elasticity and thermal expansion coefficients influenced your assembly tolerances.
Materials: Calipers, assorted rigid plastics, metallic scraps, sandpaper, and a household scale.
Exoplanetary Transit Photometry Reconstruction
Design and calibrate a high-sensitivity light-intensity sensor array capable of capturing sub-millimagnitude fluctuations in a simulated stellar source. You must develop a signal processing algorithm to extract periodic dip data from the noise floor, accurately calculating the radius ratio of the transiting body relative to the host star. The final submission requires both the sensor calibration log and the successful estimation of the transit depth within a 2% error margin.
Materials: Microcontroller with analog-to-digital converter, high-precision phototransistor, LED light source, opaque shutter material, neutral density filters, and a rigid dark-chamber housing.
Bio-Inspired Hydrodynamic Dampening Array
Design and prototype a modular, passive-actuated flow control device capable of mitigating vortex-induced vibration (VIV) on a cylindrical pylon submerged in high-velocity current. The mechanism must utilize flexible, biomimetic materials to adjust its surface topology in response to Reynolds number variations, thereby minimizing drag coefficient without external energy input. Validate the efficiency of your dampener by measuring the suppression of transverse oscillations in a scaled water-channel simulation.
Materials: Flexible silicone sheeting, thin high-density polyethylene strips, waterproof structural adhesive, weighted fishing line, a deep plastic storage bin, and a variable-speed submersible aquarium pump.
Eddy-Current Levitation Stabilization
Design and construct an active electromagnetic suspension system capable of maintaining a stable equilibrium for a conductive disk using only passive eddy-current damping and a feedback-controlled solenoid. You must characterize the magnetic field gradient and tune your PID controller parameters to minimize low-frequency oscillation within a 20mm air gap. The final validation requires demonstrating sustained levitation while applying a controlled mechanical perturbation to the disk.
Materials: Copper-enameled wire, iron core rod, Arduino microcontroller, Hall effect sensor, MOSFET power switch, neodymium magnets, and a thin aluminum disk.
Microfluidic Hemostatic Scaffold Design
Design and fabricate a bio-inspired microfluidic channel system capable of simulating controlled platelet aggregation under laminar shear stress conditions. You must analyze the impact of channel geometry on clot formation kinetics and demonstrate a method to quantify thrombus occlusion times using your apparatus. Your solution should focus on optimizing perfusion rates and structural surface modifications to enhance hemocompatibility.
Materials: clear acrylic sheets, food-grade silicone sealant, syringe pump, flexible plastic tubing, red food coloring, cornstarch suspension
Exoplanetary Transit Spectroscopic Modeling
Design and construct a physical analog model to simulate the light curve degradation of a star during planetary transit, accounting for limb darkening effects and potential starspot interference. You must calibrate your model to distinguish between planetary transit and intrinsic stellar variability signatures using a light-sensitive diode and a varying opacity mask. Finally, provide a mathematical derivation that correlates your experimental signal-to-noise ratio with the projected exoplanetary radius.
Materials: High-intensity LED, Arduino or microcontroller, light-dependent resistor (LDR), neutral density filters, rotating cardstock with varying aperture shapes, and black opaque spray-painted glass.
Bio-Inspired Variable Geometry Hydrofoil
Design and construct a scale-model hydrofoil assembly capable of transitioning between high-lift takeoff configuration and low-drag high-speed cruise configuration. You must demonstrate active or passive pitch control using fluid dynamics principles to maintain stability under varying flow velocities. The system will be evaluated on lift-to-drag ratio efficiency and the ability to maintain a consistent depth in a simulated wave tank environment.
Materials: Thin PET plastic sheets, aluminum wire, waterproof marine epoxy, lead weights for ballast, rubber bands, and a programmable micro-servo.
Subsurface Liquefaction Mitigation Analysis
Design a small-scale soil foundation system that maintains structural integrity under rapid dynamic loading to simulate seismic-induced liquefaction. Participants must engineer a drainage or compaction strategy using granular media that prevents total pore pressure buildup and subsequent bearing capacity failure when subjected to controlled harmonic vibrations. Document the volumetric strain and settlement ratios observed before and after the simulated seismic event.
Materials: Fine-grain sand, saturated silt mix, vibrating platform or mass-balanced shaker, transparent acrylic column, water, and a lightweight structural model.
Stochastic Thermal Regulation Challenge
Design and implement a PID control loop capable of maintaining a constant temperature in a container subject to unpredictable, high-frequency external thermal noise. You must characterize your system's dead time and noise floor, then tune your controller to minimize steady-state error while maintaining stability during introduced step-load disturbances. Document your loop response curves and justify your tuning parameters based on the system's identified transfer function.
Materials: Microcontroller with PWM output, NTC thermistor, MOSFET, heat sink with resistive heating element, USB-to-serial interface for data logging, breadboard and jumper wires.
Bio-Inspired Hydrodynamic Boundary Layer Control
Design a scale-model hull geometry that utilizes active or passive surface texturing to induce turbulent transition delay and minimize skin friction drag. Evaluate the efficacy of your design by measuring the flow velocity differential across a closed-loop recirculating tank versus a baseline flat-plate control model. Provide a technical brief analyzing the Reynolds number regimes where your texture geometry achieved peak drag reduction.
Materials: Polyvinyl chloride sheets, waterproof adhesive, 3D printing filament, non-toxic micro-beads for flow visualization, variable speed pump.
Microfluidic Hemostatic Scaffold Optimization
Design and prototype a microfluidic device capable of simulating interstitial flow to analyze the degradation rate of a synthetic hydrogel scaffold intended for rapid hemostasis. You must quantify the structural integrity of your material against shear stress levels ranging from 0.5 to 2.0 dyne/cm² while demonstrating precise control over localized fluid permeability. Document the trade-offs between scaffold cross-linking density, pore interconnectivity, and the resulting mass transport kinetics observed during your simulated vascular trauma trial.
Materials: Syringes, silicone tubing, gelatin or agar powder, food coloring, flexible plastic sheets, adhesive sealant, and a smartphone camera for time-lapse analysis.
Dynamic Ballast Oscillation Stabilization
Design and construct a scale model of a semi-submersible vessel capable of maintaining a stable horizontal platform while subjected to multi-axial wave simulation. You must integrate a passive pendulum or active fluid-transfer ballast system to dampen harmonic resonance induced by rhythmic input at the vessel's natural frequency. Success is measured by minimizing the pitch and roll excursion amplitudes relative to a control hull without damping mechanisms.
Materials: Plastic foam blocks, small plastic containers, PVC piping, metal washers or heavy hex nuts, rubber bands, clear acrylic water basin, and a stopwatch.
Kinematic Constraint Analysis: The Passive Gripper Challenge
Design and construct a purely mechanical, passive-actuation end effector capable of grasping three distinct objects of varying geometry and mass using only gravity or a single linear displacement input. Your solution must demonstrate a clear grasp of underactuated linkage synthesis and force closure principles while maintaining a structural mass under 500 grams. Evaluated based on cycle reliability, grip stability under a 2G acceleration load, and the integration of a compliant transmission mechanism.
Materials: 3D printer filament, stiff steel wire, elastic rubber bands, cardboard scraps, hot glue, assorted fasteners, and a counterweight.
Microfluidic Hemodynamic Analog Design
Design and fabricate a multi-channel microfluidic device capable of simulating pulsatile flow through a bifurcated arterial model with a localized stenosis. Participants must demonstrate precise control over fluid shear stress gradients and incorporate a passive filtration mechanism to trap 10-micron surrogate particulate matter. The final design must provide quantitative data on flow rate consistency and pressure drop across the constriction under varied input frequencies.
Materials: Transparent silicone sealant, flexible tubing, clear acrylic sheets, high-viscosity food-grade glycerin, red food coloring, syringe pump mechanism, precision syringe needles.
Subterranean Aquifer Remediation Simulation
Design a scale-model filtration system capable of sequestering simulated heavy metal contaminants from a saturated porous medium while maintaining controlled hydraulic conductivity. You must calculate the breakthrough curve of your filter media to determine the adsorption capacity and residence time required for effective decontamination. Your solution must demonstrate the ability to process a continuous influent stream without exceeding a specified pressure differential.
Materials: Sand, activated carbon, aquarium tubing, plastic storage bins, food coloring, a stopwatch, and a graduated cylinder.
Low-Latency Precision Pulse Discriminator
Design and implement a high-speed signal discrimination circuit capable of distinguishing between sub-microsecond pulse widths with varying amplitudes. You must minimize jitter and propagation delay while maintaining an output signal integrity sufficient for TTL compatibility. Focus on minimizing parasitic capacitance and optimizing the comparator thresholding logic to handle high-frequency noise rejection.
Materials: Breadboard, high-speed op-amp or comparator ICs (e.g., LM393 or TLV3501), resistors, capacitors, multimeter, and a function generator.
Asynchronous Memory Interconnect Arbiter
Design and implement a robust hardware arbiter for a multi-master bus system that resolves requests using a fair round-robin scheduling algorithm with priority-based preemption. You must simulate the logic using a hardware description language and verify timing closure under non-deterministic latency constraints common in asynchronous clock domain crossings. The final solution must demonstrate minimized jitter and zero-deadlock state transitions under high-load synthetic traffic patterns.
Materials: FPGA development board, logic analyzer, breadboard, signal generator, and a workstation with Verilog or VHDL simulation tools.
Autonomous Atmospheric Density Profiling Mission
Design and construct a high-aspect-ratio passive aerostat capable of maintaining a stable, altitude-controlled glide path while deploying a serialized data collection payload. You must model and demonstrate a mechanism for atmospheric buoyancy compensation that accounts for thermocline-induced lift fluctuations without active propulsion. The success metric is defined by the stability of the descent rate and the accuracy of the spatial mapping of simulated thermal currents.
Materials: Mylar sheets, lightweight balsa wood dowels, adhesive tape, high-tensile fishing line, small calibrated lead weights, and a digital barometer or inclinometer.
Tension-Compression Hybrid Truss Optimization
Design a truss system that maintains structural integrity while spanning a 40cm gap and supporting a 5kg dead load at the center point. You must minimize total material mass while maximizing the stiffness-to-weight ratio to prevent deflection exceeding 5mm. Document the calculated failure points for each joint under maximum stress to evaluate the load distribution efficiency.
Materials: Thin balsa wood strips, cyanoacrylate adhesive, wax paper, ruler, precision hobby knife, digital scale.
Continuous-Flow Microfluidic Extraction Optimization
Design and construct a multi-stage microfluidic extraction manifold that achieves a >90% partition coefficient for a surrogate solute between immiscible aqueous and organic phases. You must demonstrate steady-state performance while characterizing the mass transfer resistance across the liquid-liquid interface under varying laminar flow velocities. Please provide a rigorous analysis of your residence time distribution (RTD) and its impact on your overall extraction efficiency.
Materials: Clear rigid plastic tubing, food-grade silicone sealant, syringes, isopropyl alcohol, food coloring, mineral oil, and a digital scale.
Bio-Inspired Variable Geometry Hull Optimization
Design and construct a scale model of a hull section utilizing flexible, non-rigid materials to simulate active morphing for drag reduction at varying Froude numbers. Your prototype must demonstrate a mechanical or tension-based actuation system capable of altering the hull's wetted surface area or bow profile to transition between displacement and semi-planing modes. Documentation must include an analysis of the center of buoyancy shift relative to the morphing geometry.
Materials: Flexible TPU sheets, thin steel tension cables, small servo motors, waterproof adhesive, polystyrene foam, and basic hand tools.
Liquefaction Mitigation Design Challenge
Design and construct a soil foundation model capable of supporting a weighted structural load while subjected to simulated seismic liquefaction. Participants must engineer a drainage or densification system within saturated granular media to prevent catastrophic bearing capacity failure during a sustained 60-second vibration test. Success is measured by minimizing total vertical settlement and relative tilt of the structural footing upon completion of the test cycle.
Materials: Clear plastic container, fine-grain sand, water, small flat rigid plate, heavy metal washers or bolts, handheld vibrating massage tool or mechanical shaker.
Precision Power Harvesting via Impedance Matching
Design and implement a high-efficiency power harvesting circuit capable of rectifying and conditioning low-amplitude RF signals from a controlled 2.4GHz source. You must achieve maximum power transfer by dynamically tuning the input impedance to match the antenna source impedance across a varying load, while maintaining a DC output stability within 5% ripple under shifting environmental interference. Document your efficiency curves and the methodology used for your impedance matching network architecture.
Materials: Copper wire for antenna construction, high-frequency Schottky diodes, variable capacitors or varactor diodes, breadboard, multimeter, and an RF signal generator.
Thermoelectric Waste-Heat Harvesting Array
Design and construct a prototype thermoelectric generator array capable of converting low-grade thermal waste from a standard household appliance into a measurable voltage. You must optimize the heat sink geometry and thermal interface materials to maximize power density while maintaining a stable temperature gradient. The final assembly must demonstrate sustained power output under a steady-state thermal load.
Materials: Peltier modules, aluminum heat sinks, thermal paste, multimeter, adjustable laboratory power supply, IR thermometer, and household heat source like a toaster or radiator.
Thermal Energy Harvesting and Micro-Grid Storage Optimization
Design a small-scale prototype that converts a low-grade waste heat source into a stable electrical output for charging a supercapacitor. You must optimize the conversion efficiency using a Peltier module and implement a DC-DC boost converter circuit to regulate voltage output despite fluctuating temperature gradients. Success is measured by maximizing the total joules stored over a continuous one-hour cycle.
Materials: Peltier module, supercapacitor, multimeter, breadboard, resistors, LEDs, copper heat sinks, DC-DC boost converter module, thermal paste.
Dynamic Seismic Mitigation for Tall-Structure Prototypes
Design and construct a vertical structure at least 60cm in height that must withstand a 30-second sustained horizontal oscillation test at a frequency of 2Hz. You must incorporate an integrated, non-powered tuned mass damper (TMD) system to minimize structural deflection at the apex during excitation. Success is measured by the ratio of structural stiffness to the mass of the damping system while maintaining integrity under base-load displacement.
Materials: Corrugated cardboard, hot glue, wooden skewers, fishing weights or metal nuts for mass, thread or thin rubber bands, and a stopwatch.
Bio-Inspired Variable Geometry Hull Optimization
Design and construct a scale model of a submersible vessel featuring a bio-inspired, morphing hull mechanism that transitions between low-drag laminar flow for transit and high-drag resistive stabilization for precision hovering. Evaluate the structural integrity of the articulated joints under simulated hydrostatic pressure while maintaining a neutral buoyancy profile using a dynamic ballast system. Demonstrate the mechanical reliability of the geometry shift by documenting the transition speed and energy consumption relative to hydrodynamic output.
Materials: High-density foam, flexible silicone sheeting, micro-servos, waterproof epoxy, varied weights for buoyancy, stiff plastic linkages, and adhesive sealants.
Hygroscopic Actuator Optimization
Design a passive, multi-stage hygroscopic actuator capable of generating a predictable linear displacement of at least 5mm when transitioning between 30% and 80% relative humidity. You must characterize the material fatigue limit across 50 cycles and provide a mathematical model representing the force-displacement curve of your composite structure. Success is measured by the repeatability of the stroke length and the minimization of hysteresis during the dehumidification phase.
Materials: Cellulose-based papers, varying thicknesses of adhesive tape, hydrophobic wax coatings, and precision digital calipers.
Vascular Bypass Flow Simulator
Design a model of a human arterial system that demonstrates how to bypass a restricted blood vessel using a synthetic graft. You must create a functional fluid circuit that maintains steady flow despite a simulated arterial blockage while preventing leaks at the connection points. Your device will be evaluated based on the pressure consistency and the structural integrity of your bypass connection.
Materials: Flexible plastic tubing, food coloring dyed water, small hand pump or large syringe, tape, waterproof sealant or clay, and cardboard support structure.
The Resilient Hull Challenge
Design and construct a scale model ship hull that can successfully transport a payload of 200 grams across a basin of water without capsizing. Your design must feature a watertight cargo bay and demonstrate structural stability when subjected to lateral waves created by a standardized stirring motion. Success is measured by the vessel's ability to maintain a level deck and remain buoyant for at least three consecutive minutes.
Materials: Aluminum foil, cardboard, duct tape, plastic wrap, modeling clay, and a plastic storage bin for testing.
The Autonomous Sorting Sorter
Design and build a mechatronic system capable of automatically sorting a mixed pile of three different types of small household items into separate containers based on physical properties like size or weight. Your device must utilize a motorized conveyor or mechanical arm mechanism controlled by simple logic to ensure at least 80% sorting accuracy. The challenge focuses on the integration of mechanical movement with basic sensor-based decision making.
Materials: Cardboard, rubber bands, popsicle sticks, DC motors, AA batteries, AA battery holder, push-button switches, and small containers.
The Automated Sun-Tracker
Design a passive or active control system that keeps a light sensor oriented directly toward a moving light source. Your mechanism must demonstrate automatic correction when the source shifts position and maintain a stable alignment for at least 30 seconds. Participants should focus on minimizing oscillations during the tracking process.
Materials: Small servo motor, photoresistors, breadboard, jumper wires, Arduino or microcontroller, cardboard, and rubber bands.
The Automated Budget Tracker
Design a Python script that parses a raw CSV file of bank transactions to categorize spending by type. The system must generate a summary report displaying the total expenditure per category and flag any single transaction that exceeds a user-defined threshold. Ensure your code includes basic error handling for empty files or invalid data formats.
Materials: Laptop or desktop computer, Python interpreter, IDE of choice, sample CSV dataset
The Urban Stormwater Filtration Challenge
Design a small-scale gravity-fed filtration system to purify simulated urban runoff contaminated with sediment and oil. Your prototype must effectively reduce turbidity and trap visible pollutants while maintaining a steady flow rate over a five-minute testing period. Focus on layering media to maximize water quality through physical and chemical absorption.
Materials: Plastic bottles, sand, gravel, activated charcoal, coffee filters, cotton balls, and a container of murky water mixed with a teaspoon of vegetable oil.
The Liquefaction Challenge
Design and build a foundation model that can support a heavy weight while subjected to simulated seismic vibration on a saturated soil bed. Participants must observe how water saturation levels affect the stability of their structure and refine their design to prevent settlement or tipping. The goal is to create the most stable foundation using varying soil compositions and structural support techniques.
Materials: Sand, plastic bin, water, small rocks, cardboard, popsicle sticks, glue, and a heavy object for loading.
Thermal Barrier Bridge Challenge
Construct a bridge span that measures at least 20cm in length using only your available materials. The bridge must support a weighted object at its center while minimizing heat transfer from a heated pad placed on one end to a sensitive item on the other. You must balance structural load-bearing capacity with effective thermal insulation properties.
Materials: Cardboard, aluminum foil, cotton balls, masking tape, wooden skewers, and a thermal indicator like a chocolate chip or an ice cube.
Build a cardboard robot gripper that opens and closes
Build a simple robotic gripper from cardboard that can pick up a small object (a coin, a marker). Use string, rubber bands, or syringes as 'actuators' you control by hand. The goal is to understand how a robot turns a small input motion into a useful grip. Document how your mechanism works.
Materials: Cardboard, string or rubber bands, a couple of syringes (optional), tape
Design a paper airplane that stays aloft for 3 seconds
Using a single sheet of paper, design and fold a paper airplane that glides for at least 3 seconds when thrown gently. Experiment with wing shape, nose weight (a small paperclip), and winglets. Submit a photo and tell us what design choices made the biggest difference.
Materials: A sheet of paper, a paperclip (optional), a stopwatch (your phone)
Build a water filter from household items
Using a plastic bottle cut in half and layers of cotton, sand, and gravel, build a simple water filter. Run muddy water through it and see how clear it gets. Document your layers and your results with a photo. (Don't drink the filtered water — this is an experiment, not a purifier!)
Materials: Plastic bottle, cotton balls, sand, gravel, muddy water
Sketch a machine in your home
Find any machine or mechanism in your home (a can opener, a door lock, scissors, a lamp switch, a stapler). Sketch how you think it works on the inside — label the parts and the forces. You don't need to be right; you need to think like an engineer. Submit a photo of your sketch and a short explanation.
Materials: Paper and a pencil
Build a paper bridge that holds 10 coins
Using only 1 sheet of paper and a little tape, build a bridge that spans a 20cm gap between two books and holds at least 10 coins in the middle. No glue, no extra materials. How strong can you make it? Hint: think about folding the paper into shapes.
Materials: 1 sheet of paper, a small piece of tape, 10 coins, 2 books
