📋 Engineering Design Reviewauto-generated for this build
Degrees of freedom—
Power draw (est.)est. typical load ~85 W avg · ~483 W peak
Battery (est.)est. 3S LiPo ~5800 mAh (~64 Wh) → ~45 min
Bigger packor build a 3S3P 18650 pack (~128 Wh, ~90 min) with spot-welder + nickel strip + smart BMS — all in the catalog
Energy systemLTO (lithium-titanate) · 3S1P · ~1.14 kg · 15000 cycles
Green optionSolar trickle/float: a ~13 W panel (pwr-solar-10w ×2) through an MPPT controller (pwr-mppt) makes it ~energy-neutral in daylight (assumes ~80% usable depth-of-discharge and ~5 peak-sun-hours — adjust for your location/battery).
RechargeCharge dock with spring contacts (manual park) or a swappable battery. Add pwr-charge-dock + pwr-charger-3s.
Brain / controllerFlight controller F4 (Betaflight)
Est. parts cost$99
Note: power, battery and cost figures are engineering estimates (estimated typical load), not measured values — verify on the bench.
Open design questions
▸ How long must it run between charges?
sets the battery capacity (Wh).
At ~85 W, 3S LiPo ~5800 mAh (~64 Wh) → ~45 min. Want more? scale Wh linearly.
▸ How will it recharge?
manual plug, dock, or wireless changes the chassis design.
Charge dock with spring contacts (manual park) or a swappable battery. Add pwr-charge-dock + pwr-charger-3s.
▸ Can the supply handle the current peaks?
peak draw ~483 W ≫ average — stalls/startup spike.
Use a pack with enough C-rate (LiPo handles it) + a buffer capacitor on the servo rail; fuse the battery.
▸ How are the boards mounted + wired (orderly + reproducible)?
serviceability + repeatability.
3D-printed trays on M2.5/M3 standoffs to each board's real footprint, one internal hole-grid standard, labeled JST connectors, battery low. The auto BOM + netlist make it 1:1 reproducible.
▸ Safety: e-stop, fusing, current limit?
protect the pack + people.
Inline fuse + a master switch / e-stop on the battery; BMS for over-current/over-discharge; soft-start the servo rail.
▸ Can the energy system be greener / smaller / longer-lived?
always optimise the energy part.
Solar trickle/float: a ~13 W panel (pwr-solar-10w ×2) through an MPPT controller (pwr-mppt) makes it ~energy-neutral in daylight (assumes ~80% usable depth-of-discharge and ~5 peak-sun-hours — adjust for your location/battery). Lighter pack: LTO (lithium-titanate) (~1.14 kg). Add a supercap to buffer peaks and shrink the pack.