📐 Circuit SchematicClick pin → click pin to wire Right-click to cancel · Drag to rearrange
Add parts from library to see them here
Parts Library
Arduino Uno
Microcontroller brain
L298N Driver
Dual H-Bridge
LiPo Battery
7.4V 2200mAh
HC-SR04
Ultrasonic sensor
DC Motor (L)
Left drive wheel
DC Motor (R)
Right drive wheel
4-Wheel Chassis
Robot base frame
IR Sensor (L)
Left line detector
IR Sensor (R)
Right line detector
Torso Chassis
Add this first
Sensor Head
Cameras + status ring
Leg Assembly
Links, ankles and feet
Arm Assembly
Links and grippers
Hip Servos
×2 — carry the most torque
Knee Servos
×2
Ankle Servos
×2 — these hold it upright
Arm Servos
×4 — shoulder and elbow
Controller
ESP32 + servo bus
IMU
Tells it which way is down
Battery Pack
3S — 20 servos at once
Rocket Airframe
Add this first
Stage 2 Engine
Liquid — restartable, throttleable
Drogue Parachute
Small — out at apogee
Main Parachute
Big — out low down
Arming Switch
No pyro fires without it
GPS Module
Optional — where it went
TVC Gimbal Mount
Optional — lets it steer
Nose Cone
Shapes the air, carries the CP
Fin Set
Without these it tumbles
Stage 1 Motor
Booster — lifts it off the pad
Stage 2 Motor
Sustainer — lights after staging
Payload Probe
Every gram costs fuel
Flight Computer
ESP32 + 2 pyro channels
Altimeter
BMP280 — finds apogee
Igniters
Two channels, one per stage
Separation Servo
Stages + parachute
Flight Battery
2S — pyros need current
Arm Base Plate
Add this first
Base Servo
MG996R — turns the arm
Shoulder Servo
MG996R — lifts the arm
Elbow Servo
MG996R — bends forearm
Drone Frame
ESP32 + IMU — add this first
Motor M1
Front-left, CW
Motor M2
Rear-left, CCW
Motor M3
Rear-right, CW
Motor M4
Front-right, CCW
Propellers
45mm — 2 CW + 2 CCW
LiPo 1S
3.7V 250mAh, 7g
MPU6050 IMU
Which way is down
BMP280 Barometer
How high it is
VL53L0X Range
Distance to the floor
Flow Deck v2
Optical flow + ToF
Gripper
SG90 + parallel jaws
Pilotautonomous
Arrow keys fly it · W/S height · T take off · L land
How to use1. Add Chassis first 2. Click any card → snaps to chassis 3. Drag chassis → all parts move
4. Click glowing pin → wire mode
5. Click 2nd pin → connect! Position a part
Double-click part → selects it
Right-click selected → position box
ESC (×2) or click empty → deselect
The SpyralDrone library
There is no set list of missions. Write whatever you want the drone to do — these are
the calls you have, and the rules they follow.
Connections Needed
Wrong Connections
Status
Add parts from the library.
✦ AI Trainer▾
Hi! I'm your AI Robotics Trainer. I can see your circuit and code. Ask me anything — "why isn't my robot turning?", "what's wrong with my wiring?", or "explain motor drivers".
Type on the left, watch the right. Burn time, total impulse, motor class,
dry mass and Δv are never typed in — they are what your choices come to.
The mission
Every gram of payload is carried by propellant, which is carried by
structure, which is carried by more propellant. This is where a rocket's size comes from.
kg
kg
Stage 1 — the booster
Its job is to get off the pad, so thrust matters more than efficiency here.
kg
N
s
Stage 2 — the sustainer
It burns in thin air where efficiency is everything. A liquid engine can
shut down and restart, which is the only way to do a transfer burn and a capture burn.
kg
N
s
Airframe and the air
A wider body holds more propellant, and pays for it with frontal area —
drag goes with the square of the diameter.
mm
°
Fins and nose — will it fly straight
A rocket turns about its centre of gravity. If the centre of pressure
sits behind it, every wobble corrects itself; ahead of it, every wobble grows. The gap
between them, in body diameters, is the static margin — build to 1–2.
mm
mm
mm
mm
mm
Send it somewhere — the mission
This works backwards: pick the destination, and it tells you what
vehicle could do it. Set Isp and ε above to the figures a real launch vehicle achieves
(443 s and 0.09 for a cryogenic stage) and the impossible becomes ordinary.
km
°N
Recovery
Canopy area sets how fast it hits the ground. Under about 6 m/s the
airframe survives; over 12 it is scrap.
m²
m²
m
What this comes to
All of it derived. Change anything on the left and watch which of
these move together.
⚠️ Fix These Before Running
⚙️ Pre-flight Calibration
A drone will not fly straight out of the box. These four checks are the
ones that catch a real build — three of them read what you actually wired
and fitted, so fix the hardware and run them again.
⚡ Flash to Real Arduino
Your sim code → compiled → flashed to your board via USB browser connection.
⚠️ WebSerial requires Chrome / Edge 89+ on desktop. Firefox is not supported.
1Compile Code on Server
Ready to compile…
2Connect board via USB
Plug the board into your computer's USB port, then click Connect.
3Flash Firmware
Waiting…
🛒 Bill of Materials
Component
Qty
Price (INR)
Buy
Prices approximate. Check robu.in / Amazon India for latest.
TOP
ISOMETRIC
FRONT
SIDE
Part
🗺️ Scene Editor
ISO: left-drag orbit · right-drag pan · scroll zoom | TOP/FRONT/SIDE: right/middle-drag pan · scroll zoom · R reset view · H reset all · Dbl-click maximize
🔌 Wiring mode — click another pin to connect · ESC to cancel