Servo position

FRONT
[LF] [RF]
[LB] [RB]
USB (Tail)

Servos Connection

FL Hip → D2
FL Knee → D3
FR Hip → D4
FR Knee → D5
BL Hip → D6
BL Knee → D7
BR Hip → D8
BR Knee → D9

MPU6050 Conenction

SDA → A4
SCL → A5
VCC → 5V
GND → GND

HC-05 Connection

TX → D0 (Nano RX)
RX → D1 (Nano TX via divider)
VCC → 5V
GND → GND

Initial Position before attaching servo horn

Servo Orientation

Upper Joint: Hip Pitch
90° = leg vertical
120° = forward
60° = backward
Lower Joint: Knee Pitch
90° = straight
120° = bent
60° = extended

Mechanical model

Leg DOF: 2 (hip pitch + knee pitch)
Foot style: round pad
Stance: Rectangular
Dimensions: 40mm + 55mm
Height/clear: ~95-100mm
Drive style: Tank turn + trot
Controller: Arduino Nano (USB tail)
Servos: SG90 x 8
IMU: MPU6050 (pitch-only correction)
Power: 2S → BEC 5V / power bank
Comms: HC05 + Serial fallback