Feetech STS3035 12V 35kg.cm 360° Copper Gear TTL Serial Bus Servo

The Feetech STS3035 is a 12 V smart servo on a half-duplex TTL serial bus, built for robotic arms, humanoids, articulated mechanisms and other multi-servo rigs. A 12-bit magnetic encoder reports absolute position across the full turn, and the copper gear train carries 35 kg.cm at stall in a standard-servo footprint.

Key features

• Bus control with IDs 0–253 on one line at 38,400 bps to 1 Mbps

• 4096-step position resolution (0.088° per step), neutral at 2048, no mechanical end stop

• Rated torque 11.6 kg.cm at 900 mA; no-load speed 0.22 s/60° (about 45 RPM)

• Runs from 9–12 V, suited to higher-voltage robot power rails

• Ball bearings and a PA plus aluminium case around a 1:275 gearbox

Specifications

• Operating voltage: 9–12 V

• Stall torque: 35 kg.cm at 12 V

• Rated torque: 11.6 kg.cm (900 mA)

• Stall current: 2.7 A

• No-load speed: 0.22 s/60° (about 45 RPM)

• Idle current: 32 mA

• Gear ratio: 1:275

• Resolution: 0.088° (4096 steps per 360°)

• Control: half-duplex asynchronous TTL serial, digital packet

• Horn spline: 25T, 5.9 mm

• Dimensions: 40.2 × 20.2 × 40 mm

• Lead length: 15 cm

• Weight: 62.5 g

• Operating temperature: -10 to 60 °C

Bus servos need a TTL bus servo controller or adapter; they do not take a PWM signal from an RC receiver. Size the 12 V supply for 2.7 A per servo that can stall at the same time.