Author Archives: Ryan

Sanyo pancake stepper motors with encoders

via Pololu Blog

We are now offering two new NEMA 17-size pancake bipolar stepper motors from Sanyo, each featuring an integrated high-resolution quadrature encoder and home channel for absolute positioning.

Stepper motor Steps per revolution Current rating (per coil) Voltage rating Resistance (per coil) Holding torque
#2279 42×31.5mm 200 1 A 5.4 V 5.4 Ω 1.9 kg-cm (26 oz-in)
#2278 42×24.5mm 200 1 A 3.5 V 3.5 Ω 800 g-cm (12 oz-in)

Side view of the SS2422-50XE100 42×31.5mm Sanyo pancake stepper motor.

Side view of the SS2421-50XE100 42×24.5mm Sanyo pancake stepper motor.

The integrated quadrature encoder operates from 5 V and has a resolution of 1000 P/R, which allows for 4000 counts per revolution (CPR) of the output shaft when counting both edges (i.e. rising and falling) of both channels (i.e. A and B). In addition to the A and B channel outputs, the encoder has a home channel, Z, that pulses once per revolution and can be used for absolute positioning. The encoder also has outputs for the inverse of A, B, and Z. A 15 cm (6″) encoder cable is included.

New 12V 1A wall power adapter

via Pololu Blog

We’ve replaced our original 12 V 1 A wall power adapter with a lighter, smaller version. This UL-listed 12 W, “wall wart”-style switching power adapter supplies up to 1 A at a regulated 12 VDC. The AC adapter works with input voltages of 100 to 240 VAC and has a 1.5 m (5 ft) DC power cord that is terminated by a center-positive, 5.5 × 2.1 mm barrel connector.

MechWarfare robot

via Pololu Blog

Forum member jwatte posted about a robot he made for the RoboGames MechWarfare 2017 competition. The goal is to build a walking robot that tries to hit an opponent’s pressure sensors with airsoft pellets or melee weapons. The robots walk around in a scaled-down cityscape field. Autonomous operation and teleoperation are allowed, but teleoperators must view the field from cameras mounted on the robot.

The mech uses a few Pololu voltage regulators: a 3.3 V, 1 A step-down regulator D24V10F3 powers a Xbee-Pro 900 XSC S3B wireless transciever and the laser pointer, a 6 V, 500 mA step-down voltage regulator D24V5F6 powers an OpenCM 9.04A robot logic board, and a adjustable step-down regulator D24V6ALV powers a 5.8 GHz wireless camera. A 250:1 Micro Metal Gearmotor LP 6V drives the plastic BB agitator that feeds the airsoft gun. The wiring harnesses used a lot of our pre-crimped wires.

For more details including a system block diagram see the forum post.

FEETECH Mini Servo FT1117M

via Pololu Blog

We added the FEETECH Mini Servo FT1117M to our expanding RC servo selection.This miniature-sized servo has a stall torque of 50 oz-in (3.5 kg-cm) and a speed of 0.11 sec/60° at 6 V. The pinion gear is plastic, but the rest of the gear train consists of all metal gears, allowing this servo to deliver the kind of speed and torque typically associated with larger servos.

Comparison to the Power HD 1711MG mini servo

This servo is a lower-cost alternative to the 1711MG from Power HD, which has nearly identical dimensions and performance. The two servos should be generally interchangeable for most applications. The picture below shows both the FT1117M and the 1711MG side by side:

Expect more new FEETECH servos in the coming weeks!

RoboClaw 2x60A Motor Controller (V6)

via Pololu Blog

The RoboClaw 2x60A motor controller (V5) we’ve been carrying has been replaced by the new RoboClaw 2x60A Motor Controller (V6). This powerful motor controller can drive two brushed DC motors with 60 A continuously at voltages from 6 V to 34 V, and it allows for peak currents up to 120 A. Version six adds a protective aluminum plate to the board bottom and ports for connecting optional cooling fans that are controlled based on the board temperature.

RoboClaw 2×60A Motor Controller (V6), bottom view.

The RoboClaw motor controllers from Ion Motion Control can control a pair of brushed DC motors using USB serial, TTL serial, RC, or analog inputs. Integrated dual quadrature decoders make it easy to create a closed-loop speed control system, or analog feedback can be used for position control.

For more information, see the product page.

Wall Power Adapter: 5.25VDC, 2.4A, 20AWG MicroUSB Cable

via Pololu Blog

We’ve added this Micro-USB wall adapter to our catalog. It can supply up to 2.4 A at 5.25 VDC (the USB specification’s maximum bus voltage), allowing for voltage drop due to power draw when powering 5 V electronics. It features a 1.5 m to 1.8 m (5 ft to 6 ft) DC power cord with 20 AWG wires that is terminated by a USB Micro-B connector, which makes it great for powering devices like a Raspberry Pi (especially newer Raspberry Pi models, like the Pi 3, which can draw a lot of current!).

Raspberry Pi connected to a Wall Power Adapter: 5.25VDC, 2.4A, 20AWG MicroUSB Cable.

For more details, see the product page.