Posts by Ryan
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Are you attending CES or in Las Vegas on Wednesday, January 10th? You can join Pololu and LVBots any time from 5 p.m. to 8 p.m. for CES Open House 2018! Like last year, LVBots members will be showcasing their robotics and electronics creations, Pololu will be giving tours of our manufacturing and other operations, and you can present your company or your projects. We will provide food. Registration and other details are on the LVBots Meetup page.
The Boe-Bot Robot Kit is an educational kit complete with parts and a textbook for building and programming your own robot. No previous robotics, electronics, or programming experience is required; the kit does not require soldering.
Pololu customer Yvon Hache made this 3D-printed aerial photography rig that he shared in a forum post. The rig, trailing 100 feet below the kite, automatically triggers a camera to take pictures at three tilt angles and sixteen pan angles. It incorporates an ARM Cortex-M4 microcontroller from Texas Instruments (32-bit, 80 MHz, TM4C123GH6PZ), an AltIMU-10 v5, Pololu voltage regulators, and a Zigbee module for wireless remote control. Yvon uses a pair of Pololu micro metal gearmotor extended brackets per motor—one mounts the motor to the frame and the other protects the encoder assembly.
More kite rig information and pictures can be found on Yvon’s website.
We were excited to hear from the NCA Lights high school student robotics team about their recent entry in the RoboFest Michigan Championship 2017 RoboHit competition. RoboFest is a series of robotics events and competitions organized by Lawrenece Technological University. This year’s baseball-themed competition, “RoboHit”, involved hitting a ping pong ball off of a water bottle with a pencil and circling the outer edge of the arena (base running).
The NCA Lights used a Zumo 32U4 Robot Kit and two 50:1 Micro Metal Gearmotors HPCB 6V with Extended Motor Shaft as the base of their robot.
Pololu customer Alvaro Villoslada made this impressive open-source 3D-printable hand prothesis. Each finger uses a 1000:1 Micro Metal Gearmotor HP 6V with Extended Motor Shaft to wind a fishing line—acting as a tendon—onto a spool. A magnetic encoder attached to each motor enables closed-loop control, and the motors are driven by DRV8838 DC motor driver carriers. An RC hobby servo controls the thumb position. Alvaro uses a Teensy 3.1 microcontroller to monitor the encoders and control the actuators, and he built a user interface in Python for controlling the hand from a computer.
For CAD files, detailed instructions and more pictures and videos, see the Hackaday project page.
MCHobby, a Pololu distributor, translated the Pololu Zumo Shield for Arduino User’s Guide to French as the Guide utilisateur du Robot Zumo Pololu (2MB pdf)! They describe it in French as “Un guide complet pour assembler, utiliser et exploiter rapidement votre Robot Zumo (version 0.1)”. If you’d like to see more translations like this, please let them you know that you enjoyed it and support them by buying from their shop.
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)|
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.
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.
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.
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!