Posts by Kevin
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We’ve updated our USB Micro-B Connector Breakout Board with some minor improvements that should make it a little nicer to work with.
On the original version, the mounting cutouts didn’t work as well as we wanted: they were shallow, and the board was often prone to slipping out of place between two screws. The new version is wider and its cutouts are deeper to allow for more secure mounting, and it is slightly shorter in the other direction (0.4″ × 0.6″ with the connector).
For more information, see the board’s product page.
Our micro metal gearmotors are now available in 12 V versions! These high-power motors have long-life carbon brushes (HPCB) and offer the same performance as the 6 V HPCB motors at their respective nominal voltages; the only difference is that the 12 V motor draws half the current at twice the voltage.
The new 12 V gearmotors are available across our usual range of 11 gear ratios and in single- and dual-shaft versions. Along with our existing selection of micro metal gearmotors, this brings the total number of unique options available to 107:
@ Rated Voltage
@ Rated Voltage
@ Rated Voltage
(Gearbox & Motor)
|800 mA||6000 RPM||2 oz-in||5:1 HPCB 12V||5:1 HPCB 12V dual-shaft|
|3000 RPM||4 oz-in||10:1 HPCB 12V||10:1 HPCB 12V dual-shaft|
|1000 RPM||9 oz-in||30:1 HPCB 12V||30:1 HPCB 12V dual-shaft|
|625 RPM||15 oz-in||50:1 HPCB 12V||50:1 HPCB 12V dual-shaft|
|400 RPM||22 oz-in||75:1 HPCB 12V||75:1 HPCB 12V dual-shaft|
|320 RPM||30 oz-in||100:1 HPCB 12V||100:1 HPCB 12V dual-shaft|
|200 RPM||40 oz-in||150:1 HPCB 12V||150:1 HPCB 12V dual-shaft|
|140 RPM||50 oz-in||210:1 HPCB 12V||210:1 HPCB 12V dual-shaft|
|120 RPM||60 oz-in||250:1 HPCB 12V||250:1 HPCB 12V dual-shaft|
|100 RPM||70 oz-in||298:1 HPCB 12V||298:1 HPCB 12V dual-shaft|
|32 RPM||125 oz-in||1000:1 HPCB 12V||1000:1 HPCB 12V dual-shaft|
We’ve updated our Wixel Shield for Arduino with a few minor improvements. The Wixel Shield provides an easy way to connect a Wixel wireless module to your Arduino or A-Star 32U4 Prime, enabling wireless communication and even wireless programming (on some Arduinos). However, the original version of the shield was released many years ago, so it was not designed with the modern pinout of the Arduino Uno R3 in mind.
The Wixel Shield v1.1 adds pass-throughs for the four new pins—SCL, SDA, IOREF, and an unused pin—introduced by the R3 and present on all newer Arduinos, making it easier to stack other shields with it (especially ones that make use of the new I²C pin location). It also features improved level shifter circuits that make use of the IOREF voltage provided by the Arduino, allowing the shield to work automatically with both 5 V and 3.3 V Arduino boards.
The Wixel Shield for Arduino v1.1 is available by itself and as part of a combination deal that includes a pair of Wixels and a USB cable. See the user’s guide for the shield for additional information.
Our second-generation family of high-power motor drivers continues to grow with the release of our G2 High-Power Motor Driver 18v25 and G2 High-Power Motor Driver 24v21, discrete MOSFET H-bridges that can supply a brushed DC motor with up to 25 A of continuous current at up to 30 V or up to 21 A of current at up to 40 V, respectively. In addition, we’ve lowered the prices of the 18v17 and 24v13 versions to make them even more affordable.
The new G2 18v25 and G2 24v21 drivers’ double-sided design allows them to retain the same board dimensions as their 18v17 and 24v13 siblings, even though they can deliver significantly more power. The G2 drivers are half an inch shorter and can handle the same (or slightly more) current compared to the original 18v25 and 24v20 they are designed to replace, and they are less than half the size of the original 18v25 CS and 24v23 CS while offering basic current sensing functionality that can eliminate the need for a dedicated current sensor in some applications. As with previous G2 drivers, they also include reverse-voltage protection and a current limiting feature.
Pololu G2 High-Power Motor Driver 24v21 next to original high-power motor driver 24v20 and 24v23 CS.
Pololu G2 High-Power Motor Driver 24v21 and 24v13.
For more information about the G2 motor drivers, see their product pages at the links below.
Our A-Star 32U4 Robot Controller SV with Raspberry Pi Bridge is now available, joining the LV version we released six months ago.
Similar to its lower-voltage sibling, the Robot Controller SV is a general-purpose robot controller that includes dual motor drivers and other useful peripherals like pushbuttons and a buzzer. It also has the same level shifters and power circuit that allow it to easily power and communicate with a Raspberry Pi when mounted as an auxiliary controller. Like our other A-Star controllers, the A-Star Robot Controller SV built around an ATmega32U4 microcontroller and ships preloaded with an Arduino-compatible USB bootloader.
This SV version of the A-Star Robot Controller uses an efficient step-down switching regulator, enabling it to operate (and optionally supply power to an attached Raspberry Pi) with input voltages from 5.5 V to 36 V. Compared to the LV version, the Robot Controller SV can also supply substantially more current across its wide operating voltage range:
We’ve been working on some (long-awaited) I²C software to allow the A-Star to be used as a slave controller with a Raspberry Pi master, as well as an example project that shows how to build a robot with this setup. They’re nearly ready, so watch for them on the blog in the coming weeks. But don’t forget that the A-Star board can also be used by itself as a capable robot controller, as my recent sumo robot demonstrates.
To facilitate both of these uses, the A-Star 32U4 Robot Controller SV is available either assembled for use as a Raspberry Pi add-on or in a more barebones configuration that is suitable for customized assembly or standalone use. See those product pages and the user’s guide for more information about the robot controller.
As with other ST sensors, these chips can be configured and read through I²C or SPI interfaces, and our compact breakout boards incorporate voltage regulators and level shifters to make them easier to use with 5 V systems. Compared to the inertial and magnetic sensors we’ve used previously (most recently the LSM303D accelerometer and magnetometer and the L3GD20H gyro), these two new ICs offer different combinations of capabilities: the LSM6DS33 integrates an accelerometer and rate gyroscope into a single package, while the LIS3MDL is a standalone magnetometer.
For more information about these boards, see their product pages at the links below.
We now have three "Pi"s! …No, I’m not talking about our 3pi robot.
In addition to the Raspberry Pi Model B+ we’ve been carrying, we now offer the smaller Raspberry Pi Model A+ and the more powerful Raspberry Pi 2 Model B as well. Check out their product pages for details about each version and how they compare to each other.
Raspberry Pi Model B+.
As with the B+, the A+ and 2 B are compatible with our Raspberry Pi expansion boards, including our A-Star 32U4 Robot Controller with Raspberry Pi Bridge and our MC33926 and DRV8835 motor driver add-ons.
This discrete MOSFET H-bridge can supply a brushed DC motor with up to 17 A of continuous current at voltages between 6.5 V and 30 V. Compared to its predecessor, the G2 driver handles a little more current and offers features like reverse-voltage protection, current sensing, and current limiting. For more information, see its product page.
Robot enthusiasts: if you want to show your Pololu pride but covering yourself with Pololu stickers just doesn’t seem fashionable, we’ve got good news for you! Our new Zumo T-shirts are here, featuring a Zumo 32U4 robot within a sprocket-inspired border, accompanied by our call to “Engage Your Brain”. These pre-shrunk cotton shirts are available in several colors (royal blue, cardinal red, or charcoal gray) and a range of sizes.
My robot, Roku, was the champion of LVBots’ August mini-sumo competition. While I didn’t have the time or inspiration to make it look like anything more interesting (like a Star Wars droid) or make use of especially innovative tactics, I think I managed to build a robot that not only is effective but also looks fairly clean and well put together. In addition, it’s a good demonstration of how the Pololu A-Star 32U4 Robot Controller can be used as a standalone main board for a small robot. Continued…