Pololu Blog (Page 14)
Welcome to the Pololu Blog, where we provide updates about what we and our customers are doing and thinking about. This blog used to be Pololu president Jan Malášek’s Engage Your Brain blog; you can view just those posts here.
It has been snowing on and off today in Las Vegas, but luckily the weather was not bad enough to delay our last product release of 2014: the A-Star 32U4 Prime SV. We hope that this and the other A-Stars we released this year will help bring success to your projects in 2015. Thanks for your business and support in 2014, and Happy New Year!
The A-Star 32U4 Prime SV, our newest A-Star, is an Arduino-compatible board with a switching regulator that allows an input voltage range of 5 V to 36 V. Like the A-Star 32U4 Prime LV we released earlier this month, the A-Star 32U4 Prime SV shares the pinout and form factor of the Arduino Leonardo and should work with compatible shields.
What really sets the A-Star 32U4 Primes apart from competing products is their power supply system based on high-efficiency switching regulators, which allow plenty of power to drive your microcontroller and lots of peripherals over a large range of input voltages. The A-Star 32U4 Prime SV uses the Intersil ISL85410 1-Amp buck regulator, a more powerful relative of the regulator on A-Star 32U4 Mini SV. So you get 1 A at 5 V over most of the SV input voltage range. (We recommend an input voltage of at least 6 V.) And since a switching regulator draws less current as the voltage increases, you can get a lot more out of higher-voltage power supplies and battery packs. In a typical usage scenario, if you power your project with a 12 V battery, the A-Star 32U4 Prime SV will draw about half the current of a competing product with a linear regulator – and last twice as long on a single charge.
|A-Star 32U4 Prime power distribution diagram.|
Like the A-Star 32U4 Prime LV, the SV has a bunch of features designed to make it easy for you to make use of the power. The TPS2113A USB power mux allows you to safely and seamlessly switch between a battery and USB power (up to 1.5 A using a powerful enough USB supply), without the limitations of diodes or fuses. We included a handy power switch for your external power input, extra connection options in case you don’t want to use the standard DC power jack, extra access points for the important power nodes VIN, VREG, 5V, and 3V3, and big power and ground buses.
The A-Star 32U4 Prime SV includes all the same peripheral features as the A-Star 32U4 Prime LV: battery voltage monitoring, three user pushbuttons (sharing the MISO, RXLED, and TXLED lines), a buzzer optionally controlled by digital pin 6, a connector for an HD44780-based character LCD, and – on some models – a microSD card slot that works with the Arduino SD library. Here is an SV with all the optional peripherals installed:
You can purchase this configuration pre-assembled as Pololu item #3115, or get it with almost everything but the LCD as Pololu item #3114. (You can still install an LCD yourself later.) For other configuration options, please see the individual product pages below or the A-Star 32U4 Prime SV category page.
Forum member jr1985 posted about Sparky, a robot that uses a Micro Maestro and custom Visual Basic software running on a laptop. The goal is for sparky to one day become an assistive companion robot that entertains and helps elderly or disabled people. Currently, Sparky is able to avoid obstacles and navigate through rooms while logging movements to map the areas it encounters. And it has some dancing skills:
For all the Sparky videos, take a look at jr1985’s YouTube channel.
Happy Holidays everyone! I thought it would be fun to share this sumo bot that features Darth Vader/Santa Claus and uses our Zumo chassis.
Erich has also posted to our forum about his projects before; you can find a list of the forum posts he made that we blogged about below:
March 2013: Zumo Robot with FRDM-KL25Z Board
September 2013: Zumo Robot with Pololu Plug-in Modules
October 2013: Zumo Robot with Pololu Plug-in Modules, assembled
December 2013: Zumo Tournament Videos
We will be closed for Christmas on Thursday, December 25 and for New Year’s Day on Thursday, January 1, so orders placed after 2 PM Pacific Time on the 24th or 31st will be shipped on the following Friday. Additionally, FedEx Ground does not ship on the 24th (today).
Merry Christmas and Happy New Year!
This new stepper motor bracket is designed to work with typical NEMA 14-size stepper motors, including all of the NEMA 14 stepper motors we carry. It is made from 2mm-thick black anodized aluminum, and like the larger NEMA 17 bracket we released earlier this year, it features slot cutouts to allow for a variety of mounting options.
For more information, see the product page.
In case you missed our Black Friday Sale or are just looking for a last-minute deal before Christmas, check out our year-end inventory reduction sale!
The A-Star 32U4 Prime LV is the newest member of our A-Star family of programmable microcontroller boards. This is the first Pololu board with the familiar Arduino shape: it shares the pinout of the Arduino Leonardo and should work with Leonardo-compatible shields. With some code changes, this A-Star can also serve as a substitute for the similar Arduino Uno in many projects. However, there is a lot more to it than Arduino compatibility!
Unlike the Uno and Leonardo, the A-Star Prime has an efficient 5 V switching regulator and a seamless USB power switching circuit. This “LV” model uses the same power circuit, based on the Texas Instruments TPS63061 and TPS2113A, as the A-Star 32U4 Mini LV. Like that board, the A-Star 32U4 Prime LV can operate from 2.7 V to 11.8 V and supply about 1 A at 5 V, safely and efficiently switching between USB and external power without the limitations of components like fuses or diodes. It also includes a power switch, multiple power input connection points, and optional battery voltage monitoring, making it convenient to use in a variety of power supply scenarios. Here is a diagram of power distribution on the board:
As you can see in the pictures, there are few extra rows of pins next to the normal Arduino headers. The point of these is to give you more connection options: we have included an extra access point (on a 0.1" grid) for most of the pins, as well as extra power and ground buses. The power buses are unconnected by default, so you could, for example, wire VIN directly to a bus and solder in servo connectors in one place (the LV regulator works great on a four- or five-cell NiMH pack), while having another bus run at 3.3 V to power an array of low-voltage sensors. As another example, these buses are a convenient place to add your own custom pull-up or pull-down resistors.
There is a lot of space available in this form factor compared to the typical Pololu breakout board, and we hate to waste space, so we packed it with extra, optional peripherals:
You might recognize some of the optional peripherals from our line of Orangutan Robot Controllers and the 3pi Robot. These are features that we have found really handy in our projects over the years: three user pushbuttons (sharing the MISO, RXLED, and TXLED lines), a buzzer for beeps and simple music (optionally controlled by digital pin 6), and a connector for an HD44780-based character LCD. You can enable just the features you want with jumpers; the ones you do not use will not interfere with shields or other electronics. On some models, we are also including a microSD card slot that works with the Arduino SD library, so you can easily turn your A-Star Prime into a datalogger or access large scripts and media files.
Here is what the A-Star 32U4 Prime LV looks like with all optional peripherals installed:
This configuration is available pre-assembled as Pololu item #3109, while a configuration including pretty much everything but the LCD is available as Pololu item #3108. (You can still install an LCD yourself later.) For other configuration options, please see the individual product pages below or the A-Star 32U4 Prime LV category page.
We just released 3.3 V, 6 V, 7.5 V, and 9 V versions of our D24V25Fx regulators, previously available only in a 5 V version. The D24V25x is a family of step-down regulators that take an input voltage as high as 38 V and have a typical maximum output current around 2.5 A. For more information, take a look at one of the items listed below or check out our step-down voltage regulators category page.
|Sharp GP2Y0A51SK0F Analog Distance Sensor 2-15cm with wires soldered directly to the sensor PCB.|
We are now carrying the short-range Sharp GP2Y0A51SK0F Analog Distance Sensor. Like the GP2Y0D815Z0F we released a few months ago, this sensor has a maximum intended sensing range of 15 cm, but unlike that other sensor, this module tells you where the detected object is in its 2 cm to 15 cm range. Its close minimum sensing distance of 2 cm and high 60 Hz update rate make this a great choice for close-proximity range-finding, or the analog voltage output can be passed through a comparator to make an adjustable-threshold alternative to our digital Sharp distance sensors.
This sensor uses a 1.5 mm pitch JST ZH connector, which is different from the connectors on all the other Sharp sensors we carry. Unfortunately, this means it will not work with the JST PH cables we recommend for use with some of those other sensors. We are working on getting compatible cables, but in the interim, it is not too difficult (but not exactly easy) to solder wires directly to the output pins like in the picture on the right.
This sensor is also quite a bit smaller than most of the other analog Sharp sensors, so it will not work with our new brackets.
|A variety of Sharp distance sensors. From left to right: GP2Y0A02, GP2Y0A21 or GP2Y0A41, GP2Y0A51, and GP2Y0D8xx.|
For more information, see the GP2Y0A51SK0F product page.