Posts tagged “raspberry pi”
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We are now carrying the Raspberry Pi 3 Model B+. The Raspberry Pi is a popular credit card-sized computer that can run ARM Linux distributions. The Raspberry Pi 3 Model B+ has many performance improvements over the Pi 3 Model B including a faster CPU clock speed (1.4 GHz vs 1.2 GHz), increased Ethernet throughput, and dual-band WiFi. It also supports Power over Ethernet with a Power over Ethernet HAT. Continued…
I am excited to share the second Pololu product for which I routed the PCB, the Dual TB9051FTG Motor Driver for Raspberry Pi. This board complements the TB9051FTG Single Brushed DC Motor Driver Carrier and the recently announced Dual TB9051FTG Motor Driver Shield for Arduino by making it easy to control two motors with a Raspberry Pi (Model B+ or newer).
The TB9051FTG can deliver a few amps across a wide operating voltage (4.5 to 28 V), which makes this expansion board ideal for controlling two small or medium size motors in your Raspberry Pi project. You can optionally connect a voltage regulator, like a D24V10F5 or D24V22F5 step down regulator, to power the Raspberry Pi with your motor power supply. The board also provides a prototyping area to help you construct clean custom circuits without the need for additional prototyping PCBs beyond the footprint of your Raspberry Pi.
The Dual TB9051FTG Motor Driver for Raspberry Pi is available in two versions:
- a partial kit, with connectors included but not soldered in
- fully assembled, with the female header and terminal blocks soldered to the board
The board adheres to the Raspberry Pi HAT (Hardware Attached on Top) mechanical specification, although it does not conform to the full HAT specifications due to the lack of an ID EEPROM. (A footprint for adding your own EEPROM is available for applications where one would be useful.)
With the addition of this product, we now have eight Raspberry Pi motor driver expansion boards for you to choose from. To control more powerful motors, we offer various high-power motor drivers for Raspberry Pi. If you don’t need all the power provided by the TB9051FTG, consider our small and inexpensive DRV8835 Dual Motor Driver for Raspberry Pi or the dual MAX14870 motor driver expansion board (the first board I routed).
We have an introductory discount to go with this new product announcement. The first 100 customers to use coupon code RPITB9051INTRO can get up to two units for just $10.95 each. Note that this introductory offer applies only to the units without connectors soldered in. The introductory coupons for the single TB9051FTG carrier, the dual TB9051FTG Arduino shield, and some other products introduced this year are still available; you can see all the coupons available on our specials page.
For my birthday, I am excited to share two new products to help get your projects moving: dual motor driver boards for Arduino and for Raspberry Pi based on Maxim MAX14870 drivers, which on these boards (without additional cooling) can power motors with a continuous 1.7 A (2.5 A peak) from a voltage source anywhere from 4.5 V to 36 V. This makes the driver ideal for powering a wide range of motors including our high power micro metal gearmotors, and our 12 V 20D mm metal gearmotors. We like the MAX14870 so much that already we make a single driver carrier for it, and we use it on our A-Star 32U4 Robot Controller SV. These new boards make it easy to control two motors using the MAX14870 with an Arduino or Raspberry Pi.
The Dual MAX14870 Motor Driver Shield for Arduino is designed to plug directly into an Arduino or another microcontroller board with the Arduino form factor. It connects the Arduino I/O pins to the two-pin speed/direction interfaces as well as the fault output pins, and our open-source library is available to help you get started. The shield can be set up to power your Arduino device from your motor power supply, which is especially helpful if you are using an Arduino or compatible device with an operating voltage similar to that of the MAX14870, such as our A-Star 32U4 Prime SV. Additionally, the board can be customized to use the advanced features of the MAX14870 drivers or change the pin mappings.
The Dual MAX14870 Motor Driver for Raspberry Pi has many of the same features as the Arduino version, but it is designed to plug into the GPIO header on a compatible Raspberry Pi (Model B+ or newer), including the Pi 3 Model B and Model A+. We provide an open-source Python library to make it easy to interface with the board. This board also has a location to connect a step-down 5 V regulator to power the Raspberry Pi from your motor’s power supply.
I am really excited about these boards because the Raspberry Pi expansion board is the first PCB I ever designed, and the Arduino shield was designed by my friend David S. Both of us are engineering students at the University of Nevada, Las Vegas who work at Pololu to complement our studies. It has been a great experience for us to learn how to design these products from the development engineers here at Pololu. Plus, getting to share these products for the first time with you is a fun way to celebrate my birthday!
As usual for our new product releases this year, we’re offering an extra introductory discount: the first 100 customers to use coupon code MAX14870INTRO can get any mix of up to 3 of these boards for $7.77 each. (Click to add the coupon code to your cart .) Note that this introductory offer applies only to the units without connectors soldered in.
Pi Day is nearly upon us, and to celebrate, we are discounting a variety of exciting products that can be loosely associated with “Pi”. The sale starts tonight at 8:36 PM PDT and runs through the end of the 15th. And in case you are wondering about the strange start time, that makes the sale 3.14159 days long in yet another tribute to this wonderful irrational number (if it bothers you that 3.14159 is not irrational, you can pretend that the sale lasts exactly π days).
This tutorial shows how to build a basic Raspberry Pi robot with the Romi chassis and the Romi 32U4 Control Board, our Arduino-compatible microcontroller board designed specifically for the Romi. With this setup, the powerful Raspberry Pi can take care of high-level tasks like motion planning, video processing, and network communication, while the Romi 32U4 Control Board takes care of low-level tasks that the Pi is incapable of, such as motor control and sensing. Continued…
I am excited to announce the release of the Balboa robot! The Balboa is a two-wheeled balancing robot platform that is small enough to tempt you to run it on a desktop, but it’s quick enough that you should probably stick to bigger, softer surfaces. Or at least put a safety net or foam pit around your desk. Here is a short video showing it kicking up into balancing position and driving around:
A look inside the external gearbox on the Balboa 32U4 Balancing Robot.
One of our main goals in designing our robots is to make them complete and engaging on their own while making them open and expandable enough for all kinds of projects. We also don’t want them all to be the same. Most of the Balboa robots in our pictures have 80 mm wheels, but the chassis can also work with our 90 mm wheels (and to a lesser, barely practical extent, our 70 mm wheels). Because the chassis is made for our micro metal gearmotors, you have a few options for gear ratios as with our Zumo sumo robots, but what’s really exciting about the Balboa design is that there is an extra stage of gear reduction for which you get five different options (all included, and you can easily change the gear ratio from whatever you initially choose). The design also allows the drive wheels to be supported on ball bearings, reducing the stress on the micro metal gearmotor output shafts.
The Balboa chassis has a built-in battery holder for six AA cells, which typically give you several hours of run time, even if you add some extra power-hungry electronics like a Raspberry Pi.
Balboa 32U4 Balancing Robot with battery cover removed.
The main microcontroller is an Arduino-compatible ATmega32U4, which is powerful enough to read the on-board IMU sensors and encoders and to control the motors to balance the robot; it’s also great for introductory projects like line following or reading an RC receiver to make a radio-control balancing robot. For advanced projects, the Balboa is ready for you to add a Raspberry Pi computer to perform high-level algorithms while the ATmega32U4 microcontroller takes care of low-level tasks like motor control.
We will be adding more content to the Balboa’s product page and user’s guide, and we will have more blog posts about the Balboa robot. For today, we’ll end with some slow-motion footage of Balboa popping up on its own and then recovering when Paul knocks it around a bit:
@MarcisShadow is working on a project using a Raspberry Pi with a Pololu DRV8835 Dual Motor Driver Kit for Raspberry Pi to control a Celestron NexStar GoTo Mount, allowing web-based control of a telescope. He also uses a Pololu 5V Step-Up/Step-Down Voltage Regulator S7V7F5 connected to the motor driver to power the Raspberry Pi from the motor power supply.
The project is being documented in a multi-part series on DirtyAstro.com. Part 1 covers the electronics that come with the telescope mount, part 2 is about assembling and testing the DRV8835 driver kit and motors, part 3 tackles setting up the Raspberry Pi and using an SSH client (PuTTY) to connect to it remotely via a PC, and part 4 is about getting Node-Red running to program the Raspberry Pi graphically using a web interface from any machine on the network.
He is not finished with the project, but I have a couple of suggestions for him or anyone doing something similar: First, since his 12 V supply exceeds the maximum operating voltage of both the motor driver (11 V) and the regulator (11.8 V), I would recommend using different ones. Keep in mind that “wall-wart” DC power supplies, especially older transformer-based ones, can have a voltage significantly higher than the rated voltage. Second, a board running a full operating system is usually not great for timing-sensitive operations like counting encoder ticks. If it can’t keep up with the pulse rate, I would recommend using a secondary microcontroller for the encoders. One possibility would be to use the A-Star 32U4 Robot Controller SV with Raspberry Pi Bridge, which incorporates a more appropriate 5.5 V – 36 V regulator, an Arduino-compatible microcontroller, and dual motor controllers.
During Build18 2017, “an annual engineering festival held by the Electrical and Computer Engineering department at Carnegie Mellon University and run by students”, a team of CMU students presented a goldfish-steered mobile fish tank that allows the goldfish to decide where to drive. The robot is controlled by a Raspberry Pi and uses some Pololu parts listed below. They posted a video of the robot on Facebook, and their project webpage has a description and a parts list.
Using an Arduino shield or Raspberry Pi add-on board is often a quick and convenient way to get started on a robotics project, but for maximum flexibility, nothing beats building your own system from standalone boards. Rud Merriam’s Hackaday article describes the design of his Raspberry Pi-controlled robot, for which he opted to use separate modules instead of daughterboards on the Pi, and mentions some of the trade-offs involved in making that decision.
The robot is built on a Wild Thumper chassis and uses a Maestro USB servo controller and two Simple Motor Controllers to interface the Raspberry Pi with the robot’s motors and actuators. In Rud’s writeup, he explains how he made use of some of the more advanced features of the Maestro and SMCs, like using servo channels for general-purpose I/O and setting up daisy-chained serial communications. Check out the full article for all of the details.
We are now offering the Raspberry Pi 3 Model B. The Raspberry Pi is a popular credit card-sized computer that can run ARM Linux distributions. As the successor to the Raspberry Pi 2 Model B, the Pi 3 has a more powerful processor and adds wireless connectivity. Here are the specific improvements:
- 1.2 GHz 64-bit quad-core ARMv8 CPU
- 802.11n Wireless LAN
- Bluetooth 4.1
- Bluetooth Low Energy (BLE)
Along with these improvements, the Raspberry Pi 3 maintains compatibility with and the form factor of the previous Pi 2 (and Pi 1 Model B+). With its 0.1″-spaced GPIO header and small size, the Raspberry Pi also works as a programmable controller in a wide variety of robotics and electronics applications. It can also be combined with our A-Star 32U4 Robot Controller LV with Raspberry Pi Bridge to make a great controller for a small robot. We also carry a selection of Raspberry Pi expansion boards.
This comparison chart can help in selecting the right Raspberry Pi for your project:
Raspberry Pi Model A+ 512MB
Raspberry Pi Model B+
Raspberry Pi 2 Model B
Raspberry Pi 3 Model B
Raspberry Pi 3 Model B+
|CPU speed:||700 MHz||900 MHz||1.2 GHz||1.4 GHz|
|RAM:||512 MB||512 MB||1 GB|
|WiFi:||No||2.4 GHz 802.11n||2.4 GHz 5 GHz 802.11b/g/n/ac|
|Bluetooth Low Energy:||No||Yes|
|Expansion header pins:||40|
|Dimensions2:||2.5″ × 2.2″ × 0.47″||3.35″ × 2.2″ × 0.8″|
|Weight3:||23 g||42 g||50 g|
1 Audio and analog video provided by a single four-pole 3.5 mm jack. This 3.5 mm jack also has its own dedicated low-noise power supply for improved audio.
2 Length and width measurements are for the PCB only; several of the connectors extend past the edge of the board.
3 Weight does not include microSD cards.