via Open Source Hardware – Make: DIY Projects and Ideas for Makers
A group of HAXLR8R graduates say that their modular electric vehicle development kit, FlexPV, will be able to turn almost anything into a motor vehicle. The Kickstarter campaign for FlexPV is replete with crisp graphics and slickly produced videos that show users clamping motor, battery, and control modules to a scooter, a bicycle, and even a […]
LVBots held a line following competition at Pololu on April 16th. The goal was to make an autonomous robot that does three laps of the course the fastest. Seventeen robots faced off in a head-to-head double elimination tournament. The video above shows the robots in action and the full results of the contest.
Ben’sMostly Red Racer won the line following competition for the second time in a row with an average speed of 1.2 m/s, but the competition was more fierce this time. Brandon secured second place with The Chariot, which had an average speed of 1.17 m/s and had a best course time that was only 0.7 seconds slower than Ben’s.
There were also some fun exhibition robots. Kevin made a hovercraft named Full of Eels that was able to sometimes follow the line. Kevin and Jeremy made The Next Level, a line follower on top of a line follower.
Here are posts about some of the robots in the contest:
We now have 40mm-diameter wheels (available in black, red, and white) in the same thin style as our 32×7 mm wheels, which help fill the void between those and the 60×8 mm wheels that were previously our next size up.
Black Pololu wheels with 90, 80, 70, 60, 40, and 32 mm diameters (other colors available).
One of my many roles here at Pololu is overseeing technical support, and I have seen countless cases of customers who have problems with their stepper motor systems because they have not properly set the current limit on their stepper motor driver. To address the issue, we have made a new video that demonstrates how to set the current limit on our stepper motor driver carriers. The video also provides helpful tips and points out a few common pitfalls.
A DRV8825 carrier is used for the demonstration, but the video also applies to our A4988, DRV8824, and DRV8834 stepper motor driver carriers. In the demo, signals for the driver are provided by an Arduino-compatible A-Star 32U4 Prime SV. Here is a simplified version of the Arduino code from the video that can be used to step a motor in both directions:
/* Simple step test for Pololu stepper motor driver carriers
This code can be used with the A4988, DRV8825, DRV8824, and
DRV8834 Pololu stepper motor driver carriers. It sends a pulse
every 500 ms to the STEP pin of a stepper motor driver that is
connected to pin 2 and changes the direction of the stepper motor
every 50 steps by toggling pin 3. */
#define STEP_PIN 2
#define DIR_PIN 3
dirHigh = true;
// Toggle the DIR pin to change direction.
dirHigh = false;
dirHigh = true;
// Step the motor 50 times before changing direction again.
for(int i = 0; i < 50; i++)
// Trigger the motor to take one step.
We have a new video showing several projects you can do with a stock Zumo 32U4 robot. The Zumo 32U4’s motors, encoders, line sensors, proximity sensors, accelerometer, gyroscope, LCD, LEDs, and buttons make it a versatile robot that can be used in a wide variety of projects. The ATmega32U4 microcontroller on the Zumo 32U4 robot can be programmed in C++ from the Arduino IDE.
All of the projects shown in the video use unmodified, stock Zumo 32U4 robots (except for the Zumo driving on the refrigerator, which had strong magnets taped to it). However, you can open up even more possibilities by adding your own electronics to the Zumo 32U4. The FuzzBot, Pixy Pet, and this smartphone-controlled tank are some example projects by our customers that involved adding hardware to our older Zumo Robot for Arduino.
The source code for many of the projects shown in the video is available as examples in Zumo32U4 library, and we are working on adding more of them. Check it out, and get some ideas for a cool Zumo 32U4 project!