Tag Archives: robotpi

Boston Dynamics’ Handle robot recreated with Raspberry Pi

Post Syndicated from Ashley Whittaker original https://www.raspberrypi.org/blog/boston-dynamics-handle-robot-recreated-with-raspberry-pi/

You in the community seemed so impressed with this recent Boston Dynamics–inspired build that we decided to feature another. This time, maker Harry was inspired by Boston Dynamics’ research robot Handle, which stands 6.5 ft tall, travels at 9 mph and jumps 4​ ​feet vertically. Here’s how Harry made his miniature version, MABEL (Multi Axis Balancer Electronically Levelled).

MABEL has individually articulated legs to enhance off-road stability, prevent it from tipping, and even make it jump (if you use some really fast servos). Harry is certain that anyone with a 3D printer and a “few bits” can build one.

MABEL builds on the open-source YABR project for its PID controller, and it’s got added servos and a Raspberry Pi that helps interface them and control everything.

Installing MABEL’s Raspberry Pi brain and wiring the servos

Thanks to a program based on the open-source YABR firmware, an Arduino handles all of the PID calculations using data from an MPU-6050 accelerometer/gyro. Raspberry Pi, using Python code, manages Bluetooth and servo control, running an inverse kinematics algorithm to translate the robot legs perfectly in two axes.

Kit list

If you want to attempt this project yourself, the files for all the hard 3D-printed bits are on Thingiverse, and all the soft insides are on GitHub.

IKSolve is the class that handles the inverse kinematics functionality for MABEL (IKSolve.py) and allows for the legs to be translated using (x, y) coordinates. It’s really simple to use: all that you need to specify are the home values of each servo (these are the angles that, when passed over to your servos, make the legs point directly and straight downwards at 90 degrees).

When MABEL was just a twinkle in Harry’s eye

MABEL is designed to work by listening to commands on the Arduino (PID contoller) end that are sent to it by Raspberry Pi over serial using pySerial. Joystick data is sent to Raspberry Pi using the Input Python library. Harry first tried to get the joystick data from an old PlayStation 3 controller, but went with the PiHut’s Raspberry Pi Compatible Wireless Gamepad in the end for ease.

Keep up with Harry’s blog or give Raspibotics a follow on Twitter, as part 3 of his build write-up should be dropping imminently, featuring updates that will hopefully get MABEL jumping!

The post Boston Dynamics’ Handle robot recreated with Raspberry Pi appeared first on Raspberry Pi.

Auto-blow bubbles with a Raspberry Pi-powered froggy

Post Syndicated from Ashley Whittaker original https://www.raspberrypi.org/blog/auto-blow-bubbles-with-a-raspberry-pi-powered-froggy/

8 Bits and a Byte created this automatic bubble machine, which is powered and controlled by a Raspberry Pi and can be switched on via the internet by fans of robots and/or bubbles.

They chose a froggy-shaped bubble machine, but you can repurpose whichever type you desire; it’s just easier to adapt a model running on two AA batteries.

Raspberry Pi connected to the relay module

Before the refurb, 8 Bits and a Byte’s battery-powered bubble machine was controlled by a manual switch, which turned the motor on and off inside the frog. If you wanted to watch the motor make the frog burp out bubbles, you needed to flick this switch yourself.

After dissecting their plastic amphibian friend, 8 Bits and a Byte hooked up its motor to Raspberry Pi using a relay module. They point to this useful walkthrough for help with connecting a relay module to Raspberry Pi’s GPIO pins.

Now the motor inside the frog can be turned on and off with the power of code. And you can become controller of bubbles by logging in here and commanding the Raspberry Pi to switch on.

A screenshot of the now automated frog in situ as seen on the remo dot tv website

To let the internet’s bubble fans see the fruits of their one-click labour, 8 Bits and a Byte set up a Raspberry Pi Camera Module and connected their build to robot streaming platform remo.tv.

Bubble soap being poured into the plastic frog's mouth
Don’t forget your bubble soap!

Kit list:

The only remaining question is: what’s the best bubble soap recipe?

The post Auto-blow bubbles with a Raspberry Pi-powered froggy appeared first on Raspberry Pi.