Indoor navigation robot update

It has been some time since a worked on this robot. This is a video of me building and installing the main PCB on the robot. The video was actually recorded several months ago, but now I recently found the inspiration to continue to work on this project.

The main board has an Arduino Due that controls the two stepper motors that drive the wheels. The PCB also has a lot of other features including servo outputs/inputs, MOSFET outputs, bumper sensor inputs, 6 DOF IMU (gyro and accelerometer), a few buttons and LEDs, and a couple of other things. In the video, I connect an RC receiver the servo inputs on the board and drive the robot abound using remote control.

The future plans for this robot are to implement a serial interface in the Arduino Due, and then connect it the Rasberry Pi. That way the Rasberry Pi will be able the drive the stepper motors and also read data from the IMU and other sensors. Then I can make a python script or something running on the Pi that gives the robot some interesting behaviors.

I also plan a replacing the Time Of Flight LIDAR sensor mounted on the stepper motor seen in the video with a rotating Laser sensor instead. The problem with the Time Of Flight sensor is that it has a very limited range and sampling time. I recently found out about the rotating Laser Distance Sensor (LDS) used on Xiaomi robot vacuum cleaner robots. It is available for cheap as a replacement part the vacuum robots. There is also an open source project to control the spinning of the sensor an read data from it, which should make it relatively easy to connect to the Rasberry Pi in my robot.

GPS navigation robot – Two waypoints

This video shows a robot I have built that is driving between two waypoints using GPS.

I built this robot last summer, about a year ago. Back then, I never really managed to the software part of the robot working. The weather became worse outside as the fall came, and a lost interest in this project and started working on other things instead.

I wave written all the code myself, apart from the functions used to calculate course and distance between GPS waypoints. I used functions from the TinyGPS library for that. The code runs on an Arduino Due, the robot is using PID control to steer towards the waypoints. The robot uses a combination of GPS-course and integrating the signal from a yaw-gyro to determine its current course. The robot also has a compass, but it does not seem to work very reliably, therefore I do not use it. The robot also has sonar and other sensors, but they are not used in this video. Expect more videos and info about this robot in the near future.

Paramotor test flight

A short video of a DIY paramotor trike that I have built using the Hobbyking parafoil. This video was shot during the first successful test flight. I made a few unsuccessful attempts before I got it working. It still needs a few adjustments. The tricky part is to get all the lines of the parafoil to the correct lengths relative to each other. This is important because it needs to have the correct shape, as well as the correct angle of attack. I will probably write more about it and make a better video when I am more satisfied with how it flies.

Click “continue reading” below for a few images.

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New robot project

This is a new long-term robot project I have been working on for the past couple of months. It is a general purpose indoor robot, that will work as a platform for experimentation. When designing this robot, I have tried to think about and improve everything I have learned from previous robot projects I have made. But this robot will also feature some new stuff I have not tried before. Some of the key features if the robot includes:

  • Stepper motor based four-wheel-drive skid-steering drive system
  • Big Li-Ion battery
  • A lot of custom 3D printed parts
  • Heavy duty bumpers, large ground clearance and large foam wheels
  • Raspberry Pi main computer
  • Arduino Due for controlling low-level peripherals
  • Scanning Lidar sensor
  • Probably a Raspberry Pi camera module mounted on a pan/tilt system

So far, only the majority of the mechanical work is done. Here are a few images, click on them to make them larger:

DIY 3D printer detailed overview

This video is a detailed overview of my DIY coreXY 3D printer. It is just over a year since I built it. Some things have changed since then, but most of the machine it the same. This is my first and only 3D printer, I use a few times a week, sometimes more often than that. The printer works very well, it produces high-quality parts while requiring very little maintenance.

Link to 3D printer page: DIY 3D printer