Alright, so the robot arm that me and Mark Laatikainen were building is finally finished. After a lot of… adjusting, we managed to finish the prototype successfully. There were some changes to the initial plan, so here’s a summary of our progress.
To control the arm we had planned to use potentiometers because of their simplicity and accuracy. However, we were presented with the possibility to use a Nunchuk (the Wii remote that is), so we just had to take the chance.
Nunchuks are fitted with an accelerometer that can measure motion and tilting. We decided to connect the Nunchuk to the two main servos that do the heavy lifting. So now when you tilt the controller horizontally or vertically the arm responds. One of the biggest problems we encountered with the accelerometer were the uneven values it provided. We had to implement a sliding average into the code and some if/else- conditions to filter out the erroneous values. The arm is still a bit “jittery” because of the faulty values but it’s manageable.
We use four servos in the arm and we couldn’t connect them all to the accelerometer. So we allocated the analog stick to the third servo and the fourth servo, that controls the “claw”, to the trigger button “Z”. The controls work fairly well with this configuration.
Here are some pictures of the final setup:
I had a lot of fun with this project and I’m glad I got to work on it with Mark, who’s a very capable programmer and very competent with electronics. Mark uploaded the code for the arm on his GitHub-page. Here is a list of the parts we used:
I’m attending a second course based on Arduino development. The objective is to build a prototype in five days. This time I’ve partnered up with Mark Laatikainen and together we’re building a controllable robot arm.
We decided to use Tower Pro micro servos and potentiometers to control the servos. At first, joysticks seemed like the best choice, but we switched to potentiometers because of their simplicity.
Here are some pictures of the early build and a quick video:
I’m currently attending a course on making IOT-devices using Arduino Uno, a simple microcontroller board. The objective is very simple: create a functional embedded system that uses the internet in some manner, a.k.a make an IOT-device (IOT=Internet Of Things). As a complete beginner to programming, electronics and, well, the internet, this course has proven quite challenging to me. However, I’m lucky to have a helpful and patient teacher (Tero Karvinen) and many fellow students that are willing to assist.
On the course we work in pairs. As a project me and my teammate (Tomi Laakkonen) chose to create a RGB LED lamp that changes color with the temperature in Helsinki. We named it “weatherlamp” (yes, quite original). In short, we programmed the Arduino board to fetch the current outdoor temperature from Openweathermap and depending on the degree, the RGB LED changes its color. The project really is quite simple but I at least have learned an immense amount about programming and the basics of IOT.
I’m still in the middle of the project but I will be posting the finished results here. In the meanwhile you can check out the course coordinated by Tero Karvinen here, I heartily recommend it: