# 9-Axis IMU LESSON 25: Proportional Control System for Self Leveling Platform

In this lesson we improve our earlier control system for our self leveling platform. In our earlier work, our control system would elliminate system error by constant corrections of 1 degree each time through the loop. In this lesson, we show how to feedback a control signal that is proportional to the error. Hence larger errors will get a larger correction signal, and the error is driven to zero much quicker.

This is the code we developed during this lesson:

# 9-Axis IMU LESSON 24: How To Build a Self Leveling Platform with Arduino

In this lesson we develop the initial simple code for leveling the platform. We implement the simplest control system, which is to just increment or decrement the servos based on whether the actual position is greater or less than the target position. We increment/decrement by one degree, since this is the smallest allowed change in servo position. Next week we will implement a more sophisticated control system. Below is the arduino code developed in this lesson.

# 9-Axis IMU LESSON 23: Self Leveling Platform Using BNO055 and Arduino Controlled Servos

In this lesson we connect the circuit and do the mechanical build for our self leveling platform. You can see a list of the gear we are using in LESSON 22.

# 9-Axis IMU LESSON 22: How to Create a Tilt Stabilized Platform with Arduino

In this Lesson we begin to work on developing a tilt stabilized platform using the BNO055 9-axis sensor, and we will take advantage of all the learning that happened in the first 22 lessons. Now though, we will be moving out of the virtual world of Vpython, and will begin working in the real world. In this lesson we focus on getting the gear together. You can go ahead and order your gear, and then next week we will begin assembling and coding. In addition to the arduino nano, and the BNO055, you will need:

You Will Need Two of These HiTEC Servos

NOTE: I am no longer recommending the MG995 four pack of servos, as I have recently gotten several bad batches, so have moved to the HiTEC linked above.

A set of Pan Tilt Brackets:

PC Board Power Supply (If you have the ELEGOO Kit, you already have this)

Good Wall Wart Power Plug for the Power Supply (if you dont have one)

Bundle of Extra Cables

OK, get your gear ordered and we will start putting things together next week.

# 9-Axis IMU LESSON 20: Vpython Visualization of Roll, Pitch, and Yaw

This is the arduino code we developed in this lesson to approximate roll, pitch and yaw over small ranges.

This is the python code we developed to visualize the 3 dimensional rotation of a rigid body.