Question

Please answer the following questions:

Consider the IMU unit which has 9 degrees of freedom.

1. What data type is required to store the accelerometer, gyroscope and magnetometer samples i.e. byte, int or long?
2. What is the rate of data generation if the IMU unit is sampled at 100Hz? Determine if the baud rate of 9600 with 8 bits, no parity and 1 stop bit is sufficient for transmitting the data at the same generation rate.

Thank you :)

Answer 1

ANS-a:

The 9 DOF ( degree of freedom) is a very small sensor board with 9 degree of freedom which uses a byte datatype. This data type can be useful for saving memory in large scaling area.

Accelerometer are used to sense both static and dynamic i.e gravity and sudden start/stops accelerations. The upper and lower limits of what the accelerometer can measure is know as its range. Good accelerometer with maximum ranges  stretching from ±1g to ±250g. Most of our accelerometers are set to a hard maximum/minimum range, however some of the fancier accelerometers feature selectable ranges.

Gyroscope measures angular velocity, how fast something is spinning about an axis.If you're trying to monitor the orientation of an object in motion, an accelerometer may not give you enough information to know exactly how it's oriented. Unlike accelerometers gyros are not affected by gravity, so they make a great complement to each other.

Mangnetometer measured orientation to magnetic north , on the x, y, and z axes. Therefore, we can calculate which direction we are facing as the angle at which we are learning.

Gyroscope and accelerometers are great, but alone they do not give you quite enough information to be able to comfortably calculate things like orientation, position, and velocity. To measure those and other variables many people combine the two sensors, to create an inertial measurement unit (IMU).