Gyro choices???
Gyro choices???
by quickster47
Fri Sep 28, 2007 11:35 am
In my search of all things Robonova across the vast Internet I noticed that most owners of the Robonova, and other humanoids, have used the GWS PG03 piezo gyro system. It is sort of like the de facto standard.
And I am wondering if this is because of price.
So whilst waiting for my Robonova to arrive I ordered a pair of the GWS PG03s but I also ordered a pair of the Futaba G190 micro piezo gyros. Since I fly electric helicopters I have pretty much always used Futaba servos and gyros so I decided to give their small rate gyros a try. I know one of the Futaba gyros cost about the same as two of the GWS gyros so I am thinking price is the reason for them not showing up on the different humanoids.
Has anyone tried or used the Futaba G190 micro piezo rate gyros and if so, how did they perform?
Carl
And I am wondering if this is because of price.
So whilst waiting for my Robonova to arrive I ordered a pair of the GWS PG03s but I also ordered a pair of the Futaba G190 micro piezo gyros. Since I fly electric helicopters I have pretty much always used Futaba servos and gyros so I decided to give their small rate gyros a try. I know one of the Futaba gyros cost about the same as two of the GWS gyros so I am thinking price is the reason for them not showing up on the different humanoids.
Has anyone tried or used the Futaba G190 micro piezo rate gyros and if so, how did they perform?
Carl
by i-Bot
Sat Sep 29, 2007 9:38 am
I can only comment for the RoboNova.
The RoboNova is very specific about the Gyros that are supported: the PG-03 and the KRG-1.
The way the Gryo is used is different from in a helicopter. In the helicopter the gyro sits between the receiver and the servo. It takes the position pulse from the receiver and outputs a modified servo pulse based on the input pulse and the gyro output. In the RoboNova the controller outputs a fixed length pulse and then receives back a modified pulse which represents the gyro output. This pulse is measured to give a value, which is then used to modify the servo position, using the direction and the sensitivity. To achieve this it makes use of a known relationship between the input and output pulse for both types of supported Gyro. This relationship changes fo different gyros, and while not important for helicopters, would prevent other gyros working with th RoboNova, unless they had the exact same relationship of input to output.
You may be lucky, but I think I recall the Futaba did not work from other posts.
Given how the Gyro is used in the RoboNova, I doubt if a better quality Gyro is justified. I think the way forward is with a proper IMU.
The RoboNova is very specific about the Gyros that are supported: the PG-03 and the KRG-1.
The way the Gryo is used is different from in a helicopter. In the helicopter the gyro sits between the receiver and the servo. It takes the position pulse from the receiver and outputs a modified servo pulse based on the input pulse and the gyro output. In the RoboNova the controller outputs a fixed length pulse and then receives back a modified pulse which represents the gyro output. This pulse is measured to give a value, which is then used to modify the servo position, using the direction and the sensitivity. To achieve this it makes use of a known relationship between the input and output pulse for both types of supported Gyro. This relationship changes fo different gyros, and while not important for helicopters, would prevent other gyros working with th RoboNova, unless they had the exact same relationship of input to output.
You may be lucky, but I think I recall the Futaba did not work from other posts.
Given how the Gyro is used in the RoboNova, I doubt if a better quality Gyro is justified. I think the way forward is with a proper IMU.
by quickster47
Sat Sep 29, 2007 3:50 pm
Hey i-Bot,
Thanks so much for the explanation and information on how the RN-1 handles and makes use of the gyro. It would have surely taken me a while to figure that one out.
I will get out my o-scope and see how the Futaba gyro works with the RN-1 even though it may be an exercise in futility.
Glad I went ahead and got the GWS gyros now.
Carl
Thanks so much for the explanation and information on how the RN-1 handles and makes use of the gyro. It would have surely taken me a while to figure that one out.
I will get out my o-scope and see how the Futaba gyro works with the RN-1 even though it may be an exercise in futility.
Glad I went ahead and got the GWS gyros now.
Carl