Specifications

Figure 5: 2DOF HELI subsystem contains QUARC blocks that interface with hardware
7. The voltage sent to the Analog Output block is amplified by the amplifiers and applied to the power
amplifier’s attached motor. Note that the control input is divided by the amplifier gain, K_AMP, before
being sent to the DAQ board. This way, the amplifier gain does not have to be included in the
mathematical model as the voltage output from the controller is the voltage being applied to the motor.
The amplifier and DAQ saturation blocks limit the amount of voltage that can be fed to the motor.
8. Open the theta (deg), psi (deg), and Vm (V) scopes in the Scopes folder. These scopes display both the
desired and measured angles of the Helicopter as well as the voltages being applied to the front and back
motors.
9. Ensure the helicopter has been setup and all the connections have been made as instructed in the 2DOF
Helicopter User Manual.
10. Turn ON the amplifier. For the VoltPAQ-X2, the green LED on the amplifier should be lit.
11. 11. In the q_heli_2d_open_loop Simulink diagram, make sure the Program/Joystick block shown in Figure
5.15 is set to 2 in order to generate the desired voltage from the joystick.
12. Click on QUARC j Build to compile the code from the Simulink diagram.
13. Select QUARC j Start to begin running the controller.
14. Try to bring the helicopter body to a horizontal by pulling the joystick handle toward you.This supplies a
positive voltage to the pitch motor and causes the pitch angle to increase
15. As depicted in Figure 5.17, you will notice that the yaw angle moves clockwise in the positive direction as
the voltage in the pitch motor increases. Compensate for this coupling effect by moving the joystick arm
to the left and apply a negative voltage to the yaw motor. As illustrated, the pitch is eventually stabilized
at about 0 degrees when the pitch motor voltage is approximately 12.5 V and the yaw begins to stabilize
when feeding a voltage of about -6.0 V to the yaw motor.
16. From this point, now try decreasing the yaw voltage and observe its effect on the pitch angle.