Hello everyone welcome back to our blog. A lot of groups have been affected by this problem and our group is no exception. But what is this problem I am talking about? The problem is motors suddenly not turning or suddenly jerking or skipping. Now this is a huge problem as almost all of our projects are relying on motors to turn propellers to provide thrust for movement. Originally we set our motors PWM to 255 ( The maximum pulse width modulation) this means we are supplying our motors with the maximum amount of voltage our power supply can provide, in our case we are using a 12v LiPO battery. This provided much speed in air but when we put it in to the water our motors started stalling and skipping. We asked around and found out that alot of other groups were facing the same problem and were stumped. We researched online and found out that propellers for airplanes are able to turn very fast as air resistance is quite small compared to water resistance hence the propellers in water needs to turn slower. However this does not mean that the motors become less powerful. They actually become more powerful as the lesser the speed the greater the torque. We then set our PWM to 100 and voila our motors started to turn without Stalling Jerking or Skipping. PWM is a tool by Arduino to change the output voltage. PWM or pulse width modulation means controlling the pulse width to achieve a lower voltage. The formula is (Max Voltage) x (The time the wave is HIGH / The Period of a wave). The image below shows a example of pulse width modulation in action.
Thank you for reading and we hoped that this blog post have helped you solve your problem.
No comments:
Post a Comment