What is duty cycle?

[starsROBOTICS]

I was reading on labview about pulse width modulation and i came across duty cycle.
Can someone briefly explain what that is?

[EricH]

Originally Posted by starsROBOTICS

I was reading on labview about pulse width modulation and i came across duty cycle.
Can someone briefly explain what that is?

A quick search on "duty cycle" turned up the following recent thread: http://www.chiefdelphi.com/forums/sh...ght=duty+cycle

[starsROBOTICS]

ok now that i got that what is a standard frequency to use with the motors provided by first?

[BornaE]

Originally Posted by starsROBOTICS

ok now that i got that what is a standard frequency to use with the motors provided by first?

I don't mean to be rude but please use the search tool before posting, you have had multiple posts that can be easily found with a simple search.

and now the question, the IFI system uses 60Hz, and the new system for 2009 uses 20KHz.

Please before posting.

[Gdeaver]

If one searches on the IFI Victor web page, they state that the Fet chop rate or PWM fequency is 120 HZ. The controller must send a low for at least 8 ms before the victor can recieve the next updating 1 to 2 ms pulse. The press release for the new speed controler did state that 20 khz was the fequency for the new one. For many reasons they may find that a high fequency ia not always a good thing. The big change with the new speed controller is the powerful 32 bit microcontroller and the can buss interface. The controller is reprogramable so as the needs of First change the controller can be upgraded and it's capabilities expanded.

[Richard McClellan]

The new speed controller does output a 20kHz PWM to the motors, but that is separate from the input signal. For 2009, the input will be the standard PWM servo signal, as used with the IFI system. Once the CAN interface is opened up for use, probably in 2010, we should be able to send a signal at 20 kHz.