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Unread 04-01-2010, 18:39
EricVanWyk EricVanWyk is offline
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Re: CAN control weirdness

Quote:
Originally Posted by nathanww View Post
The documentation talks about a "voltage control mode", where the voltage is varied according to the CAN command. Does this mean that the Jaguar in this mode is just sending an analog voltage instead of a PWM wave?
No, it is still a duty cycle modulated wave form. The difference is that it will compensate to ensure a fixed voltage across the motor. Without this feature, drive strength is dependant on battery voltage and load. With voltage mode, some of this variability is compensated for by dynamically changing the duty cycle.

It is not capable of creating an analog voltage.

Quote:
Originally Posted by nathanww View Post
As I understand it, CAN will be run by daisy-chaining Jaguars together, with an additional safety verification provided in the form of a "heartbeat" PWM from the digital sidecar. However, if a point on the daisy chain fails, will the "downstream" Jaguars continue executing the last recieved command?(since there are no further commands coming through the CANbus and the heartbeat is telling it that everything is fine). Or is there some sort of additional safety system that will detect the loss of connection and shut down?
Without going into too much detail, this is not a problem. A Jaguar that is not receiving fresh CAN messages will shut down, even if the PWM heartbeat tells it to continue.