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FOC_Openloop terminal command via CAN?

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Jackl
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FOC_Openloop terminal command via CAN?

Hi all,

for my application I need to apply a rotating field to my machine at high currents. Basically exactly what the terminal command foc_openloop does.

Is there any way to control this via the CAN Bus? I am sure you can activate it via can, because it also works if the VESC is connected to VESC Tool via another Vesc over can but I am struggling to understand how the much more complex can forwarding seems to work.

With normal CAN Commands (https://github.com/vedderb/bldc/blob/master/documentation/comm_can.md) it seems like it is not possible.

Does anyone know more or could point me in the right direction?

Thanks;
Jakob

vadicus
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Yeah, it will work. You just need to mod your firmware a bit. 

This would be a good example to start with (from here: https://github.com/vedderb/bldc/blob/c9dbe942e0262473ae7e978137e1f2c9928...

    case CAN_PACKET_SET_CURRENT:
            ind = 0;
            if (len >= 6) {
                mc_interface_set_current_off_delay(buffer_get_float16(data8, 1e3, &ind));
            }

            mc_interface_set_current(buffer_get_float32(data8, 1e3, &ind));

            timeout_reset();
            break;

You might simply replace the above mc_interface command with mcpwm_foc_set_openloop_current(current, DIR_MULT * rpm) to maintain the standard command structure, provided you will never need to use regular FOC/non-openloop current set command.

 

 

 

 

 

NextGen FOC High voltage 144v/34s, 30kw (https://vesc-project.com/node/1477)

Jackl
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Thanks,

that sounds like a great insight and a good tip :-)

Jakob