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17. Machine design

Tasks

Group assignment

  • Design a machine that includes mechanism+actuation+automation.
  • Build the mechanical parts and operate it manually.
  • Document the group project.

Details of the group assignment are in the group page.

Programming Environment

Installation of the pygestalt module in the virtual environment.
Installation of the pyserial module in the virtual environment.

Testing

I connected the single node with 12V power supply and used the single_node.py example. I just had to change the portName at the def initInterfaces(self) of the virtualmachine with my COM port number which was COM4.

def initInterfaces(self):
    if self.providedInterface: self.fabnet = self.providedInterface     #providedInterface is defined in the virtualMachine class.
    else: self.fabnet = interfaces.gestaltInterface('FABNET', interfaces.serialInterface(baudRate = 115200, interfaceType = 'ftdi', portName = 'COM4'))

Testing the installation by moving a single node.

References

USB-RS485-WE Cable Signal Descriptions (taken from the datasheet)
Color Name Type Description
Black GND GND Device ground supply pin.
Brown Terminator 1 Input Pin 1 of 120R Terminating Resistor. Only Required if the USB-RS485-WE cable is the first or last device in a multi-drop RS485 System, to meet RS485 Termination Requirements.
Red POWER Output Default output is +5V when active, 0V during suspend. Power output can be customized to 0V, if required, contact FTDI Sales Team ([email protected]). Switchable power to external device, 250mA max. OFF during suspend
Orange Data+(A) Bi-Direction Data + (A) Signal
Yellow Data-(B) Bi-Direction Data - (B) Signal
Green Terminator 2 Input Pin 2 of 120R Terminating Resistor. Only Required if the USB-RS485-WE cable is the first or last device in a multi-drop RS485 System, to meet RS485 Termination Requirements.

Ilan’s Master Thesis

Gestalt Tutorial

Physical layer is called Fabnet, which is a multi-drop network, i.e., multiple nodes share a single set of communication wires. Signaling is differential and is based on the RS-485 specification. A bridge between the FTDI cable and the gestalt node is required.

Problems

  • installing gestalt module from imoyer didn’t work properly. I was not able to import the module, so I used nadya’s version.
  • It can run only on python 2.7 versions
  • After finishing the desired movement, the motor is not getting turned OFF i.e., it is still taking current and stuck which causes the getstalt board to heat up a lot.