13. Applications and implications¶
Assignment: Propose a final project that integrates the range of units covered.
Learning outcomes: Define the scope of a project, develop a project implementation plan to reach targets & objectives.
Questions answered?¶
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[x] what will it do?
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[x] who has done what beforehand?
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[x] what materials and components will be required?
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[x] where will they come from?
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[x] how much will it cost?
The Final Project¶
As final project i will create a revolving head for Pick & Place of SMD components for Electronics production.
Target here is to create a simple Fabbable revolver head that runs semi-autonomous via Wifi connection.
If project timing allows i will add optical assistance for more accurate placement So i will include 1 small size camera on the chassis and one on the caddy connected to a Respberry Pi zero for OpenCV processing and serve as a feedback for the hosting XYZ motion system. This feedback could potentially feed a Kalmann Filter to improve speed and positional accuracy of the system.
Who’s done what already?¶
Market¶
There are already many smaller units available for sale but most of them have only a single pick nozzle requiring them to travel a lot between pickup zone and workpiece.
More advanced/expensive devices use multiple heads, revolver heads or a chain of heads.
The OpenPNP group has done a lot on the software side of things
Me¶
In the previous week on output devices i already build a stepper motor controller capable of both step/dir and sequence stepping.
In sensing week i included end-stopper & proximity sensing allowing each stepper controller to
also relay end-stop status/proximity inline with controlling steppers.
In design week i started Parametric design for the assembly of the PnP unit.
Process & Tasks¶
What needs to be made?¶
Main focus of the project is to create the Rotating PnP head with some level of autonomy.
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Rotating head incl Pick & Release valve \
- 3D printed body based on a planet gear design, brackets for motors \
- Integrated vacuum pump (tube) \
- Pickup nozzle holders with load and release action and a limited nozzle rotation (?? degrees)
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Motion system (Openrail inspired) \
- fittings & brackets for idler pulleys, steppers, caddy
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Electronics \
- Motor controllers, integrated end-stop detection with WIFI access/control
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Vision system (optional) \
- Camera holder brackets
what tasks need to be completed?¶
- CNC-ing all chassis parts
- XYZ system has to be assembled & tested (will start in Machine building week)
- Rotating head elements need to be produced, assembled and tested mechanically
- Peristaltic pump has to be tested for functionality & pressure (if not working properly we will switch to an external vacuum pump)
- Stepper controllers have to be completed & tested (XYZ system + Rotator)
Open questions yet to be answered / Researched¶
- Syncing of autonomous wirelessly controlled NC actuators/sensors
- Vacuum pressures with on-board using a built in peristaltic suction pump vs required pressures for component
- Is a pressure reservoir required for the setup? Maybe not but we should factor it into the 3D designs for the head.
- Am i allowed to use the OpenPNP platform as basis for our control? (are we allowed to do this)
Bill of Materials¶
c) what materials and components will be required?
d) where will they come from?
e) how much will it cost?
The answers to the questions above will allow you to create your BOM, or Bill Of Materials.
Schedue & Evaluation¶
Schedule to success¶
- [ ] Wk15 - Communication using ESP32 & Serial as backup
- [ ] Wk 16 - Build linear rails (XYZ system)
- [ ] Wk 17 - Final pcb design & production integrated sensor/actuator/wifi node
- [ ] Wk 19 - Build the PnP head and test
- [ ] Wk 20 - Stitching it all together, NC software to control
Evaluation of success¶
As a proof of concept the machine should be able to travel to a designated pickup zone, pickup at least 2 SMD components, travel to designated position on the work piece and drop off those components.
Initially purely coordinate based but if we manage to get time to add the vision to the system we could also target positional adjustments based on optical pattern recognition.