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* #14's address is all 0's. | * #14's address is all 0's. | ||
** Possible short under R20 | ** Possible short under R20 | ||
** Possible disconnect | |||
11 failures | 11 failures |
Revision as of 20:44, 27 July 2015
NurdNode | |
---|---|
Participants | |
Skills | Electronics, Programming |
Status | Planning |
Niche | Electronics |
Purpose | Fun |
Tool | No |
Location | |
Cost | |
Tool category |
Pinout protonode.png {{#if:No | [[Tool Owner::{{{ProjectParticipants}}} | }} {{#if:No | [[Tool Cost:: | }}
Description
The goal is to build wireless nodes that will control a bunch of LED's for cool lighting effects. The ultimate cool is to build enough, so we can put them in the connector pieces of our geodesic dome
Hardware design considerations
1 node will draw around 1A in current. For 31 nodes, this is obvisouly 31A in current at 5V, making the total power consumption 155W at full load. The current proposition is to bundle the power and signal lines into one cable, and run them in an upward spiraling fashion across each node, connecting them serially. The benefit of this setup is that it allows for easy addressing and it's simple. However, running 31A through a single power line requires a big, heavy and expensive cable.
The length of the power lines is determined at 60m. According to this site [1], at 3% acceptable loss, and using 5V at 31A the cable crossection is 16m2. A ballpark price estimate using Eijlander as supplier is roughly 330 euro.
An alternative would be to devide the power distribution into several groups. The upside is that we can get away with thinner cables, but we may require longer cables.
Yet another alternative is to raise the voltage of the grid to 12+V. This means we may use thinner power lines and still use the serial wiring setup. However, each node will have to be equipped with a switching power source to keep power dissipation at its lowest. This circuit will come at an extra cost, and having 31 nodes, this could escalate quickly.
(Why not elevate voltage a lot more, say 48V? Would reduce the current by an order of magnitude without adding more parts. Talloak (talk) 00:44, 4 May 2015 (CEST) )
Pinout of prototype
To connect the LED, hook up the wires to the corresponding channels. The + of the LED can be hooked up to either of the three + s. The design is a bit wonky, so that's why you get 3 + pins whereas only one is needed. The TX/RE/RX pins are used for debugging. Nothing is to be hooked up to those pins. The servo's need the lower 2x3 pins. I believe the diagram speaks for itself in this respect. Pin A and B are the DMX signal wires. Make sure all the A's are hooked up together as well as all the B's
Parts selection
IRL540 for power led stages?
TODO
Hardware
Calulate total length of cable required to connect all nodesCalculate price of power linesDesign power circuitDesign LED circuit (for optional leds)Design power stage for 3W ledSelect appropriate through-hole parts for breadboardingOrder thru-hole partsBuild thingamagic on breadboardSelect appropriate SMD parts for the final device.Select decoupling capsSelect connectorsSelect N-channel MOSFET
Design boardAssemble BOMDetermine pinout of PSUCreate pinout of prototype nodeBuild first prototypeTest first prototypeTest out smaller FET as replacement for the fat bastardsFix design mistakesFinalise designUpdate BOM- Create building instructions
Build device that will zero in the Servo'sBuild device that tests the channels of the LED separately.Assemble 35 Pro mini'sLabel 35 pcb's with numbers 1-100 AFTER they have been in the oven ;)Program 35 Pro mini's with firmware.Calibrate 35 PSU'sCut 100 heatsinksDrill 100 heatsinksSolder 35 LEDs to jumper wire in the following order +RGBTest channels of 35 LEDs- Stick 35 LEDs to heatsinks
- Glue 35 heatsink + LED combination to servo arm.
Pick and place 100 nodesSolder through hole parts to 35 nodesZero-in servo's of 35 nodes- Screw servoarm + heatsink + led to servo.
Set address of 31 nodes- Test address of 31 nodes by hooking it up to the DMX bus and try to talk to it using its address
Stick Pro-mini on 35 nodesSolder calibrated PSU on 35 nodes- Assemble 65 kits
- Provide documentation for kits
Cabling
Determine guage of power cablesDetermine which signal wires to use- Order more molex connectors
Get wires at ijlander, or order- Build cable
Total cable length based on 10M dome = 31 - 1 * 2m = 60m 1mm2 stereo cable will be used for the supply of power Fancy sensor cable is used for transport of signal
Ordering
100 pcs 3W Led100 pcs PSU100 Pro mini's200 Servos100 Lenses110 Jumper cables for soldering to LED3x solder pastePrototype StencilPrototype PCB'sEnough material for prototypesMetal framed stencil for final designFinal PCB'sMore molex connectorsEnough materials for final nodesAdhesive for LEDsExtra transmitter chips (after validation)
Software
Create some spiffy code to make the blinkenlichten go blink blink.- Design standalone mode
- Change firmware so pin 1 is used to toggle DMX and standalone mode
- Review firmware
- Fix issues
- Mark firmware as final
- Create a C&C lib that organises the nodes and takes care of the comms between the nodes and the higher level software. I'm thinking REST API for the higher level stuff and UDP multicast for the lower end. Suggestions welcome.
- Find a tool (better yet DIY) a tool that allows you to define an animation in 3D and project it on the geodome.
Testing
- #16 looks to have a blown power converter.
- #5's Green channel looks funny from that tesy
- #7's green is shorted
- #8 has a shorted green
- #15 has an addressing problem with the middle pin.
- #10 has the same addressng problem
- #10: DIP #4 is connected to 5V
- There is a short under the 3.9k resistor on dip 4 on #10
- #28 has no address at all - all 0's.
- #19's power supply just stopped working.
- #27's lowest address pin is not working.
- #17's green is shorted and red is disconnected.
- #14's address is all 0's.
- Possible short under R20
- Possible disconnect
11 failures
Website
Maybe set up nice website?
Links
- Potential 24V power supply: http://www.ebay.com/itm/321660472921
- Or 48V?: http://www.ebay.com/itm/261847060063
- Step down from 24V: http://www.ebay.com/itm/171381728637
- Leds: http://www.ebay.com/itm/191388798412
- Or: http://www.ebay.com/itm/221544924178 with added heatsinks onboard.
- Extra heatsinkery: http://www.ebay.com/itm/331286129263
- Sticky pads for connection: http://www.ebay.com/itm/121331880334
- Interesting source of servo's: http://www.giantshark.co.uk/product/167511/towerpro-sg90-9g-micro-servo - with returns in the UK. Promising!