Designed solely for the S.T.E.A.M technology challenge, Light It Up, this lamp was inspired by wondering if I could create something that would replicate swarming fireflies. Essentially its a lamp with gyroscopic moving parts intended for use inside and out (although its not waterproof so cannot be left outside).
The overall design of the lamp is based on a classic spherical screw cap bulb. I tried to make it look as good when operational as it does when not in use and seeing how night and day are fairly even in duration it was an important factor to consider during the design stage.
How it works:
The lamp has 4 rings and a central orb connected with axles and bearings through which current flows. For every ring, every opposing axel is a positive and negative input, and so eventually electricity gets to the orb in the middle by linking the rings up (or so I thought, more on that later...)
Each ring has 12 yellow flicker LEDs and the orb in the center has 48 yellow flicker LEDs. The outer ring is connected to a motor hidden in the screw cap of the bulb shape to spin the rings. There's also a motor inside the orb connected to a weight which displaces the weight in the orb to counter balance the rings alignment when spinning horizontally. The result being that the rings should be in a constant state of movement around their axes in different directions. Also hidden in the screw cap is all the circuitry for the lamp.
The lamp is triggered by an IR sensor located in the nipple of the bulb shape. There are 2 voltage ramp circuits to power the main motor and LEDs/orb motor. When triggered the outer ring will slowly build up speed and the LED's will fade on then, once the IR circuit cuts the power after an allotted time, the outer ring will slowly decrease its speed and the LED's will fade off.
The screw cap and the dome contact point of the bulb shape have both been designed with twist and lock mechanisms to enable easy access to the circuitry once the model has been fully built. This gives easy access if you need to troubleshoot something or alter the ramp times of the ramp circuits and trigger duration for the IR circuit.
Admittedly the design needs more work, currently the electrical current is having difficulty reaching the centre due to the poor connections provided by the bearings and as a result there is a steep voltage drop off. However I'm out of time for the challenge so I'm submitting it as it is. I think I've made pretty good progress for a fairly ambitious and unpredictable project and as it stands at the moment its still pretty cool.
I intend to address these issue in the coming weeks, using a slip ring to guarantee a stable connection into the largest ring and then refining the bearing and axel connections. I could also replace the resistors in the rings using larger values for the outermost larger rings and reducing the values as they go inwards reflecting the voltage drop from the bearing connections. This would allow me to run the LEDs safely at a higher voltage whilst still reaching the target voltage of 4.5V for the orb.
Powered by 12V (3A roughly), with an inbuilt DC regulator powering the LED's/orb motor at 4.5V.
Designed in Rhino. All meshes are manifold (watertight).
What it should look like fully illuminated (minus the rotation): http://youtu.be/S3ub-kNEwfA
This is a fairly complicated make with multiple parts and requiring a number of skills. You'll need a few power tools as well as more standard tools to make it. I’m still fairly new to 3D printing and consider myself a novice so apologies if anything in these instructions doesn’t quite make sense. I’ve made a selection of assembly diagrams (which can be found in the gallery) to compliment the instructions if you need to see how it all goes together. Also the photos of the inside of the orb and rings should help with understanding some of the processes too. Refer back to the diagrams if you need to know what particular part I’m talking about in the instructions as I needed to label each part to make it easier to write about.
All parts have been designed for assembly using fitting tolerances where necessary.
- Power drill with 3mm and 7mm bits.
- Rotary tool (Dremel) with cutting disks.
- Soldering iron and solder
- Wire strippers
- Wire cutters
- Tweezers (for the fiddly bits)
- A set of screwdrivers
- Multimeter (to verify electrical continuity)
- Sand paper (or equivalent)
- 12v 3A power supply
- 19 MF63ZZ Bearings (6mmOD, 3mmID, 2.5mmW)
- Brass tube (7mmOD, 6mmID)
- Brass rod (3mm diameter)
- 12V motor geared to 40rpm
- 5V motor from a PlayStation dual shock controller
- 60rpm gear box with middle of gearbox casing removed
- 12V PIR circuit with relay function
- DC-DC regulator
- 96 Yellow flicker LED’s
- 96 120ohm ¼ watt resistors
- Wire rated to 2.5-3amps (both single core and multi)
- Silver conductive epoxy
- Standard quick cure epoxy
- 72 No.2 self-tapping screws (5mm length)
- 7 No.3 self-tapping screws (6mm length)
- 2 M4 screws (10mm length)
- 4 M4 rubber washers
- 2 mm thick rubber sheet
- Shrink tube
Components required for the voltage ramp circuits:
- 2 45x45mm prototyping PCBs
- 2 12v SPDP relays
- 2 555
- 2 LM393
- 2 2N222A
- 2 2N4403
- 2 BS170
- 2 1000uF electrolytic capacitors
- 2 220uf electrolytic capacitors
- 6 0.1uf disc capacitors
- 100Kohm trimmer
- 6 1Kohm resistors
- 2 4.7Kohm resistors
- 2 2.7Kohm resistors
- 2 10ohm resistors
(The above list of components is for 2 of the ramp circuits hence why there are 2 lots of many of them.)
I’ve never understood the inclusion of these in instructions since every printer and every filament will differ slightly and no one knows what settings are best for you printer than you yourself.
Anyway I have a fairly budget Chinese generic printer (based on a reprap Prusia i3) and printed the parts using 1.75mm white PLA and transparent PLA filament. I printed the white at 200C and found the transparent needed to be slightly hotter at 205C.
I used Simplify3D as my slicing software using a 0.4mm nozzle and setting the extrusion width to 0.5mm since a lot of the measurements in the design are multiples of this (I like round numbers).
I printed at a resolution of 0.2mm and oriented the parts depending on which would require less support material.
I set the infill at 20% but this could probably have been lower. For the support infill I used 20% with a horizontal gap of 0.3mm and an infill angle of 45, -45 degrees.
Cut 48 of the LED leads down to 3mm and one end of 48 120ohm resistors down to 5mm (these are for the rings). Solder the positive lead of the LED to the shorter lead of the resistor.
Cut 2 pieces of brass tube to 5mm, 2 pieces to 6mm and 15 pieces to 8mm and clean any burring that may be on the outside/inside of the tube.
Cut 1 piece of brass rod to 25mm, 1 piece to 30mm, 2 pieces to 20mm and 6 pieces to 22mm. Taper the ends so they’ll pass through the bearings easier.
Print all of the parts and remove support material where necessary. Some of the parts are 1 wall, 1mm thick and so can be fragile while removing supports (e.g. the ring covers). The best way I found for removing these supports is to place the part vertically and chip away at the support material with a small flat head screw driver. This way you’ll put less pressure on the actual part and it will be less inclined to break.
Drill out the LED holes in the orb and ring parts with a 3mm bit and the larger holes where the brass tube will be inserted with a 7mm bit. This just ensures a tight fit.
Insert the 2 6mm lengths of brass tube into each side of the orb. You’ll have to put some pressure on it to get it to go in. Each side of the orb has opposite entry points for positive and negative so when you lay the wire in the channels one will have to connect to each separate brass tube (see the pic).
Solder small clasps onto 2 of the wire and pass through the clasp holders on one half of the orb, place along the wire channels and once you reach the end snip one just short of the brass tube and bend the other to connect to it. On the other half pass the other 2 wires through the contact holder and lay along the wire channels however this time making sure the opposite wire connects to the brass tube, so when the orb half’s come together you get continuity throughout for positive and negative. Leave about 3mm of wire protruding from the contact holder which will fit into the contact clips of the other half of the orb. You may need to use some shrink tubing on the wire to get it to fit snuggly between the walls of the channel. Make sure there’s exposed wire at every gap in the channel walls for LED/resistor connections.
I designed resistor clips into the orb design to give the motor room to rotate freely and to avoid risk of collisions. Insert the LEDS into the holes and clip the resistors into the clip next to it. Bend the positive lead of the LED and one lead of the resistor together and snip any excess. Choose which wire channel will be positive and negative and bend the correct leads to the correct wires. Snip off any excess wire. Once this has been done for the whole orb use the silver conductive adhesive to ensure good electrical contact on all connections (including the 2 for the brass tubes). Once this has cured (and you’ve verified continuity throughout the connections) you can go over the contacts with a standard epoxy glue to give added strength.
Solder 2 clasps to 2 small lengths of the wire for the motor connections and pass through the clasp holder, connect one to the positive wire and the other to a negative wire previously laid in the orb.
Solder 2 4mm sections of single core to the ends of the wires of the small motor to be used in the orb. Screw the orb motor casing into the relevant half of the orb and pass the motors lead ends through the small holes that align with the clasps underneath.
Fill the orb motor weight with something weighty (I used leaded solder balls) and seal the fill hole with glue. Push the motor weight onto the motor shaft.
Insert 4 of the 8mm brass tube sections into each ring. Place 2 lengths of wire inside the circumference of the rings, one either side of the cover screw holes. Bend into the curved channels at each axel point. Each wire will need to connect to 2 of the 4 brass tubes at 90 degrees to each other, so every tube opposite each other will be positive or negative. Place the pre soldered LED and resistors into the LED holes, bend the resistors back on themselves so they’re in line with the LED and connect the other lead of the resistor to the innermost wire. Connect the negative lead of the LED to the other wire. Use silver conductive epoxy to ensure good connections throughout. Once cured go over with standard epoxy to give added strength.
Insert bearing blocks into the ends of the brass tubes which will connect to the next ring inwards, and on the opposite end of the other 2 tubes for the axels that will connect outwards. You’ll want a tight fit so a fair amount of pressure is required to get them in. Using the 22mm lengths of brass rod, place axel ends onto one end of them. Coat the insides of the brass tube with silver conductive epoxy and insert a bearing then coat the inside of the bearing too. Insert the brass rods through the bearing of one ring and into the next. Place an axel end onto the end of the brass rod to secure it in position. Do this for all the rings, alternating at 180 degrees for each new ring. Important: pay attention to which connections you’re connecting up, you want to be connecting positive and negative channels as defined by the way you connected up the LEDs (innermost wire positive, outer negative). For the orb it’s a similar technique but using the 20mm lengths of brass rod instead. For the orb insert a bearing block into the outside of the brass tube on each side, coat the inside of the tube with silver conductive adhesive and insert a bearing. Then place a bearing block onto the 20mm lengths of brass rod and pass through from inside out to the smallest ring. You can then put the two half’s of the orb together using a few dabs of glue to hold them together. Make sure the contact points of the two half’s make good contact when putting them together. Check continuity from the contact points at each end of the orb.
The largest ring that connects to the motor shaft connecter has a 3mm hole instead of the usual 7mm holes for the brass tubes. Here you need to insert the 30mm section of brass rod, first drill it out to make sure you have a clean hole then insert the rod. It’ll be a tight fit so you’ll need to apply a fair amount of pressure to get it in. Attach the wire on the inside of the ring as you would have for the brass tubes using silver conductive epoxy. Place the covers on the rings and screw down.
Connect the outer supports of the bulb shape onto the inside of the screw cap base There are 3 different types, Solid, solid with a slot in the top and hollow. You’ll need 3 solid ones and 1 with a slot which will need to go over the tab slot for the main screw cap to give it clearance. You’ll need the hollow supports to thread wires through for the IR sensor, I put these opposite each other but there’s no set rule for where they should go. They should snap on nicely and secured with a screw. Next attach them to the nipple casing, again screwing them down to secure them.
Thread through 4 wires from the top of the screw cap base, through the hollow outer supports, down to the nipple casing. 1 wire is the negative for the largest ring and the other 3 are for the IR sensor. Screw on the covers for the hollow outer supports.
Desolder the IR sensor from the PCB it’s soldered too (saving precious millimetres), take note of which pin is attached to which coloured wire for when you connect it back up. Solder 3 of the wires to each pin on the IR sensor.
Drill through the IR sensor/bearing holder with a 7mm drill bit, insert a 5mm section of brass tube. Coat the inside with silver conductive epoxy and insert a bearing. Screw onto the underside of the nipple cover. Take the remaining wire and bend it into the gap so it connects up against the brass tube. Use some more silver conductive epoxy to make good contact. Fit the IR sensor into the bottom of the holder, it’ll be a snug fit but you shouldn’t have to force it. Put the nipple cover on the nipple casing and screw down.
Take the motor casing and line the inside with the 2mm thick rubber sheet. This’ll help reduce the motor vibration reverberating throughout the printed parts. Place 2 M4 rubber washers into the inside base of the motor casing over the holes and insert the motor so the securing holes on the motor gearbox match up with the ones on the casing. Take another 2 rubber washers and place them onto 2 M4 screws and screw through the casing into the motor to secure it in position. Pass through the large hole in the screw cap base and align the screw holes. Screw down to secure.
Place the motor shaft connector onto the shaft of the motor. Drill through the top bearing holder with a 7mm drill bit, insert a 5mm section of brass tube. Place into the inside base of the motor end/outer support cover. It’ll be a snug fit and may need some pressure or a few taps to get it in. Coat the inside of the brass tube with silver conductive epoxy and insert a bearing. Attach the motor end/outer support cover to the screw cap base, negotiating all the out supports into their correct openings. Secure with screws from the other side.
Take the orb/rings assembly add pass through one of the gaps in the outer supports, you’ll need to align the rings to get it through. It should be oriented so the protruding axel, which will connect to the motor shaft connecter, be facing upwards. Guide the axel into the hole in the motor end/outer support cover and push upwards so that it’s inserted into the motor shaft connector.
Take the last remaining section of brass rod and attach an axel end onto one side. Coat the inside of the brass tube at the bottom of the ring (opposite the axel you just inserted into the motor shaft connector) and insert a bearing. Underneath the large ring slide under the large ring support and centre it and then insert the axel.
Solder wire onto the 4 connections for the DC-DC regulator and screw on to secure. Take the largest of the circuit supports and screw down onto the motor casing. Screw the first ramp circuit onto the 4 screw holes in the circuit support. Wire up as per the wiring diagram, you’ll want to do this before adding the next tier of circuitry as you need access to the contact terminal screws. Screw the remaining 2 circuit supports onto the second ramp circuit placing them on the top of the circuit PCB and screwing down from the underside then screw onto the pillars either side of the first ramp circuit. Wire up as per the wiring diagram. Finally screw on the PIR circuit upside down onto the remaining 2 small circuit support pillars.
Feed the main wire flex through the top of the screw cap and secure it by screwing down the flex bracket and connect up the positive and negative wires. Place the main screw cap section onto the screw cap base passing the tab through the slot and twist to secure it. Screw to secure it from the hole on the outside of the screw cap base. In the same way place on the screw cap top onto the screw cap main section and twist to secure, screwing in from the outside to secure.
Send me a message if you don’t understand anything, I’ll be happy to help.