Single or multi cell LED driver solution 800mA current
SINGLE OR MULTI CELL LED DRIVER SOLUTION 800mA current
Up to 1.5 A Constant Current
Switching Regulator for LEDs
Up to 1.5 A Constant
Current Switching
Regulator for LEDs with
ON/OFF Function
LOW-POWER DC/DC BOOST CONVERTER (250mA and 400mA versions)
Single Cell LED Driver, Variable Current (max 350mA)
Excellent read on one man’s journey through 6 years of experimentation with making plastic parts:
Local supply store for casting materials
http://forum.allaboutcircuits.com/
So adding a capacitor and resistor in series, adds a delay.
So for a 0 .1 sec delay, I need a 100μF capacitor and a 1kΩ resistor.
For a 0.5 sec delay, I need a 100μF Capacitor and a 5kΩ resistor.
Some points of interest:
– I did some tests on using a belt 450 tail assembly, and with a bit of modification (adding some idler pulleys to keep the belt from skipping) I achieved just over 1kg of thrust (before belt started skipping) – (my research) and my design of idler pulleys
– I’ve also tried putting a motor directly at the prop shaft, (to eliminate the power transmission through the boom) (my research). The problem I’ve found with putting a motor directly on the shaft is that you can’t get a motor with the proper kv to spin large 200mm blades. Gearing is almost always the best way to get the speed of a motor (at it’s peak efficiency) to a speed those blades can hanle.
– If you’re not looking for inverted flight, I’ve found these heavily cambered blades to produce much more thrust then the symetric 250 sized heli blades. (My research) and still maintain pretty good efficiency. (some photos of my test setup)
– To size your main motor, here’s some numbers I came up with from my test rig. To produce 1.57kg of thrust with the blades mentioned abode, I was sucking back 200W. (my research) For a spreadsheet of thrust numbers (and power required to achieve it) see a spreadsheet I put together. Again, more info to help you size the main motor. (spreadsheet link) Make sure you account for 15-20% losses in drivetrain.
– Another spreadsheet I used to calculate thrust and power (and many more things) (spreadsheet link). Al ot of my initial estimations were done with this. The results of this spreadsheet are not far off from actual tests I did. I’d way within 10-15%.
Process to get PCB boards made.
– Design in Eagle, and export from the CAM module in Eagle layers 16, 17, 18, 20, as GERBER_RS274X
– Also export layers 44 and 45 as EXCELLON
– Import gerber file and excellon fine in CircuitCam
– Isolate as required (using only small and standard tools), and batch export DXF ;this outputs 4 files (small tool path DXF, Standard tool path DXF, Drill DXF and border DXF)
– Import DXF files in CNC USB Controller software, and export “Toolpath to G-code”
– Each DXF file will have a .nc file to be cut with the appropriate tool.
Places to get End Mills and drills especially really small bits.
http://www.traverscanada.com/
http://www.precisebits.com