MTB routes
Sheepstor to Red Lake loop
e-Bike Lithium Ion Load Tester
Using power resistors is not feasable, but AC halogen bulbs are easily sources up to 500W , so multiple bulbs can be used to vary the current 120 Vrms 500 bulb watts 28.8 bulb resistance 52 battery voltage 93.88889 watts 1.805556 amps So on a 52V battery pack a 500w halogen bulb would draw about 1.8Amps Voltage can be monitored with a simple voltage divider to lower the 52V to something suitable ( < 3v probably ) Current can be…
HAProxy – Slowing down abuse with user friendly rate controls
There are various situations where clients can overload a website server, but you don’t want to return a 4xx or 5xx simply because the system is getting bogged down, instead it would be better to have a mechanism which tries to take the pressure off the backend server to give all clients a fair chance. Thankfully HAProxy has a couple of ways that requests can be slowed down on their way to the backend, the cleanest mechanism is to use…
UAV parachute recovery system
In the event that something goes horribly wrong while at high altitude it makes sense that things come back down under a bit of control! droneyard.com/2013/07/01/uav-parachute-recovery-system/ What i’m struggling to solve is how to design the deployment system so that it does not tangle around the props when the UAV is falling in a tumble. I’m currently imagining a tub with either spring loaded deployment mechanism or a ballistic launch system.
Circular Wireless 5.8GHz Helical Antenna
A great antenna for long range FPV with the same circular polarisation as the clover leaf and skew antennas www.circular-wireless.com/en/products-page/helical-modo-axial/heliaxial58/ Available in the UK from quadcopters.co.uk/circular-wireless-58ghz-heliaxial-fpv-antenna-532-p.asp
UAV Gimbals
A brushless motor gimbal is the only way to really get a smooth filming platform www.goodluckbuy.com/aluminum-brushless-camera-mount-gimbal-kit-w-motors-and-gimbal-controller-for-compact-camera-aerial-photography.html www.unmannedtechshop.co.uk/2-axis-brushless-gimbal-controller.html desirerc.co.uk/index.php?option=com_jcommerce&pgn=product_info&products_id=105 www.rctimer.com/product_950.html
Programmable LED strips
These are perfect for so many cool applications. I really want to upgrade the static red and white LED strips on my Quadcopter with these so that the whole strips and function as a white strobe as well as navaigation lights and also to show warning events, like low battery etc. 32 LEDs per meter – www.adafruit.com/products/306 60 LEDs per meter – www.adafruit.com/products/1461 Arduino code library – github.com/adafruit/Adafruit_NeoPixel It is a shame that the newer 60 LEDs per meter…