Synchonizing Four ESCs At Once

 (note: this one has been sitting in the edit queue for quite a while.  Long time readers will notice with amazement the Arcticopter I.)

When setting up a new quad, it's important to set the endpoints on each of the ESCs.  Here's an easy way to do them all at once.

Grab a breadboard and five 3-way male pins.  Four of these will be for the ESCs, and one of them will be for the throttle channel of the receiver.

Put the pins in the breadboard like this.  This will allow all ESCs to be controlled at the same time by the receiver.

Hook up all the ESCs and the receiver.  Make sure all the connections have the same orientation.








Now follow the endpoint syncronization procedure for your ESCs. Almost all of them are similar to the procedure in section VII of this manual.

• remove any props if the ESC are in an airframe
• power up radio
• move throttle to max
• power up ESCs
• the ESCs will make their initial sound, then go into a continuous beep mode
• move the throttle to min
• the ESCs will make the final beep
• All ESC endpoints are now calibrated and consistent with each other.

blogodex = {"idx":"ESC"};

Interesting 4x20A ESC

Here's an interesting ESC from HobbyWing.  I'd like to find somebody that's had some experience with one.  Claims PWM up to 432 Hz.  Not bad for $33?

RCTimer ESC's easily flashable

There's a nice RCGroups post showing that the RCTimer ESCs are easily flashable, withe the pads conveniently aligned on the edge of the unit.  They use tgy.hex.

Notes on reflashing ESC firmware

A couple of random notes about this.  The firmware mentioned is good for multicopters as it supports a very high update rate.  The code is fast, can support a prop speed of 120,000 RMP... yikes!  On the thread, someone notes "Finally that annoying 8kHz whine from the motors is gone, and motors are very smooth."

• Nice rcgroups HOWTO by Nek.
• Protostack AVR programmer.  cannot use FTDI programmer.
• Using an arduino as an AVR programmer.
• Cheap one on ebay.
• github tgy project. AVR ASM, baby!

ESC with data recording capability

Phoenix Ice from Castle Creations.

Data Logging
Ice brings another incredibly useful feature, extensive data logging capabilities. The controllers are able to measure and record many parameters at sample rates that you choose between 10 samples per second and 1 sample per second. Data points include:

• Battery Voltage
• Battery Ripple
• Battery Current
• Controller Temperature
• Controller Input Throttle
• Controller Motor Power Output
• Motor RPM

This data is stored directly in the controller and may be accessed once the run is over using the Castle Link USB adapter (sold separately) and Castle Link software (available free at castlecreations.com). The Max Log Size is 21,504 bytes, everything takes one byte except for motor rpm which takes two.

• Logging 'Battery Current' at only a 1 sample / second - 358 minutes of logging time (almost 6 hrs)
• Logging 'Motor RPM' at only 1 sample / second - 179 minutes of logging time
• Logging everything at only 1 sample / second - 44 minutes of logging time
• Logging everything at 10 samples / second - 4 minutes and 28 seconds

By The Numbers: ESC

The ESC (electronic speed controller) is used to control  the speed of a brushless motor.  It usually has a BEC ("battery elimination circuit") to provide power to servos and the other receiver outputs.

• Continuous Current -- how much current can pass through the ESC on a sustained basis.
• Burst Current -- how much current can pass through the ESC for a short "burst" of time (usually 60 seconds).  If you exceed this time, you will probably burn up the ESC.
• BEC (battery elimination circuit) -- How much power is available to the servo and other receiver outputs.
• Cells-- the voltage and type of battery supported.
• Weight: QED
• Size: QED

Wiring:

• two input wires from  the battery
• three output wires to the motor
• three-wire bundle to the receiver.  two wires power the receiver (including passing power to the receiver outputs), one wire is the control wire receiving the throttle control signal.

ESC Programmer: some ESCs can be programmed.  This can be done via the receiver (by "clicking"  through entries using the joystick) or more easily with an ESC programming card ("no more black magic throttle stick controls!").  Typical  programmable values are:

• brake -- on/off.  stops the motor immediately when throttle is cut, used for feathering props.
• battery type -- battery voltage, or "auto".
• cutoff type -- gradually reduce or immediately shut off power when the voltage threshold is reached.
• cutoff voltage -- 2.6V, 2.85V, or 3.1V per cell.
• start mode -- normal, soft, very soft.  helis use soft, planes use normal.
• timing mode -- low, medium, high.
• music -- for some inexplicable reason, you can program the esc to play different songs at startup.