Unofficial SK720 Resource, FAQ, & Compass 6HV Data. CC Phx ICE 100 SK720 (pg #72)

[georgi UK]

=] please post this on the main page, attention assured!

georgi UK

[Silverexpress01]

Originally Posted by Silverexpress01

Hello,

In using simulators all Winter here are some Real Flight variant models I conjured up. Real Flight has AFS (automatic flight stabilization) gyros that behave similarly to the accelerometers in the SK-720.

See the description in the model for the list of parameters.

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There are currently two files attached:

1. Dominion 3D 90 - FBL_Beginners_v3-3_AV.zip
Version 3-3:
- Normal mode is setup with low rates and Expo. Great for hovering and orientation practice.
-Swapped out Ch.5 2 pos switch from Tail Gyro control to Self Leveling Upright control
-Ch.5 switch now allows you to turn on and off Self Leveling with a flip of a switch. Allows you to use the SL as a bailout when gain is set high.
- 2 Pos. Channel 5 Up=Self Leveling Upright ON
Dn= Self Leveling Upright OFF
- Ch.6 Knob adjusts the Self Leveling gain on the fly.
(Hi)100<=Left Right=>0(off)
-Expo and lower rates on Heli when in Normal and Stunt mode 1.

-V3.3 Fixes the Knob function. Was not working. Also cleaned up the Software Radio channels in the Edit model menu.
-This is the last and final version update (Yes, I'm a perfectionist). If there are any other issues, please PM me.
-If you'd like to change the Expos, and Rates, just go to the channel in the Software Radio section of the models editor, and change the values there. You should only be concerned with three channels...

Channel 1 = aileron
Channel 2 = elevator
Channel 4 = rudder

I've also re-labeled the throttle and pitch curves under channel 3 and channel 6 respectively. Feel free to change the points to suit your flying style. If there are not enough points, use the "resample" box to add more. Goodluck! Oh, and there is more to come.....

-Setup with ch.6 Knob not supported by SK-720

2. Dominion 3D 90 - FBL_Inverted Trainer_v3-2_AV.zip
Version 3-2:
- Normal mode is setup with low rates and Expo. Great for hovering and orientation practice.
-Swapped out Ch.5 2 pos switch from Tail Gyro control to Self Leveling Inverted control
-Ch.5 switch now allows you to turn on and off Self Leveling with a flip of a switch.
- 2 Pos. Channel 5 Up=Self Leveling Inverted ON
Dn= Self Leveling Inverted OFF
- Ch.6 Knob adjusts the Self Leveling gain on the fly.
(Hi)100<=Left Right=>0(off)
-Expo on tail in all modes, and low Dual Rates when in Normal and Stunt mode 1.

-Inverted Self Leveling not in SK-720. This is a "what if" scenerio

3. FBL_MD500E_v1-1_AV.zip
Version 1-1:
- Added cyclic gyros to simulate a Flybarless controller
-Now has no more tendency to pitch upwards in FF.
-Also has Upright Self Leveling via Ch.5
Ch.5 Self Leveling: UP = ON; Down = OFF
-Channel 6 Knob controls the gain of the Self Leveling.
-Had to increase overall Pitch range of Collective and Cyclic to accomodate the Gyro's range of compensation. Because of this you can invert this heli (I know it's not scale, but it's how the algorithms in the Gyros require minimum deg of pitch).
-Make sure you compare this to the Real Flight non-FBL version to feel the difference in flight control dynamics.
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I tried to match the SK-720 advance options (parameters) to the list of gyro adjustments in Real Flight. Here is what I came up with so far:

Real Flight.................................................. .......SK-720
Rotation Rate (Deg/Sec).................................Control Rates (Deg/Sec)
Rotational Acceleration (Deg/Sec^2).................. Bell Gains (Deg/Sec^2)
Heading Hold Gain........................................... Hiller Gain
Rate Gain.............................................. ......... Damping Gain
AFS Gyro Master Gain.................................. Self Leveling
Heading Hold Mix.......................................... Hiller Decay?

The values are not 1 to 1, but the functions appear to work similarly.

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A video of Self-Leveling as a bailout in action from Skint Eastwood, and in this instance it is being used to turn the heli upright:

http://www.youtube.com/watch?v=uNq0V4_r0oU

This is an update to my description above:

An upcoming SK-720 firmware update will include Inverted Self Leveling! Whoo-hoo!

See info here for now: http://www.helifreak.com/showthread.php?t=296311

[Silverexpress01]

A neat tutorial on the implementation of accelerometers and gyros (for the hobbyist).

http://www.instructables.com/id/Acce...Gyro-Tutorial/

[Castel]

Compass 6HV users with SK-720:

Boltor ( latest setup )
- SK-720 with Power Bus, using governor
- HW Platinum 70A ESC
- Hyperion Phase Sensor (for gov)
- DS610 Cyclics, DS650 Tail
- Edge 95mm CF tail blades
- Western Robotics Hercules Super BEC
- Futaba 8FG, with s-bus (using R6203SB FASST Rx) into the SK720

Heathy
- SK-720 with powerbus, v 3.02
- Hobbywing 70A ESC
- Hyperion Atlas DS20x-SMD Cyclics, DS20x-GCD Tail
- Stock dampers
- KBDD Extreme edition 96mm tail blades
- Western Robotics Hercules Super BEC

J0hnny007
- SK-720 with powerbus, v 3.0
- CC ICE 80 HV
- JR 8917 HV Cyclics, BLS251 Tail
- KBDD Dampeners
- KBDD Extreme edition 96mm tail blades
- Western Robotics Hercules Super BEC
- Western Robotics Titan Dual Step-Down Voltage Regulator

Colonny5
- SK-720 with powerbus, v 3.0
- Hobbywing 70A ESC
- Hyperion Atlas DS20x-SMD Cyclics, DS20x-GCD Tail
- Stock dampers
- Stock tail blades
- CC BEC Pro

Johnjonfenomenon
- SK-720 with powerbus, v 3.01
- Hobbywing 70A ESC
- Align DS610 Cyclics, DS620 Tail
- Edge 623 FBL blades
- KBDD lime dampers
- KBDD Extreme edition 96mm tail blades
- Western Robotics Hercules Super BEC

Andy.Kim
- SK-720 with powerbus, v 3.02
- CC ICE 80HV
- Stock Motor + 11T (Governed at 2300HS)
- JR 8917HV @ 8V Cyclics, BLS251 @ 4.8v (WR Step Down) Tail
- KBDD Lime Green Dampener
- Radix 92mm Tail Blade

Castel
- SK-720 with powerbus, v 3.02
- Hobbywing 70A ESC, SK-720 Governed
- JR 8917HV Cyclics, Outrage BL 9188HV Tail servos
- KBDD Lime Green dampers
- KBDD tail blades
- Western Robotics Hercules Super BEC

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TIPS / ISSUES RESOLVED for reference

TAIL
Advice for optimal tail setup
- (Heathy, KBDD 96mm tail blades, DS20x-GCD Tail servo) Ball at 15mm on tail servo horn and on the inner hole in the tail pitch slider arm. Adjust tail servo travel end points to around 120% on both sides, you will have to remove the tail slider silver spacer on the tail box side. A good starting TX gain is 40%, tail is now rock solid!

Bouncing on stops
- (Castel, KBDD tail blades, Outrage BL9188HV tail servo) Changed to inner tail pitch arm hole and 15mm servo horn distance from center, no binding anywhere! I set tail pitch at 0* for mid stick and servo travels around 110% on both sides. Headspeed 1850rpm minimum. This fixed bouncing on stops.

SK GOVERNOR
Pulsing/oscillating throttle with SK governor
- (Castel, stock HW ESC, 18.75 motor timing, hyperion sensor) 35% of governor gain is the suggested value to start for using the SK's governor function tuning. Throttle will pulse/oscillate if gain is either too high or too low, it did for me at 15% and at 60%. Trick is reduce gain little by little (1-2%) at a time to find the sweet spot. With stock HW ESC and 18.75 timing it end up being 26% for me, steady RPMs for 1850-2200.

Wobbling on spool up with SK Governor
- (Castel, Stock HW ESC w/ stock firmware, KBDD Lime Green dampers) The stock ESC does not have a very good soft start. Even though tight, the blades can shift a little on start creating a lot of wobbling during spoolup at low rpms, this goes away as soon as the speed keeps raising. With the default 100% Low Ramp setting for the SK-720 governor the wobble is way more than ideal. You can raise the ramp to 140% to get past this wobbling or the best choice is to update the HW-ESC firmware with the Turnigy version which has an improved soft-start and leave default 100% low ramp.

[zorax2]

This is a clarification for mounting the TM1000 with the SK720 to allow it to bind:

RED is the positive power lead and the BROWN is the Negative. The ORANGE is the signal line.


To provide power and allow the TM1000 to be able to bind, you must cut the orange cable between the SK720 and TM1000 so the TM1000 gets just the positive and negative feeds.


Plug the connector into the SK720 with the orange lead cut into one of the open slots (I used IO-C) and you will now be able to bind the TM1000 along with your regular receiver to your transmitter. I did this to be able to monitor the voltage levels in my Trex 450 Pro.


I'll post this in a couple relevant threads as I wasn't able to find comprehensive instructions (for a newbie) to guide me through this process.

[joliecoeur13]

Originally Posted by Skint Eastwood

From Skookum, originally posted by Filtr

on this picture the wires going to the sk720 are bacwards !! bus B and C ??? or am I color blind ...

[georgi UK]

=] it's correct? each cable is carrying 3 connections, its a scheme so it only shows one trace.

[joliecoeur13]

Originally Posted by gmcallister

=] it's correct? each cable is carrying 3 connections, its a scheme so it only shows one trace.

yes but on my page the negative is on the other side !! on bus B -C ?? or less I'm loosing it , or sk is playing games ...

[msdavid]

SK720 Skookum FBL Unit
SK-PW 7 Skookum Power bus
OPTIMA 7 HITEC Telemetric RX
MUTIGOV PRO Aerospire Governor

Used the Optima 7's SPC connector for telemetric battery status monitoring.
CH5 Controls both, Cyclic and Gyro Banks.
Note that CH3 and CH6 are not as usual (CH3 THRO), I inverted them to give PITCH a higher priority in the Aurora 9.

Hope it helps.

[Doc-b]

Thanks for the Post. I will be trying this on 600N. I am hoping to us the Self level on 600N

[Doc-b]

I will be using your method,hoping it will keep my vibe levels low enough to use the self level on my 600N. Thanks for the post

[johnahamelv]

Originally Posted by msdavid

SK720 Skookum FBL Unit
SK-PW 7 Skookum Power bus
OPTIMA 7 HITEC Telemetric RX
MUTIGOV PRO Aerospire Governor

Used the Optima 7's SPC connector for telemetric battery status monitoring.
CH5 Controls both, Cyclic and Gyro Banks.
Note that CH3 and CH6 are not as usual (CH3 THRO), I inverted them to give PITCH a higher priority in the Aurora 9.

Hope it helps.

With your setup, do you have to connect a 2S Lipo to the SK-PW7? I am trying to figure out a way to just supply power with a BEC from the main pack, and not need a separate battery for the electronics. Thanks.

[onlocation]

Originally Posted by johnahamelv

With your setup, do you have to connect a 2S Lipo to the SK-PW7? I am trying to figure out a way to just supply power with a BEC from the main pack, and not need a separate battery for the electronics. Thanks.

Look at the little red mark on the power bus, this shows the 2 pins you tie together to run power all the way across the bus. With these pins connected you can run a single power supply from a BEC and it will power the entire power bus.

[johnahamelv]

Originally Posted by onlocation

Look at the little red mark on the power bus, this shows the 2 pins you tie together to run power all the way across the bus. With these pins connected you can run a single power supply from a BEC and it will power the entire power bus.

Will any of the pictured wiring setups work properly. My goal is to not have to use a separate 2S Lipo battery.

Photo1: BEC wires connected to Power BUS red and black wires. This would involve sacrificing the BEC servo connectors and some soldering, but the Power Bus empty slots would remain empty for future expansions, i.e. GPS.

Photo2: Power BUS red and black wires capped. BEC wires connected to Power BUS slots PWR-HV and PWR-LV. The problem that I have with this setup is that PWR-LV slot is isolated from the servos on the PWR-HV side of the grid. Only PWR-HV would be powering the servos.

Photo3: Power BUS red and black wires capped. BEC wires connected to BUS C and BUS D slots. I believe that this should work, but this setup would not leave me with ability to add future expansions.

Photo4: Power BUS red and black wires capped. BEC wires connected to BUS C and PWR-HV slots. I believe that this should work, and would leave BUS D slot free for a future expansion.

Please, critique.

Thanks.

[onlocation]

Originally Posted by johnahamelv

Please, critique.

Try to understand how the powerbus works and this will all make sense. You may want to read the power bus manual again and take off the case so you can understand exactly how it is working.

Basically the power bus is simply 2 power rails with servo signals distributed between them. If you only wish to use one voltage for your R/C equipment then you connect these 2 power rails into one rail by connecting the pins shown with the red wire in the drawing above. This makes the powerbus into one big common power rail, now you can plug your BEC into the big wires or into any open servo terminal.

[georgi UK]

=] does the vid help??! =

YouTube

YouTube

[johnahamelv]

Thanks. I did see the video before. However, the video uses a 2S Lipo as a power source, and only mentions the BEC for connection between the high and low voltage system.

It seems that in my case, I should connect the BEC to the red and black Power BUS wires, where the 2S Lipo would otherwise connect.

One concern that I have is that the SK-720 would only be powered by Power BUS A via the tiny current-limiting wires connected to the Tail slot of the SK-720. The SK-720 would in turn have to power the AR8000 receiver and the TM1000 telemetry. I hope that there is enough current via the tiny wires from Power BUS A to power all of these electronics.

[georgi UK]

=] the demand is on the servo side of the bus, you need to run a playback log to see the voltage drops here.

[dpelletier]

Here is my main power harness:


Two right most EC5 connectors are for the 5S LIPOs (in series for 10S power)
Servo type wire is to feed the SPC on the Optima 7 (5S = 18.5 volts nominal)

EC3 connector feeds 10S to BEC
Left EC5 feed 10S to the ESC

[dpelletier]

Now here is the whole mess (just missing the tail servo)



BEC is feeding 8.3volts to the Power-Bus for the servos and the electronics.