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View Full Version : Testing the new CSM RL30 with collective management


jsenicka
06-05-2008, 01:11 PM
Howdy all
Thought I would share some very positive feedback on the new CSM RL30 Governor, with Collective Management.

A month or two back I upgraded 2 of my Raptor 90's to the new Kasama Srimok head.
http://www.helifreak.com/showthread.php?t=75618

I am currently configured with +/- 13.5 degrees collective and +/- 8.5 on cyclic. The Kasama Srimok makes the R90 a brand new bird. It will change direction in a heartbeat, and overall collective pop is amazing. That said, it also pushes my somewhat limited collective management to the limit as I start to toss it around. The CarbSmart on my OS 91SZ gives me fantastic power. I can climb out at near full collective like a rocket ship. Add in cyclic with that much pitch and even a perfectly tuned motor is going to bog. I can do pretty good managing pulling off the collective as needed in cyclic maneuvers, and am getting better at using only the pitch I need, but if I were better I would have to give up my day job

So on one of my more recent trips to Grand RC, Ed mentioned the new CSM RL30 with on board collective management. http://www.grandrc.com/inc/sdetail/125602 . It is designed to pull off a configurable amount of collective pitch when the motor drops below target RPM, and the engine is at WOT. It takes no action when the engine is inside target RPM, or in cases where the governor is disengaged during an auto.

The CSM sales literature says:

The RL30 has all the accuracy, ease of installation and flexibility for which RevLocks are renowned. But now, when you reach the limits of the power output of the engine, RL30 automatically modulates the maximum collective pitch available to prevent the engine becoming bogged down. With RL30 your can use more collective pitch range than with a conventional governor. You get higher flight speeds and snappier transient high g maneuverability. In sustained high g and high cyclic situations RL30 almost imperceptibly regulates the maximum collective pitch to keep your engine in the power band leaving you to concentrate on the flying.


Who could pass that up??

I removed my existing RL10 Revlock from 2 of the Raptor 90's and installed the RL30 in the same location. Initial setup was simple, as I only had to run the quick setup routine to teach the RL30 my throttle idle and WOT settings, and configure it to use a digital throttle servo. I then cycled power and set the A and B mode RPM base RPM to 14k for each band. For those of you not familiar with the RL series governors, they work by using the governor gain channel to select an RPM offset from a base RPM. This gives finer grain control that governors that use gain to control the entire RPM band. The base RPM available are 8k, 11k, 14k and 17k. The gain setting adds to the base mode. Settings one way from center on the gain channel select A mode and opposite selects B mode. Since I want something in the 14K+ range at all times on my 91SZ, and less than 17k, I can use both A and B mode with a base RPM of 14k, plus some offset.

What I wanted to accomplish was a way to have the RL30 collective management be able to be controlled from my transmitter so I could fly with collective management on and off on back to back maneuvers so I could see how well it worked.

This is really quite simple. First I programmed my governor control setup to give me an identical RPM in both switch positions. On my 9Z WC2, I use the front panel switch C (long toggle above cyclic stick) to switch between Governor band B (switch up), Governor disabled (switch center) and Governor Band A (switch down). Looking at my end points, you can see 39% gain in each direction. With my RL10 and RL30 setup to run 14k base, this translates to 15,750 RPM in either mode.

http://www.helifreak.com/attachment.php?attachmentid=50348&d=1212685382


Next we use the PC interface on the RL30 to setup the collective management parameters. You need the USB or parallel programming cable from the CSM 560, 630, 720, etc series gyros. You can pull the software from http://www.rcmodels.org/csm
Load the RL30 program on your computer, with the cable disconnected from the RL30 end. Power up your transmitter and the heli. Do not bypass the sensor check, as you can only interface with the RL30 while the sensor light is blinking. If you try to connect with the sensor test complete, it will give you a "Cannot connect to firmware ID 0" error. With the RL30 powered up, plug in the PC Cable, then click on "read from governor on the RL30 control program".
This is a screen shot of my near complete setup.
http://www.helifreak.com/attachment.php?attachmentid=50349&d=1212685382

In the right hand column, you can see my collective management settings. The collective pull off gain defaults to 50%. This is how aggressively the RL responds to a decrease in head speed at WOT. 50% works very well. If you increase too much it will lead to hunting, and to low and it will be slow to correct bogging.
The next value sets how much the RL30 can modulate your collective pitch. The default collective pull off limit is 19.8%. I increased this to 25% to give the RL30 the authority to take me from 13.5 degrees max pitch to as low as 10 degrees if needed.
The final value sets how far off of target RPM you want to allow before the collective management cuts in. I left this at the 1.5% default.

The center column is my A band settings that are active when I flip the C switch to the down position. Here the governor is active, but the collective management has zero authority to change collective pitch. This was for my side by side comparison.


In flight, this thing is way cool. With the collective management engaged, I need to work very hard to get an appreciable bogging. My SZ will pretty much sustain a full 13.5 degree climb out, but it bogs quickly if I feed in cyclic. With the RL30 active, I can do a full pitch climb, and maneuver the heli with authority. It is easy to do silly stuff like tight flips while climbing, or massive barrel rolls. with full collective engaged.

Where it really shines is in Tic Tocs and such where collective management really comes in to play. I can pop in a huge blip of collective if I want, and know that the RL will modulate some back out once I have changed direction. Essentially the RL collective management allows me to make full use of the inertia in the Radix 710's but prevents me from over drawing the inertia bank and paying the over draw penalty in spool up time!

I do not think the RL30 is magic. You still need reasonable collective management, as even with collective pulled to 10 degrees, I still have 8.5 of cyclic on tap. What it does is removes the need for super precision control in demanding maneuvers and just lets me fly.

I have about 20 flights in so far, and have tried with RL30 collective management engaged and disabled. For normal flying, I really do not see a major difference, as I am typically inside the power capability of the engine. Where it shows a major difference is shifting to 3D flying and starting to slam the heli around harder. Here I see a huge difference in available power, as it is much harder to induce a bog, so I always have pretty much the full 1900RPM available on the head.

I had Ricardo (Freya_Man) beating the snot out of one of the R90's last weekend. He is a far better 3D pilot than me, and while he rarely bogs the heli anyway, he was able to get far more aggressive with piros and tictocs without thinking of head speed.

Overall I consider this one a winner. I love the RL10 and RL20 to begin with, and for a very reasonable additional cost I can have something that actually offloads some of the mental load as I fly harder and harder. I purchased 5 RL30 units from Grand RC to completely retrofit my fleet. http://www.grandrc.com/inc/sdetail/125602 Give Ed at Grand RC a call and he will get you set up!


Feel free to drop me a PM if you have any questions

jim