Is anyone using gov?

[Ricoman (maphe)]

The topic is over

thanks

[ChrisOlson]

I used to use the Aerospire. If you read the instructions for it, it requires a throttle curve to work properly. Without the throttle curve if the speed sensor or governor fails in flight you will lose throttle control and go to fixed throttle, whatever is set by the SETPOINT with Mode 2. This is not a good idea because combustion engines cannot function on fixed throttle. It would be like jamming the gas pedal in your car at a fixed value, then try to drive it. The throttle must change in response to load on the engine, and the load is not constant. When you land, for instance, and drop pitch the engine will grossly overspeed and cause damage to it. In flight, even making a turn with the heli will cause loss of headspeed and tail authority due to increased loading with the throttle jammed at a constant value.

The instructions on setup of the Aerospire are pretty clear in the manual that comes with it. If the rpm is all over the place on throttle curve, you either don’t have your throttle curve tuned properly, or you don’t have the gains set properly in the governor. The first step before flying any combustion engine governor is to first tune the throttle curve so the helicopter flies properly from takeoff to landing just on the throttle curve. Then you can engage your governor and tune the gains in the governor.

Edit:
The reason I don’t use the Aerospire anymore is because I wrote an internal rotor speed governor for ArduPilot:

Helicopter Rotor Speed Governor

We’ve been working on a governor for ArduPilot and I now have it working pretty good: I have test binaries built for various controllers. All the builds are ChibiOS: The governor measures headspeed, not engine speed. It requires a hall effect sensor with a magnet on the main or autorotation gear. The sensor is plugged into the Aux5 pins on your controller. The settings to get RPM to work are the PWM count - set to 4 so aux5 or 6 can be used for other things. [Settings2] The relay pins disa…

The ArduPilot governor is not yet in master but it was many weeks in development and has been thoroughly tested and flown. There are builds for it on both Copter 3.6 and 3.5 so other folks can fly it with combustion engine heli’s, and several users are already flying it. Note it is a rotor speed governor designed to measure main rotor speed, not engine speed. I have experienced a high rate of failure of engine speed sensors in the past due to the heat and vibration they are subjected to on piston engines, usually in close proximity to the magneto. I have never had one fail placing the speed sensor in a less severe environment, measuring rotor speed.

[blue0827ww (chen pu sheng)]

@Helicopter Rotor Speed Governor Traditional Helicopter

This governor was designed primarily for piston and turbine helicopters, as the engines don’t come with a governor (except for JetCat turbines) and buying one is quite expensive.But it does also work with electric helicopters - I tested it in my Synergy 626. The only difference with electric is the droop response setting. Electric motors have a quite flat torque curve so they don’t require as much droop response as combustion engines. However, unlike combustion engines, the speed of an electric motor droops as the battery voltage falls. This is where the governor will come in handy for an electric (if your ESC don’t have one).

Since most people use ESC’s with governor already built-in, I suspect the governor feature will be primarily used by people who fly pistons or Wren turbines.

I would like to ask a very stupid question, if you use the electric motor h_rsc_mode=4 mode, do you need to install Hall sensors and magnets on the head of the helicopter?

[bnsgeyer (Bill Geyer)]

Thats not a stupid question. Yes Unfortunately, you will have to install a Hall effects sensor and magnets as the governor is tied to RPM 1 in the code. If at some point, esc data could be used for RPM 1 then it would be possible to use the esc speed and not a sensor.

[blue0827ww (chen pu sheng)]

@bnsgeyer

If at some point, esc data could be used for RPM 1

Do you mean to insert the ESC GOV line directly into AUX5 and display the ESC speed on RPM1 (so there is no need to install a magnet + Hall sensor)

[bnsgeyer (Bill Geyer)]

From what I gather, some ESCs can provide data back to the controller. Most likely the code would need to be changed to make use of that data for the internal heli governor. For now, you will need a Hall effect sensor