Advanced camera platform

Hi everyone

I have been sitting on the fence trying to decide if I should get myself a Multipilot32 system.

I am currently using the Standard Arducopter2 boards with the 2.0.37 code. I have been very pleased with it thus far. I always want to take things to the limit of current technology as I use my specially designed copters for advanced aerial filming work.

When I played with my MK boards I ended up with 67 deg/sec gyros instead of the AD610's It took some work but the stabilisation of the model was much better. Naturally one had to cage the inputs to stay within the FSR of that type of gyro. Acro modes are not something that interests me as my goal is to create the ultimate super stable model which provides the base from which a very highly stabilised camera mount can operate.

My next experiment will be to change the gyros on the arducopter from the ISZ-500 Yaw

to a ISZ-1215 which is a 67 deg/sec FSR gyro and for X&Y the IDG-500 for a IDG-1123 which is 43deg/sec FSR

I have seen very big improvements in camera mount stability by using these high sensitivity gyros so I do believe that by taking this step it will reduce the latency in the response time during the super stable mode of flight.

So my next question is this. Will the Multipitot32 board provide any benefits over the Arducopter2 stuff that I am now using.

FMC-4f.gif

Hi Denny,

welcome to FoxTeam :) So I understand your change in the MK . With 67 deg/s you have more resolution on mk because mk have only 10 bit adc on 644p micro . On MP32 you have 12 bit adc so you have a resolution of 4096 step instead of 1024. Do you have some video about your test ?

MP32 is more powerfull of APM . It's a 32 bit cpu with 70 mhz of clock around 100 DMIPS .

MP32 have 12 bit analog input , and we're working on different imu for it : VRIMU full is first product that we developed . Now is available VR Imu light analog and digital. The VRIMU full is available with ADXRS 610 with 12 bit of resolution instead of 10 bit as MK , so you have more resolution .

MP32 + VRIMU FULL ADXRS610 300 / 4096 = 0,07 deg/s of resolution

MK 300/ 1024 = 0,29 deg/s

MK 67/1024 = 0,065 is similar of 0,07 of MP32 + VRIMU with ARXRS610 but you have more range for standard fly.

check this link for more information :

http://www.virtualrobotix.com/page/multipilot32-1

http://www.virtualrobotix.com/pages/vr-imu-10

Best

Roberto

Replies

Denny Rowland July 28, 2011 at 4:50am

TLD | Zdenek Kalal

Part-2 Post Stab. not spoken here on Vimeo I am working on a new video that shows how I got to .005 degrees of stabilisation.

Here are old videos on vimeo. some of this you may find interesting I have been an aerial cameraman for about thirty years now. Making stabilised camera mounts has always been my job. The quest for models to take over this job is now a high priority with me.

BTW Some of that watersports was shot in Italy!

Some thoughts on controlling the camera mount for your information.

The most natural way to control the camera is to have the main control sick centralised with a spring as is normal with RC but the camera mount moves in direct speed to the amount that you move the stick away from neutral. It stops the movement once the stick returns to neutral slowing down gradually in the process. The camera mount has now found a new place to park.

This is done quite simply by locking the servos pot. at 1520 us. The imu is thus the controller.
- Denny Rowland > Denny Rowland August 24, 2011 at 1:06am
  
  The camera control described is usually known as slew mode. The main difference is that the imu is controlling the neutral position once it is parked. If the IMU has any drift then that position will also move around especially after a disturbance so for a dedicated camera IMU. I am suggesting that you need to have IDG-1150 for X and Y and IZS-1215 for Z axis. used as a stand alone or satellite sensor input. plus some attention to deadband features.
Denny Rowland July 27, 2011 at 10:29pm

Roberto

Thanks for that info I think I will get one.

On your new IMU board did you consider that It would be possible to have another set of gyros for the Super Stable mode. (Switchable) I needed a model that could be caged to operate within less than twenty deg/sec so that the camera IMU which uses the IDG1150 two axis gyro and is only 20deg/sec Full Scale Range can operate without saturation. With the 20 deg/sec gyro + 4096 then .005 degrees of stabilised resolution are thus possible. As camera movements are not much use if they are directed at more than 5 degrees per second the 20 deg/sec limitation may not seem to be as tight as may be first thought.

I would like to be able to move away from the stand alone camera IMU and have it integrated on the FC imu board. This will never be quite as accurate as having it on the camera base plate but with modern cameras moving towards internal optic flow technology it will not need to be so refined.
- Roberto Navoni > Denny Rowland July 27, 2011 at 11:10pm
  
  Hi Denny,
  
  so i'm working on different project . One project is to have a complete indipendent Imu control for professional 3 axis gimbal. So I can assemble imu with different kind of sensor without problem.So we can use also gyro with more precision an minor full range.
  
  In our imu we can control the temperature of sensor and compensate it.
  
  Do you have some sample about the fly of your quad , and a video of your result wit stabilization ?
  
  We have a group of people insite the university of milan . That are working on video stabilization algorithm using optical flow on opencv library. Are you have som expertise on this task ?
  
  Best
  
  Roberto
Roberto Navoni July 27, 2011 at 6:46pm

Hi Denny,

welcome to FoxTeam :) So I understand your change in the MK . With 67 deg/s you have more resolution on mk because mk have only 10 bit adc on 644p micro . On MP32 you have 12 bit adc so you have a resolution of 4096 step instead of 1024. Do you have some video about your test ?

MP32 is more powerfull of APM . It's a 32 bit cpu with 70 mhz of clock around 100 DMIPS .

MP32 have 12 bit analog input , and we're working on different imu for it : VRIMU full is first product that we developed . Now is available VR Imu light analog and digital. The VRIMU full is available with ADXRS 610 with 12 bit of resolution instead of 10 bit as MK , so you have more resolution .

MP32 + VRIMU FULL ADXRS610 300 / 4096 = 0,07 deg/s of resolution

MK 300/ 1024 = 0,29 deg/s

MK 67/1024 = 0,065 is similar of 0,07 of MP32 + VRIMU with ARXRS610 but you have more range for standard fly.

check this link for more information :

http://www.virtualrobotix.com/page/multipilot32-1

http://www.virtualrobotix.com/pages/vr-imu-10

Best

Roberto

This reply was deleted.