*Parts fix and replacement [#t64a9929]
***Frame [#b97c310e]
-Frame is made from ABS resin using 3D printer
-But instance glue for ABS to adhere broken frames is much easier than remaking frame with 3D printer.
***Leg [#tab56efc]
-Leg is made from ABS resin using 3D printer
***Propeller [#rf49b200]
-Part number is HCB-03 and available from the following shop.


-Drilling the center of propeller is needed to extend hole to fit 1.5mm shaft length. By extending the hole with the following 1.44mm reamer, a propeller can be fit to a shaft of the motor without adhesive. 


-By default, HCB-03 propllers are very unbalanced and causes vibration. To solve this problem, tape adhesive can be used to calibrate moment balance.

-After replacing a propeller, variables of thrust bias should be set by changing following variables in /root/dirs/pc/code/base/pxlib.c
-After replacing a propeller, parameters of thrust bias should be set by changing following variables in /root/dirs/pc/code/base/pxlib.c
 //Set following varibales, normally ranging from -120 to 120.  
 //This setting strengthen left thrust(to go right)  
 addr_pconfig->duty_bias_upper = 0;  
 addr_pconfig->duty_bias_lower = 0;
 addr_pconfig->duty_bias_left = 60;
 addr_pconfig->duty_bias_right = -60;
After changing those variables, the program must be compiled again.(see [[User Program Manual]])

***Motor [#r25ff66a]
-Part number is AP-03 and available from the following shop.


***Sonar sensor [#wa0e8ae1]
-Part number is LV-MaxSonar-EZ1 and available from the following shop.

-The sonar sensor is very weak to vibration cased by Phenox(Impulse noise is observed without gel tape).

***Micro SD card [#h839bd5f]
-Part number is TS4GUSDC4 at kickstarter model in May 2014.
--Boot successful rate of the current model depends on micro SD card part number.([[known issue>#bec29918]]) 
-save backup with following command (replace sdd and path to fit user's environment).
 sudo dd if=/dev/sdd of=~/sdback.dd
-copy backup to new micri SD card with following command(rewite /dev/sd* and path to fit user's environment).
 sudo dd if=~/sdback.dd of=/dev/sdd bs=1024k

*Maintainance [#yaeffd5c]
-Phenox needs maintainces after some flight.Please check following points
+Tighten 18 screws of 4 motors(12 screws), the camera(2 screws), 4 legs(4 screws).
+Sonar location and cable disconnection check.
+Check sensor state using tutorial_selfstate(see [[Tutorials]])
+Save backup of micro SD card.(see [[here>#t64a9929]])
+Check propellers are not loose.
+Check motors rotate smoothly. 

*Known issue [#bec29918]

**Boot from micro SD card fails irregularly. [#ze28bdb1]
-This problem is caused by dependency of Phenox firmware system and micro SD card.
-We observes two cases that boot fails. 
+Red led doesn't turn off (before executing u-boot)
+Reading sector error of MMC (when u-boot reads contents of micro SD card)
**Incomplete images are sometimes acuquired (green images) [#sa0e241b]
-This problem seems to be caused by miss-synchronization between camera and Phenox, and is under examination.
-This issue depends on initialization states, so if users acquire normal image from both cameras, image acquisition is normal until shutdown. 
-Self position estimation becomes very slow(insensitive to self-movement) when this problem occurs.
**Impulse noise is observed in mic. [#i22ef983]
-This signal is caused by sonar sensor, which is sending ultrasonic signal to measure height. 
-Will be fixed at next revision.
**Wrong height control. [#h9561cb8]
-The source of this problem is mostly sonar sensor.
+Impulse noise caused by vibration
--Users can check this noise by monitoring selfstate(see tutorial_selfstate of [[Tutorials]])
--inserting gel-tape improves this problem.
+Stationaly wrong height value
--Check connection of a sonar sensor.
--In our experiment, some sonar sensors are broken with direct physical shock such as dropping Phenox on the ground without legs.

Front page   Edit Diff Backup Upload Copy Rename Reload   New List of pages Search Recent changes   Help   RSS of recent changes