Football Table Table: Difference between revisions
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Homing is two stage process, first rotational homing takes place after which the lateral direction is homed. Typically failure involves on of the following two cases. | Homing is two stage process, first rotational homing takes place after which the lateral direction is homed. Typically failure involves on of the following two cases. | ||
'''The rod keeps on rotating''' | '''The rod keeps on rotating, stops, and does not finish homing''' | ||
<p>This is the most common failure, it has to do with the homing sensor. This sensor in the rotational motor frame and detects the passing of a brass insert in the large white sprocket(s). If it succesfully detects this insert passing by, the led on the sensor will light up. If the led does not light up, then the likely cause is that the distance between the insert and the sensor is too large.</p> | |||
<p> | |||
This is cause by the fact that there is play in the rotating part of the rod, neccesary to keep the friction down. If we gently pull the rod towards the sensor and restart the homing, the problem will often be solved. You can test this ''without'' starting the <code>MOTION</code> executable, all that is needed is to have the amplifier on, by manually rotating the rod past the sensor and checking if the led lights up. | |||
</p> | |||
'''The rod finishes homing, but does not reach a central position''' | '''The rod finishes homing, but does not reach a central position''' | ||
Revision as of 11:42, 11 September 2013
How it works
The semi-automated foosball table has two DOF per rod.
Starting it up
Homing
Things to watch
Run-time
Transport
Maintenance
Replacing a cable
Common causes of error
Here we describe some common causes of error
Diagnostics
There is a log file available in the main folder, called MOTION.mat. Here the measured position and the sent control signal are beeing logged, but also the ball position estimated by the IMM/KM.
Poor overal performance
Symptoms: often loosing sight of the ball, missing the ball completely with attempting to shoot.
Bad performance, table soccer-wise is often too to bad detection/calibration. Take into account that changing lighting conditions have a significant impact on the overal performance of the localization. It is not uncommon that lighting conditions change significantly during a day, espicially in a room with direct sunlight.
A quick fix can often be achieved by adjusting the fluorescent lights over the table using the dimmer, to cope with the changed conditions. Similarly adjusting the exposure time (ET) can help. If changing the lighting conditions does not help, then it is advisable to fine-tune the color-calibration itself. When using the white ball, checking and fixing the mask positioning is also advisable.
Sometimes the position of the overhead camera changes during transport, which in turn messes up the camera calibration e.g. the distorion, the mask placement and espicially the rod positions. Symptons of this are e.g. a static offset when trying to hit the ball (whilst detection is good).To fix this one needs to quickly re-run the camera-calibration (not the color-calibration).
Failure in homing
Symptoms: one or more rods fail to reach a central/homed position on the table. However motion during homing is stable and controlled.
Homing is two stage process, first rotational homing takes place after which the lateral direction is homed. Typically failure involves on of the following two cases.
The rod keeps on rotating, stops, and does not finish homing
This is the most common failure, it has to do with the homing sensor. This sensor in the rotational motor frame and detects the passing of a brass insert in the large white sprocket(s). If it succesfully detects this insert passing by, the led on the sensor will light up. If the led does not light up, then the likely cause is that the distance between the insert and the sensor is too large.
This is cause by the fact that there is play in the rotating part of the rod, neccesary to keep the friction down. If we gently pull the rod towards the sensor and restart the homing, the problem will often be solved. You can test this without starting the MOTION executable, all that is needed is to have the amplifier on, by manually rotating the rod past the sensor and checking if the led lights up.
The rod finishes homing, but does not reach a central position
Loose sensor cable
Symptoms: puppet slams into the wall or spins out of control during run-time or homing, motion.mat shows encoder output to be zero.
A loose sensor cable will cause a dramatic failure,