DFRobot Wheel Encoders for DFRobot 3PA and 4WD Rovers (2pk)

Install requires some work to space the encoder wheels with the plethora of washers and spacers provided. I have a different take on the discussion by another reviewer on the interrupts. You do get different counts based on the pin you connect to, but that is due to the Atmega interrupt scheme. Different chips have different interrupt architectures. Leonardo boards use the 32U4 chip, which have a dedicated interrupt signal on pins 2 and 3, while the UNO uses the 328 chip, which does not. If a pin does not have a dedicated interrupt, it gets lumped into a 'pin-change' interrupt with all the other digital pins that don't have dedicated interrupts. When I used a UNO board and pins 2 and 3, I would get 'cross-talk' between the wheels. It seems that the Arduino library gets the interrupt and tries to decide which registered callbacks should be invoked base on the pin states. If there are more than one 'pin-change' interrupt callback, it seems to be able to get confused. I solved this by manually checking for a pin change-of-state in the interrupt handlers. After doing this (and adding some debounce code as well), I got very consistent count numbers.

These are a little tricky to install on an assembled robot but the instructions are perfect. Once you try to use encoders comes the confusion, at least when using an Arduino mega. I found different readings per wheel and thought there was an encoder problem until I ran an experiment with different intercepts. Someone should write a tutorial on using encoders and intercepts. Here is what I found when using the same encoder at the same speed on different intercept pins: right encoder on intercept 0 (pin 2) Count = 148 right encoder on intercept 3 (pin 20) Count = 28 right encoder on intercept 2 (pin 21) CountA= 28 right encoder on intercept 4 (pin 19) Count = 1276 right encoder on intercept 5 (pin 18) Count = 908 Once you understand this you can make use of whatever formulas per encoder you need to achieve speed or distance results for the wheel pairs.

1. Vous ne pouvez pas installer le panneau arrière sur la plate-forme DFRobot 4WD Mobile avec ces capteurs fixés aux moteurs arrière. Je ferai éventuellement mon propre panneau arrière imprimé en 3D pour résoudre ce problème et la plaque supérieure / inférieure maintiendra le robot en place sans le panneau pour le moment. 2. Il y a beaucoup de redéclenchements / rebondissements du signal et pour me rapprocher du 20 CPR, j'utilise un anti-rebond glissant. Ignorez le temps de 12 000 us à vitesse maximale et supérieur pour les vitesses plus faibles. Je ne sais pas à quel point ces capteurs seront utiles pour surveiller avec précision la distance / la vitesse

Seem to do the job. Gives 5v signal when photo interrupter is blocked by the disk. So far they seem to work reliably. Does not mount on RB-Sbo-02 GM3 - Gear Motor 3 - 90 degree Shaft without modification.

Semble faire le travail. Donne un signal 5v lorsque l’interrupteur photo est bloqué par le disque. Jusqu'à présent, ils semblent fonctionner de manière fiable. Ne pas monter sur le RB-Sbo-02 GM3 - Motoréducteur 3 - Arbre à 90 degrés sans modification