Base completion with good control

[Russ76]

Robbie_Andino base one and two videos. Tried to follow all instructions and got the motor control working well here. Angular velocity may need more boost after other parts get added to robot and the weight increases. The Arduino PWM control is noisy! I prefer the Sabertooth for motor control and it uses higher frequency, beyond human hearing.

https://youtube.com/shorts/NxB7sZY-XKk

https://youtube.com/shorts/_mjRytEW1MA

[Russ76]

I wondered at the unusual wiring of the L298N in this repo. This note from https://www.pololu.com/product/1451 helps me understand what is happening. I could tell that the control was noisy, more than I was used to.

In this configuration, motor direction is determined by the states of the INA and INB pins and motor speed is controlled by the duty cycle of a PWM signal supplied to the driver’s PWM pin. The PWM pin is pulled low on the board, so the motor driver outputs are effectively disabled by default; the INA and INB pins are floating (they are not pulled to any particular default voltage). See the truth tables in the VNH5019A-E datasheet for more information on how the INA, INB, and PWM pins affect the driver outputs, OUTA and OUTB. Note that it is also possible to save a microcontroller I/O line by directly PWMing the INA and INB pins while holding the PWM pin high (e.g. by connecting it directly to VDD), but the trade-off is that this only works at low frequencies (a few hundred Hertz or less).

[francocipollone]

Hey there @Russ76 , according to the datasheet and assuming the wiring in the motor board is the correct the wiring in the andino looks ok.

Regarding freeing som I/O lines, you can save 2 lines by using two jumpers in the andino.

I haven't used the VNH5019 like to actually give an opinion regarding its particular connection. But it is true that probably the L298N is a bit old and using a newer motor driver might be even more beneficial (also the size for the new ones are smaller!)

[francocipollone]

Thanks for sharing the videos! It looks great!