ORC-KIT with standalone H-Bridge Drivers (and some updates)

So in the sort of tutorial I wrote about ORC-KIT I mentioned that it was possible to use other boards instead of Adafruit’s friendly motor shield, and in fact, there was space in the board for a couple of very cheap and widely available L9110S Dual H-Bridges, which should give you more control over the build, and “free” some precious Arduino pins that you can use for extra sensors and actuators. You can actually change the Arduino for something else, but that’s beyond the scope of this post.

H-Bridge?

H-Bridges are simple circuits that allow you to control the flow of current through a “load” with 2 control signals (A and B). When the load is a motor, you can make it spin forward, reverse or stop completely by changing the digital values on A and B. H-Bridges normally have an ENABLE line as well, which you can toggle yourself or leave permanently “ON”. Controlling the speed of the motors is easier if you can turn each bridge on and off quickly using PWM pulses applied to the enable lines, but that’s not always possible. The L9110S boards don’t have an enable pin, for instance, so we will need to manipulate only the 2 basic control signals to drive our motors if we use this controller.

Each of these Dual H-Bridge modules can drive 2 motors and has a 6 pin header for the 4 control signals plus power.

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Introducing ORC-KIT!

Earlier this year I embarked on the journey of designing a simple but expandable robot that any electronics enthusiast could build. I knew several nice kits from brands like LegoMakeblock, OWI Robotics, etc, but I considered them to be normally either too expensive or too simple and limited. There are also many generic unbranded kits on eBay which suspiciously have all pretty much the same design but vary mostly in their debatable choices for hardware and layout.

I wanted to do something flexible but not too expensive nor flashy, much like the unbranded kits, but with better design practices in mind, and engineered to be heavily customizable.

Fully assembled Vanilla ORC-KIT with some extras.

Fully assembled Vanilla ORC-KIT with some extras.

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