Basic Differential aka Tank Drive

With the Ratchet hardware build now complete, my developmental focus has turned to the software needed to run him. First up of course has to be getting him to move. The following post introduces a couple of basic scripts, one in C# (for the desktop) and the other in C (for Ratchet himself). The scripts have been developed to provide Ratchet with capability to calculate the speed and direction values needed for differential drive movement, both on and off the robot. ...more

Unity3D Serialport Script

This post presents a script and or prefab developed to allow drag and drop capability for serial communication within the Unity3D game development ecosystem. This in turn allows for the use of  custom gaming controllers and hardware developed on platforms such as Arduino and Netduino within Unity applications. The script is included at the end of the post and is also available for download. As always it is fully commented so that you can hopefully easily work out what is going on with the code. Events Update 06.03.2014 Please note that his script has been updated to both include event triggers and the removal of the threaded  update loop. For more information please see the post: Adding Events to the Serialport Script. ...more

Ratchet Headstock Assembly

Here we have another posting on the on-going build of my robot Ratchet. This time around I will detail the construction of the headstock assembly and present a simple script developed to help with the alignment of servos. The good news is, is that this is the final task in terms of hardware assembly. ...more

ServoBot LED Headlight & Sharp IR Bumper

In this post I will demonstrate the assembly of the bumper for my current robot build Ratchet. The bumper contains both a Sharp IR distance sensor (for obstacle avoidance) and a pair of LED's for headlights. One of the key features that I liked about my last robot build Sheldon was the use of flashing combinations of the headlights to indicate information such as current mode etc. I found it so useful that I decided to duplicate this functionality for Ratchet too. ...more

Arduino and the Sharp IR Proximity Sensor

In my last post I demonstrated how I modified a couple of Sharp IR sensors for use with my ServoBot Shield. It recently dawned on me however, that some of you might not know what these sensors are for, and how they are used. With that in mind I decided to put together this quick post as a bit of an introduction etc. Introducing the Sharp IR Sensor The Sharp IR family of proximity sensors are probably the most commonly used sensors by robot hobbyists. This is because they are inexpensive and are ideally suited to small robots. ...more

Sharp IR Servo Plug Tip

This post is really a tip rather than a tutorial. Within it I will demonstrate how I prepare sensors and components such as Sharp IR's to be compatible with the ServoBot Shield. Essentially all that's really going on here is the fitting of servo plugs so that whatever component can easily be plugged into the shield, and then removed again if necessary. I think that this is a really useful way of being able to connect sensors so that they can be changed  as I see fit whilst also ensuring that the connections are secure. ...more

The ServoBot Shield

Last month I published a post detailing the construction of a power harness for my servo based robots Ratchet and Clank. The harness is used to connect one of two battery sources to either an Arduino or a simple power distribution board (PDB). The PDB, much like its qauadcopter equivalent, is a simple board that is used to distribute power across each attached servo, whilst also breaking out each their signal lines so that they can easily be connected to the Arduino. During the publication of that post I began thinking; why have a separate board with all those wires? Why-not just put together a simple shield that does the same thing in a more compact manner? After toying around for a while with the idea I came up the design for my very first ever shield, The ServoBot Shield. ...more

The Cruciferous Vegetable Amplification

[one_half]For those of you not in the know: "The Cruciferous Vegetable Amplification" is the second episode of the fourth season of the American sitcom The Big Bang Theory. Within the episode one of the main protagonists (and my personal favourite),[/one_half] [one_half_last]Sheldon Cooper works out that he won't live long enough to download his consciousness into a robot body, and by way of result he then attempts to extend his lifespan by changing his diet and then developing the Mobile Virtual Presence Device (MVPD, fig 1).[/one_half_last] ...more

Ratchet & Clank – Power Harness

Today my attention turned towards a means of providing power for my servo based 3D printed robots, Ratchet & Clank. In order to achieve this I first off defined a list of requirements that any potential solution must fulfil: Separate power sources for both the servos and Arduino. Can be turned on via a single switch. Can power at least six servos. Luckily the circuit turned out to be dead easy. All I needed to do was tie together both of the ground wires coming from the battery and then wire them to the switch. The switch then provides the ground source for to two male servo plugs. Each plug is also connected to one of each of the positive lines. ...more