Despite its strange name and appearance, Grockle, as we will from now on call him, does a very “unstrange” thing-line following. Grockle is a mars-type theme robot made with pieces from the RIS and Exploration Mars Expansion Set. He is carefully designed and is split into 6 sub-assemblies. All the sub-assemblies are very easy to take off and put on. This is known as modularity. For instance, the left part with the wheel is one whole sub-assembly that can easily be pulled straight off and put back on with the greatest of ease via 2 black friction pegs and an axle extender that connects directly to the main driving axle. The whole robot is very robust and sturdy with hardly a single weak spot because I made durability a high priority.
One priority I had in mind was speed. Not the robot's general speed, but how fast it could follow a line. I used things like a tricycle drive, a differential for the main driving, and an advanced programming language to try and get the most out of Grockle. For fun and to see how they would measure up, I programmed Grockle in 3 different programming languages: RCX Code, NQC, and Lejos-a firmware replacement programming language based on Java. I made around 30 test runs and some calculations to figure out how fast Grockle really went. Here is the deal: The INSIDE of the test mat is approximately 5.15 feet long. I timed the robot as I ran it around the whole test mat 3 times for each programming language and then divided by the total time it took to do it by 3 to get the simple average. Here is how it looks:
RCX Code: 10.60 sec., 10.42 sec., 10.65 sec., Avg.= 10.56 sec.
NQC: 10.57 sec., 10.27 sec., 10.38 sec., Avg.= 10.41 sec.
Lejos: 12.41 sec., 11.99 sec., 12.09 sec., Avg.= 12.16 sec.
NQC topped them all! I thought Lejos would make the test mat in the best times because the replacement firmware has a faster sampling rate of the sensors but it didn’t! This is due probably to the fact that Lejos doesn’t have until statements. Until statements are excellent for line following which is why NQC did so well. Instead, in Lejos I had to substitute either nested if statements or while statements. I also calculated their speed in feet/second. Here they are:
RCX Code: .49 ft./sec.
NQC: .50 ft./sec.
Lejos: .42 ft./sec
Although Grockle is definitely not the fastest possible configuration, he is a good example of what can be done when you take a “normal” concept-such as line following- and give the robot an imaginative twist to its looks and in the way it solves a particular problem. Thank you for looking! |
