Servo - April 2009

Bug Sport

hairpin turns with the mix and match line-following track. While one bug is tons of fun, we thought a second bug would be a great addition to the family. We decided to build the grasshopper out of a second kit (a single kit contains two motors, which is enough for only one bug at a time). We were drawn to the grasshopper because of the antenna that seemed to defy gravity. The construction of the grasshopper is quite similar to that of the ladybug, even though the base is slightly modified.

The charming antenna are given their shape by an innovative little assembly that uses interlocking serrations to provide an adjustable joint that stays in place fairly nicely. These joints are the secret to many of the insect-like details on the Ollo Bugs, and while they certainly seem robust at first blush it remains to be seen if they will be able to hold up after prolonged usage. We think that they would, but one has to remember that these bugs are going to face some serious wear and tear at the hands of the intended audience.

Splattered

After building the ladybug, the grasshopper went together quickly, and we were ready to test the new specimen. We were excited to see the grasshopper work because the leg design is slightly different than that of the other bugs, with longer back legs to more accurately represent its insect inspiration.

You can imagine our disappointment when we first activated the grasshopper robot only to discover that it sorely lacked the agility that would earn it props from a martial arts master. The basic problem was easy to see – one of the motors was not functional, and the intrepid insect could only move in a wide circle despite its most sincere efforts.

We resolved to try out some insect surgery. The first step would be to disassemble the grasshopper to the point where we could remove the motor. This, unfortunately, was almost to the point of complete disassembly,

but we readied our Ollo Tool and set to work. That is one disadvantage of the Ollo kit – disassembly of the bugs is not as quick as one might hope. The parts themselves can snap apart fairly easily, but removing the rivets and sleeves properly can require individual attention that can become somewhat time-consuming.

Once the motor was freed, we were able to give it a thorough inspection. We began our investigation with the classic technique of jiggling the wires to see if there was a loose connection on the end with the connector or at the end that connected to the motor itself. When our jiggling provided no answers, we were forced to look elsewhere for the cause of the problem. We even went so far as to take the motor apart to see if anything was jamming the gears, but we found nothing. After doing our best to clean out the gears, the motor would actually move, but it would not start without a little helping hand. When reattached in the leg assembly, the motor would not start, and we were forced to bid farewell to our dreams of an epic bug battle. We must make it clear, though, that problems with motor modules are not phenomena confined to the Ollo Bugs. We’ve had similar experiences