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LEGO Mindstorms Vision Command

In September 2000 LEGO released their next major addition to Mindstorms, the Vision Command. Vision Command (VC) is basically a USB digital camera with some simple image recognition software in the LEGO Mindstorms interface design. Vision Command also comes with 141 new LEGO pieces to augment the Mindstorms set. So, is this just a little LEGO gimmick?

The Hardware

NO! I must say that the VC must have been one of the best buys (especially since I got £20 off the retail price) I've made in a long time. The camera is actually a Logitech QuickCam in a LEGO casing - it even has a built-in microphone. VC comes with some simple software that allows you to use your camera outside of the actual Vision Command software, but I'll explain the real potential of the camera a little later on.

The camera returns real-time video at 160x120, 320x240, or 640x480 resolutions. It can capture videos and still-images very easily. In fact, still pictures can be instantly captured using the button on the top of the camera. Below is a picture of a Boebot that the LEGO Cam took:

The camera also allows you to set-up various animation settings so you can do time-lapse animations (such as sunrise videos) or stop-motion (like those claymation movies). It already sounds like a decent setup, but combine it with the RCX, motors, light and touch sensors that come with the RIS, you can have some serious fun!

The Software

The software is done in the same point-and-click style that the RCX can be programmed in. The camera image is partitioned up into a possible 8 different regions. You then specify what type of attribute to assign to the region: colour-sensitive, motion-sensitive or light-sensitive. Then you can create the list of commands using the drag-and-drop interface to create quite complex programs.

It is really quite easy to create fairly cool programs from relatively simple code. For example, create a program that tracks you as you move around the room simply involves selecting a 8-region vertical split, and telling every region that is off-centre to move the camera a little amount. By tweaking the sensitivity of the motion detection, you can create quite an impressive motion tracker in 15 minutes (after power stand has been built). Here are some shots of the interface:

The interface is impressive, and will suffice for your average hobbyist. Here at Generation5, we enjoy hacking the hardware and software a little more to see what it can really do - especially with an application to Artificial Intelligence. Does VC have what it takes to become an asset to the budding AI enthusiast?

Expanding the VC

Since the LEGO cam is a Logitech QuickCam, you can download the Logitech QuickCam SDK and access it through an ActiveX control, allowing you to add video immediately to any of your ActiveX-enabled applications! This means that by buying a VC kit, you set your self up to experiment with image recognition, motion detection and analysis, face recognition and a vast array of additional goodies. Granted, this has nothing to do with Vision Command itself, but it is an excellent side-effect to the product!

VC also only comes with 20 present region definitions. Some of these are good for some tasks, but not for others. Luckily, it is relatively simple (albeit awkward) to create your own regions. This is actually one downpoint of VC - I really would have liked to see a region-creator bundled with the software, even if it was just a powertool not integrated into the main VC program. Nevertheless, creating your own regions is possible.

VC also requires the next version of the firmware to be downloaded on to the RCX. This is supported by the RCX2.0 SDK (currently in Beta stage). This new SDK uses ATL and MindScript to control the RCX - MindScript is a scripted language that the next version of RIS will support. Basically, anything written in the interface will be converted into MindScript (like MindRover with ICE). So, while v2.0 of the RIS isn't out yet, we have all the tools necessary to start supporting it - LEGO definitely have the right idea here.

Conclusion

VC is definitely something to enjoy - if you stick to the standard LEGO interface, you can still create some interesting things - a remote control camera (well, the camera is connected by the USB cable, but the motors aren't wired to the computer!), a motion tracker, a security alarm, a colour sorter and more. If you hack a little bit and make your own regions, you can expand to things like a line-follower, a music reader and more. If you want to start messing with the Logitech SDK your possibilities are endless. Combine it with the Spirit OCX control you can control any robot attached to the camera, and process the camera input yourself, making your robot behaviour much more complicated. Excellent stuff!

Vision Command is definitely a top-notch product, and while VC doesn't require RIS, you are missing out on 50% of the fun without it. If you have the RIS kit and have a little spare cash, definitely invest in Vision Command.

Cover 9.1

Price: £79.99

Liked: A complete Logitech camera, decent support software, great idea.

Disliked: No region creator.

Last Updated: 16/01/2002

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