BEAM which stands for Biological Electronic Aesthetic Mechanics is the brainchild of Mark Tilden from the early nineties.
BEAM is an interesting robotic building mantra: keep it simple, make it cheap, make it modeled after nature, (see also Tilden’s Law of Robotics).
Many companies offer kits, parts, schematics, and various other bits and bobbles pertinent to the average BEAM Robotic enthusiast. Since these robots were originally built from scrap parts, its fairly easy to find components. Designs and schematics for the original engines exist on the Internet; I need not list them here.
The above little beastie was is a kit purchased from Solarbotics, one of the first (from what I recall) BEAM suppliers to release kits as far back as I can remember being involved with BEAM (high school…? mid 1990’s).
BEAM does not have to always be solar powered, but robots are usually coupled to light as a “food” source. BEAM relies on a series of high level intelligence behaviors expressed in extremely simple logical blocks.
For example, here is the thought pattern of this little bot:
- Charge (collect food) while resting
- Decide good light direction (left or right, which is better?)
- Burst motion toward light
- Rest and Repeat
In short, the solar panel collects light, charging a capacitor. When the capacitor charges to specific voltage, a transistor flips and discharges, resulting in forward motion. Various decision tools are also in place, such as touch sensors and light optimizing and infrared sensors which both influence the directional drive motors.
For my first BEAM Robot, I chose old-school “classic”, from the days when I first heard about Tilden and BEAM Robotics. I ordered a Photopopper Photovore 5 kit from Solarbotics on Sunday for ~45 USD.
I had it shipped overnight, which impressively passed US Customs and arrived Tuesday at 10am. This is what it looks like when unwrapped:
Inside the numerous little plastic baggies, one will not find a scary, small town electronics department. As you can see in the image below, its pretty spartan.
The kit consists of two complete cores, sharing only the collecting solar array, and the storage capacitor. Considering that the most advanced component shown below is essentially an on off switch, its fairly simple.
Here are some random snaps of the bare mainboard. Its kinda cool how it curves, and that is the sort of detail mere hardware-hacking mortals can’t match without quite a bit of work fun in the garage.
I can understand if some die hard individuals think this is “cheating”, but this is a good honest way to get into the hobby of BEAM. I recall personally that when my amount of free time exceeded my amount of free money, things were different. I must argue the point that while maybe I did not learn as much as someone who built one from scratch, I made many false starts back then. So many so that I had to put it down!
The above pictures show the front and side view of the mainboard. While this is repeatable by the average enthusiast, the quality of the kit is impressive.
The curvature of the mainboard is a very innoavative design, adding a “spine” to the creature and eliminating needless parts. This extends the spirit of BEAM, which is to utilize as few components as possible, often creating interesting electro-mechanical relationships not formed anywhere else.
You of course need a few extra tools as well. A good quality, low wattage soldering iron and solder, wire strippers, needle nose pliers, and a solder sucker (in case you mess up). Here is a picture of all the bits, and of all the tools I used.
Enough pictures of the kit! We Build!
The kit instructions are well written, I can imagine it being acceptably entertaining and understandable to younger audiences. The manual shows history of BEAM, detailed schematics, as well as a step by step walkthrough with pictures at every step. In a nutshell, one orients the component properly for polarity, pushes the solid wire leads through the board, and bend them over gently. Prior to bending, trim excess wire to make it look pretty, and prevent shorts.
Once your satisfied with your placement, solder it in place. Remember, heat the part (not the solder), but not to much or it will cook the component.
Generally with the components, when you finish one side you mirror on the other. Lather, Rinse, Repeat!
The kit proceeds fairly fast through similar of activities. Near the end, the solar panel is soldered in place. Once this step is complete, your robot is permanently active whenever light is present.
On the bottom of the bot, a potentiometer resistor aka “POT” controls left and right bias. Mine was extremely right bias, and it took many turns to correctly have my bot track correctly to light.
After the solar panel is in place, one could stop and enjoy the robot without any further work. The next, and probably trickiest part, is adding the tactile sensors. The tactile sensors are designed to short motor controls to power opposing motors to direct away from objects.
Gotchas
Like the previous portion mentioned, I had some difficulties adjusting the potentiometer. This made my critter run around in circles, until I could turn the little adjustment screw what felt like 20 turns back to center.
Another annoyance was on the fuse holder feet, which hold the motor to the circuit board, I broke off one of the metal attachment hooks. As a somewhat seasoned hardware hacker, I didn’t skip a beat, and soldered it back on. Good as new. Maybe better. This small setback made me think critically about the kit to first time builders, as it might frustrate and draw people away.
One final annoyance, the “wings” on the circuit board were a little fragile. One of them cracked a little, making me rethink the cool-factor about the bent circuit board.
Still kinda cool though. I dig it, and I would buy a kit as a gift for someone 16+
Disclaimer: I’m not paid or compensated in any way by Solarbotics or any of the other companies listed here. Solarbotics is probably a registered trademark of its parent corporation or company. Go buy the product, don’t copy the board and design.
Happy BEAMing!