My Robots are constantly evolving, so expect to see changes in the various pictures. For example, Loki started with no arms, a different head, and stepper motors for the wheels.
To see details of Loki construction, select one of the links below:
Loki Current Design
Loki Arm Design
Loki Head Design
Loki Frame Design
Loki Early Head





Dave,
I am in the process of contructing my bot named Herbert. I noticed you drive Loki’s arms using a chain and sprocket set with a geared DC motor for activation. In Herbert, I want to use stepping motors for activation and have already built and tested the controllers. My question is first, where did you get the chain and sprockets? Second, I was also thinking of perhaps using either a worm gear drive for the arm or a spur gear setup, or simply a bevel gear setup. Any reason for sprockets? In any case, please let me know who your supplier was.
Thanks
Bob
Hi Bob,
If you have a website, post a link here. I’d love to see how Herbert progresses!
For the gears, I had bought some Pittman motors cheap on eBay, and needed to gear them down a little more than they were.
I built the gear box because I thought it would give me good torque at the right speed, with smooth operation.
I wanted the motors mounted low on the body, so I used a chain.
It works pretty good, but I think a direct gear drive to the chain would be better. I hadn’t considered a worm drive.
On the plus side, a worm drive would mean the robot arm would stay in whatever position placed with no current load. But, on the downside,I find I move the arms manually a lot while working on the robot; that would be hard to do if the arms are connected to a worm drive, I think? You might need some sort of “release” pin or something.
I’m not sure, but I think this is where I got my chains and sprockets. As I recall, I went down a size from standard bike chain.
http://www.electricscooterparts.com/sprockets.html
Best,
Dave Shinsel
Thanks for the info Dave.
I don’t have a web site yet; but the project group I am working in has a yahoo group.
Herbert is one of the LEAF project robots and they have several sites with the robots that various members have built.
Also, LEAF software is mostly programmed in LISP.
Thanks again, and I will let you know how I progress.
Bob (and Herbert)
Hi,
I love your robot. I’m making a robot base right noe and eventually a arm for it. It will be designed mostly for outside and the primary goal is to have it take out the garbage and to explore the the yard. Here is a question for you. What is the upper blue metal from. Seems like it would make a good upper arm like you used it for.
Great job by the way.
Jon