Maker Faire!
I will be at the Bay Area Maker Faire on Saturday, May 18th, all day. Also, I will be giving a presentation on the “Meet the Makers” stage.
Follow me on Twitter at @DaveShinsel
Robot Combat League Champions!
Dave and his daughter won the $100,000 championship in the new SyFy Series, “Robot Combat League”! Their robot “Crash” is 7’9″ tall and weighs 828 lbs. For more info, see www.facebook.com/ShinselRobots
1/15/2013: Arduino support added
Also, removed external dependencies, so it’s easier to reuse the code posted here. For more info on Arduino support, see the Loki Electronics and Source Code Download pages.
Videos
Also, search for “Loki Robot” on YouTube
- Loki Watches Star Wars – A funny video I made of Loki watching is favorite move, and getting scared. I hope you enjoy it.
- Loki More Behaviors - This shows Loki doing some interaction, and showing off some of his newer behaviors.
- Loki Cleans Up – Video of Loki looking for objects on the floor and picking them up, using the Kinect sensor for 3D object detection.
- Loki Robot 1 - First video of Loki, when he just had one arm. Testing out his conversational AI.
- Loki Robot 2 – Exploring the House. This shows Loki’s navigational capabilities using his built-in map and A* navigation.
- Loki Robot 3 – New Arm and Object Recognition. Using OpenCV SURF for object detection, and showing off some Karate moves.
- Dancing Robot; Loki’s little brother- This is a RoboNova robot I built, and programmed rock out with “Domo Arigato, Mr. Roboto”
In the Design area, I have photos of the robots during construction, as well as schematics, software design overview, and the source code for Loki, Turtle, and Seeker. I hope you find this information helpful in your own designs.
it is amazing!
Hi!
You seem to have an eye on this with robots for “normal people”
My spark was lit when you saw StarWars & Battlestar Galactica in the 70s, and interest has only increased with the years when the films Terminator, I Robot, Judge Dreed, Transformers and Star Trek, etc. has passed the big screen.
I have long wanted to make me a robot that you can have some fun with at home.
But as time and money has always been an obstacle seems “your” solution interesting.
Was very inspired by your robots but especially when the robot Loki, I’ll try to start with a small project now
Thanks for a great inspirational site and your generosity to show your “solutions”!
Hope will confer with you if you “get stuck” if I get started?
Sincerely. Stefan, Borlänge in Sweden.
Dave,
I’m doing another article for Servo Magazine and am featuring Loki, again. This article is a bit different from the others in that I am describing how easy it is to find robot parts or steer your robot design towards the parts that you find. You’ve told me in the past, but, could you tell me again of all the unique things you used in the construction of Loki. E-mail me directly, if you don’t mind. Tom
Will do.
Dave,
In the LOKI mechanicals for the arm, specifically shoulder joint, you use a dc geared motor with encoder. This drives a chain and effects eventual rotation of the shoulder joint. I have built an arm similar to yours (still under contruction) except using a stepper motor and chain drive. Since the dc motor is not a servo, I was wondering how you command the dc motor to start/stop and go to the correct position? Of course I understand the feedback loop from the encoder, but doesnt this mean turning on/off the motor for a specific duration? Then, how do you calculate that duration?
Reply
The stepper motor sounds good. One thing is they can miss a step, so the encoder seems like a good idea to detect this, but you could just use sensor to detect home (that’s what printers do). Make sure you properly ramp up and ramp down the acceleration to avoid missed steps.
Send me a picture when you get it working!
Dave,
In the LOKI mechanicals for the arm, specifically shoulder joint, you use a dc geared motor with encoder. This drives a chain and effects eventual rotation of the shoulder joint. I have built an arm similar to yours (still under contruction) except using a stepper motor and chain drive. Since the dc motor is not a servo, I was wondering how you command the dc motor to start/stop and go to the correct position? Of course I understand the feedback loop from the encoder, but doesnt this mean turning on/off the motor for a specific duration? Then, how do you calculate that duration?
I am able to generate the necessary stepper pulses using a stamp connected to a stepper driver circuit. At least for now, it works during testing. I also plan to attach an encoder on the shoulder for position feedback.
Reply
The dc motor has an encoder on the back, which is connected to the motor controller. I use a Kerr controller that I got surplus, because it handles the PID for “Servo control” of a motor. All I have to do is tell the Kerr controller the position I want (in “ticks”), knowing that these get translated via the chain reduction to the arm itself. This is handled in these two functions:
CKerrControl::SetArmPosition()
CKerrControl::TenthDegreeToTicks()
Note that it all depends upon the “Home position”, which is calibrated at start-up by having each arm move forward, then move back until an IR sensor detects it. This is the home position for all future movements.
Dave,
Thanks for the info., which controller are you using from them. The Kerr Pic-step controller only provides 2 amps per phase. From my experimentation, I am looking at roughly 4 to 5 amps peak and running at perhaps 1 to 2 amps holding. I got this steppers new from surplus. They work well, but only this one provides the necessary torque. Also, you mentioned PID for servo control of a motor. What is PID and does that mean I use a dc motor as a servo???
Thanks for your information, I have always looked for this! I am a Machine engineer and have worked in this industry for two month. So there are some fields I don’t know about much and hope find more information on your website!
Dave (and daughter)
Watched the Robot Combat League last night. You guys did a great job and congrats on the win. Keep up the good work.
On another note, it seems as though the bots could use a better controller. If forward motion is controlled by one person and arms by another, it would take too much coordination. Why can’t one person do all the controlling? Why can’t the bots legs be controlled by a human like the arms?
Anyway, best of luck for the future battles…I’ll be watching
Thanks!
RE:”seems as though the bots could use a better controller. If forward motion is controlled by one person and arms by another, it would take too much coordination. Why can’t one person do all the controlling? Why can’t the bots legs be controlled by a human like the arms?”
Yes, controlling the legs was fairly difficult to master. There is a control for direction, another for leg height, another for leg speed. They all interact with each other, and there are some combinations that cause the robot so wobble or loose traction. Plus, it was hard for my daughter and I to hear each other over the crowd
But, that teamwork part also added an interesting element to the show. Keep watching, it gets even more fun!
You should make a Tutorial on how to make a robot like loki from scratch that will be the best
hey Dave i’m really impress with your fine work, you see i’m 19 years old and i would love to know how to code. do you know any books or sites that can teach me???
Great job on Loki! He’s so cool. How much did it cost for you to make loki?
There are so many variables; but roughly $3,000, including the laptop.
Hey Dave. You wouldn’t mind starting an online class in robotics so I can learn more could you? I’m 18 and I’m heading into the field of robotics. But I gotta know. who was the hardest robot to create: Crash or Loki?
I’d be glad to help get you pointed in the right direction; there is a lot of great info on the internet, and I can help point you to the information.
Mind emailing me some good websites? I’ll add them to my bookmarks and look at them. Bc I’m wanting to build Loki AND Crash a “sister”. wouldn’t that be nice?
Absolutely love Loki’s head, trying to replicate. For the life of me I cannot find any flashlight that is even close to what you used. It may seem trivial but it seems to e the only thing holding up the making of the head. Care to share where you got them?
Congrats on winning the Robot wars championship!
Chris
Hey i m trying to make a similar robot… but instead of windows i m trying to use linux and all coding to be done in java… what changes will have to be made… and how the vision system will be changed for that. plz share..
congratulation for winning the championship..
nice pic with chris Jericho