The Hokuyo UTM-30LX Laser Rangefinder is a great choice for doing 2D slam with gmapping or similar solutions. It has excellent performance with a 40Hz scan rate, a working range of 0.1 to 30m and a 270° field of view.
If you are installing one on your robot it might be useful to know where the optical center is and where the transmit and receive optical axes are located. So, after having previously taken the Hokuyo UTM-30LX apart, we finally got around to working out some mechanical drawings. Keep in mind that the full cylindrical viewing region should be kept clear of occlusions for best performance.
If you need a CAD drawing, it is now available here in STEP format. (right click, save as, etc) The critical dimensions should be accurate, but there are some minor cosmetic details left out. Caveat emptor, as always when it comes to these things.
If you are looking for the Hokuyo URG-04LX Laser Rangefinder it is over here.
Authorization controls can be used to determine if the user is allowed to perform the requested task. This is more difficult to implement than simply asking for password but can be useful to prevent some types of problems. For example, it might be useful to provide your customers access to a tele-presence robot to tour your facility or attend meetings, but it you may want to restrict where a customer is authorized to operate the robot. If you owned a tele-presence robot, you could use authorization controls to prevent your mother-in-law from going into your messy bedroom or secret laboratory when she was using it to babysit you children.
The military may find these controls useful for UAVs by having trainees that can fly but may not have access to fire control or have throttle limits placed on their operation. More complex authorization controls will be useful as applications move from purely military to more public safety applications. There will need to be ways to restrict operators from operating equipment outside of their responsibilities, or capabilities.
There seem to be a few interesting categories where this could be useful for preventing abuse and improving safety for mobile robotics. Location based restrictions on operations could limit UAV purchased by a county police department to operation within the counties borders and at restricted altitude limits without administrative override. This could make UAVs much less useful in the event that they are stolen. Time based restrictions could be connected to an organization's time clock so that off-duty public safety officers would not be tempted to use the equipment for personal gain. Functionality based restrictions would be useful for preventing accidents by operators-in-training and may be useful for medical robots to control the dispensing of restricted medications.
Implementation of authorization systems will be challenging. Management of location based per user keep-out zones may create administrative issues and may be difficult to configure. Robots that use probabilistic based systems for determining their location may have issues when a robot sudden finds itself probably inside a restricted area. Can they leave or are they stuck there until someone intervenes? This is going to be difficult to do correctly.
An authorization control system can improve the safety and security of mobile robots, but it will probably be the most difficult part of robot security to implement in a way that it does what the users expect of it. Even a simple system could prove challenging to implement.
Authentication is the process of determining if the user is who they say they are. It is the first line of defense and the absolute minimum requirement for a secure system.
A proper authentication system requires that each user has a separate userid. This requirement is to ensure that operators understand that they are personally responsible for the use of the equipment. Production systems should have operator accounts which are separate from maintenance and administrative accounts to prevent tampering with system logs. Research systems will obviously have different requirements but separate accounts can still be implemented with judicious use of sudo.
Some might make the excuse that passwords will get in the way of field operations, however systems such as fingerprint readers and cellphone key-lock style pin entry provide examples of how users can be authenticated quickly. While it may not provide the most robust security it will help enable logging and may help prevent casual system abuses. While managing multiple accounts may be beyond the capabilities of some embedded robotic systems, even the smallest networked robot deserves a password.
The first easy solution for better robot security is to stop shipping robots with a default password. Users should be forced to choose a unique password upon startup, just like when you setup your WiFi access point, because we learned what happened when Linksys set a default password for all of it's WiFi routers. If your robot has a default password please change it before you find it has left you. Providing a system for multiple users to operate the robot should not be much harder and will greatly improve security with minimal additional engineering costs.
Sometimes I wonder if all commercial robots ship with a default password. I wonder if I'll wake up one day and find out that someone has stolen one of the military's hunter-killer drones out of the air because it had a user name of 'atomics' and the password was 'atomics'.
Ok so you are still not convinced that you need to get rid out default passwords, so let me tell you a true story of robots and default passwords. I'll leave out the names of the guilty for entertainment value as you will see this could have been anyone.
Once I was watching a representative from a robotics company, whose robot you have probably seen on YouTube, give a talk about their robot and how it was useful and why you should buy one. When the presenter got to the slide that describes how you can connect to the robot using WiFi, the person sitting next to me opens their laptop and attempts to connect to it. It asks them for a user name and password which they obviously don't have, so they download the robot's user manual and lookup the default password. They are now logged into the robot that is on the stage in front of the entire audience while the presenter is completely unaware that the robot is no longer under their control. While at the time I suggested that it would be impolite to interrupt the presentation, I am now convinced that it would be an embarrassing but relatively harmless learning experience for the industry.
So in conclusion, robots should not have a default password. A unique administrative password should be set during initial configuration. At the very least you may want to change the default password before you give your next presentation, and certainly before the next CES.
Robo-ethics is important and we can spend time debating the merits of hardcoding Asimov's Laws into every positronic brain, but I believe these issues can wait until the singularity is a little closer. What we need to worry about right now the ethical use of teleoperated robots. Researchers and manufacturers have an ethical responsibility to provide robots that are secure and encourage good security practices on the part of their customers.
Just like your desktop computer, we need security for robots and this needs to happen now, not later.
It is clear from these events that with the growth of mobile robotics and commercial UAVs the robotics field will be faced with security issues that could pose a serious setback to the future of the industry, however there are practical low cost incremental changes that can improve security and help minimize the damage of the inevitable incidents.
If someone is injured or killed by a robot it could be:
An unavoidable accident
Negligence on the part of the manufacturer
Intentionally caused by an authorized user
"Hackers"
Tele-operation for all it's possibilities can be a dangerous thing.
The primary goal of robot security should be to prevent accidents, injury and deaths. When that isn't possible data should be logged so that the guilty parties can be identified and charged in civil or criminal courts.
Since the early days of the Internet we have learned some painful lessons. We have learned that actual security, as opposed to security theater and security through obscurity, can be divided into three main areas, authentication, authorization and accounting. These topics will be covered in the following parts.
Patrick Bouffard from the Hybrid Systems Lab at UC Berkeley has done a great job documenting the ROS 3D Contest entry shown below. So it should be easy to reproduce the results if you are lucky enough to have access to a Kinect and an AscTec Pelican quadrotor.
If you already have an Ascending Technologies Pelican or Hummingbird quadrotor you may be interested in this wiki and this mailing list, both of which seem to have useful information for researchers working with this specific hardware.
Also, Ascending Technologies is offering a 15,000 Euro sponsorship for a team doing UAV research. Proposals due by February 13th.
In unrelated news, robotics graduate students with human companions will probably be excited to hear that the paper deadline for IROS 2011 appears to have been moved from February 15th (Seriously.) to March 14th.
All new official I Heart Robotics merchandise for 2011 is now available. The T-Shirts are currently on sale for $12.95 and feature stylish Glow-in-the-dark technology.
CSIRO has been using ROS with it's autonomous Bobcat skid steer loader that it uses for cleaning up around the lab. There are obvious applications for robo-mining in Australia as it is one of the largest industries and there are serious safety concerns due to the obvious dangers involved in mining and also some of the best mineral deposits are in areas infested with drop bears. These kind of heavy robots and co-operative autonomous control also seem usable for robo-farming.
On January 26th, Patrick Goebel will present his Pi Robot at the Homebrew Robotics Club in Mountain View, CA. There will also be other ROS related presentations. More info here.
Another day, another ROS Repository. This one is from the Autonomous Systems Lab at CSIRO.
Garratt Gallagher, whose work we have featured previously, is working on a Kickstarter for his Bilibot project. Funding closes on Jan 19 at 10:06am.
Once again, it's shameless self promotion Sunday and this week I Heart Engineering has a fine assortment of new tools in stock.
The NZ-03 Chip Cutter, it is designed for removing surface mount resistors and capacitors. The grip is ESD safe and is made from an ergonomic and environmentally friendly thermoplastic elastomer. It also has a hole designed into the handle for attaching a strap.
The jaws have an adjustable opening angle and are made from S58C steel.
The NZ-03 cuts vertically for ease of use in high density circuit boards.
The tool cleanly removes the damaged chip quickly and easily without damaging the pads.
The NZ-03 Chip Cutter is great for repair work removing surface mount capacitors and resistors. It can also be used to cut IC leads in dense layouts. On sale all this week for $32.95 at the store.
Here you can see the PA-90 strip gauge attached to a pair of PA-14 wire strippers.
The gauge is easy to install and the adjustable position is set by means of the thumb screw.
The PA-90 strip gauge can help strip wires to consistent lengths as short as 1mm. Free while supplies last with the purchase of PA-14 wire strippers that are now on sale for $37.95. The PA-14 wire strippers can strip some of the smallest gauge wires, including 32AWG solid and 34AWG stranded wire. For reference these gauges are thinner than standard wirewrap wire.
I got these for myself, but there are more In Stock if you need them.
The NP-05 Plastic Nippers are specifically designed to cleanly remove a variety of gates from injection molded parts. Great for trimming prototypes, building model robots or assembling injection molded injection molding machines. The nippers are 120mm long and the tapered head is 11m wide when closed. The slender design provides ease of use in restricted areas. They can also be used as light-duty wire cutters able to cut copper wire up to 1mm in diameter. Available all this week for $19.95.
More great work from Quentin Lindsey, Daniel Mellinger, and Vijay Kumar from the GRASP Lab at the University of Pennsylvania. They now have their quadrotor helicopters working in teams and building modular towers. This is from the same lab that built the acrobatic quadrotor capable of aggressive maneuvers.
Normally we aren't big fans of the 'top ____ of ____' type posts but the IEEE Spectrum Automaton Blog has actually found the best of the best from CES. Behold.
This robot represents a revolution in consumer robotics, a robot that not only balances on you but it also gives "a delightful sense of bodily pleasure". While some YouTubers (sp?) are doubtful saying, "I don't know - it doesn't seem to do anything that a bag of spiders couldn't". I believe that the future will show the success of this robot and it's awesome soundtrack. It will be interesting to see if it comes with an API or wireless interface.
More of the best robots of CES can be found here and while you are at the Automaton blog, don't forget to check their Top 20 Robot Videos of 2010.
Like the robots that replaced factory workers, the PR2 may be working towards replacing professors.* There is a list of graduate and undergraduate courses being taught with ROS and/or PR2s here. Soon the PR2s may be teaching the classes themselves. If your school doesn't yet have a PR2, you can order one here. However, I don't think you get to pick which professor it replaces.
The PA-01 Combination Wire Pliers are a bit of a jack of all trades and can be used as wire cutters, wire strippers, crimpers, and screw/bolt cutters. It strips wire from 28AWG to 14AWG and can cut metric screws of various sizes (M2/M2.6/M3/M4/M5). There are separate dies for crimping open barrel, bare and insulated terminals.
This video shows the pliers in action. They are available here from the I Heart Engineering store.
According to this, "The price for Primesense development kit is $200 excluded tax and shipment fees." You can apply to purchase the PSDK hardware here.
This year, the various intractable labor issues combined with recent advances in robotics should create an opportunity for more robot farmers. Unlike some of the other business models we have seen recently, farming robots should be a relatively high margin business and should also enable significant cost savings on the part of farm owners. When the robots aren't tending crops they could also be used as scarecrows to fend off pests.
Another day, another great ROS package. Today's package is avr_bridge from Adam Stambler and Phillip Quiza at Rutgers University.
avr_bridge helps simplify connecting AVR microcontrollers and Arduinos to ROS by automatically generating C++ interface code so you don't have to worry about writing yet another serial driver.
The team at Rutgers is currently using it with their PIPER robot and their IGVC entry.
This is better than the previous design but the pulley is just too small.
Here is an idea for preventing damage to the wire. Doesn't function as intended with wire rope stop sleeves.
This sort of works, but requires a constant tension to keep from unspooling. Testing and/or mathematics will be needed to determine if attaching a pulley to a servo is beyond the mechanical limits of the output shaft.
The idle pulley design works well, but bearings with a 3mm bore are way too expensive. The next design will test bronze or teflon bushings for the idler.
Here a stop sleeve that is one size too large has been ruthlessly swaged on to the wire rope. Perhaps epoxy might be a better method for seizing the end of a wire rope that is 3/64".
Unfortunately, it looks like 3/64" wire rope is still too stiff to be wound on a 38mm (1.5") pulley. It does not lay flat on the pulley and has a tendency to unspool. Braided fishing line looks like an alternative.
It looks like wire rope won't work for the original concept, perhaps it will work on a 76mm (3") pulley. Testing with this design showed that the wire would come off after the first layer due to a design flaw.
This looks like it might work better.
However, there are still problems with the initial lay of the cable. While it may not be a problem for limited cycles, fatigue at the starting hole will likely be a problem.
This looks like the source of the problems.
So, here is another fine assortment of design failures on the road to success and robots with tentacles.
OMPL looks like it will be useful for piano movers, robots and robotic piano movers. ROS integration in the near future will be useful and hopefully will enable integration of voxel grids and OctoMap into the motion planning system so it can use live data from 3D sensors.
As more of the components required for 3D robotics are being developed and released as open-source software, it will be interesting to see if the hardware keeps up or if we end up waiting for Moore's law to enable real-time functionality.