Hello backers, please see our link below. We have relaunched the Logitraxx for another try. We've made some base changes to the design to reduce the cost in attempt to better our chances for a successful campaign. Enjoy!
We were trying to get this completed before the Kickstarter ended, but didn't finish in time. We decided to post it anyway just to help a potential relaunch should that happen. We are looking at what changes need to be made from just cost reducing the whole thing to changing some of the dynamics of how it could be more appealing as a robot kit to a larger audience. We've learned a lot just running this campaign and the results are being studied closely.
The video above shows the Snow Cat Explorer operating with two Parallax Sonic Range Finders. Each one is pulsed and read simultaneously and independently of each other. the Snow Cat employs a full "auto-pilot" FSM (Finite State Machine) where as the previous units merely used some obstacle avoidance logic to get around. The latest rev of our firmware is actually making decisions based on its sensory input to determine both speed and direction in a more planned method rather than simply being reactionary in operation as previously.
The interesting thing here is that the Auto Pilot does not need to "poll" the sensors. The sensors are polled by separate logic algorithms autonomously, constantly updating the status registers of the Auto Pilot FSM about 52 times per second. That is as fast as the Parallax sonic sensors can operate. The FPGA of course could operate much faster. In fact, I had to add delay timers to slow things down a bit so that the servo had time to move to its commanded location. Just in the time it takes the servo to rotate could result in more than a dozen distance updates along its rotation axis. The only I/O the Auto Pilot is currently controlling directly right now is the servo on top (directing where to look) and the DC motor drive circuit. All other I/O and peripherals are handled separately in the FPGA. This completely off-loads house keeping chores to other state-machines while keeping the Auto Pilot on task and unencumbered doing just one thing, "driving the vehicle".
We are just running out of time demonstrating what you can do with it in an effort to raise interest. We may rethink the project and retry it again later in the year. If you have any suggestions now would be a great time for feedback. Thanks!
We have updated our main video with a little more of our body top features which now includes our Half Track, which is nearly complete but not quite ready to run around on its own yet. The front wheels are Lego wheels. We love these wheels but apparently this wheel only comes as part of a Lego kit. So, we'll have to select a new set of wheels by production time.
The Half Track is coming along nicely. The wiring is mostly done, steering servo is in place and operating, but no steering gear is connected up yet. I have an older generation 3D printer and this is about as good as she can do (at least with my tuning skills). The world of 3D printers is growing rapidly and hardware vendors continue to improve on the quality of their next gen printers. 3D printers are really changing the dynamics of what constitutes product production and what the supply chain of the future will look like for consumer products. That's why we made the Logitraxx support different mounting configurations so that you could really be inventive about what you do with it.
We have a third vehicle in design now that we call the "Snow Cat Explorer". It will utilize both IR and Sonic for driving. It think its going to be my favorite :~)