Thursday, June 13, 2013

How much power is there in PowerCube?

How much power does a PowerCube produce? There are several versions of PowerCube, with various engines. For example, my unfinished PowerCube IV will have a Briggs and Stratton 37 horse engine. When I'm done I have no idea how much power it will generate. I don't know what sorts of load it will be able to move, or how fast it will be able to move them.

Videos of LifeTrac are impressive, but I'm an engineer. What will it be able to do? How will I know if my PowerCube is subpar or by some fluke perfect? I belive that PowerCube VI is under development, but can't tell you if the new designs are more powerful than the old ones. (I also can't speak to reliability but that's another story.) If OSE is going to rapidly iterate on its designs then it needs to know when an iteration is better.

I understand that Tom is putting a bigger engine into version VI. How much better will it be? What is success?

OSE needs a simple fixture to measure hydraulic power output under various conditions. I'd suggest the initial design allow the independant control of at least two variables: load, and fluid capacity. I'm not sure what it would need to measure, but suspect that measuring pressure drop over the load could stand in for power manifested. A more complete design would also measure absolute pressures, and flow rate.

Here is a possible implementation. A non-load bearing cylinder (the kind that stores fluid when expanding) in parallel with a needle valve. A pressure valve before and after the needle valve. Expanding the cylinder would decrease the level of the hydraulic tank. Tightening the needle valve would simulate a load.

As a complete novice in hydraulic design, I'm sure the above is wrong. However the concept holds. We can measure any PowerCube with such a fixture and can definitively show progress (or its absence). Finally, such a fixture may be very useful in diagnosing failure modes in the PowerCube (such as stalling.)

I'd love to see some data on what the earlier PowerCubes can do and how they measure up to the new ones!

Thursday, February 21, 2013

Perhaps the glut of STEM workers is fueling the open source economy?

America has too many Science, Technology, Engineering, and Math experts. There aren't enough jobs for our high tech graduates. You may not think so, but the story is coming out. Perhaps having a lot of highly trained, unemployed people isn't all bad though. There are a number of great movements that rely on voluntary donation of technical work. Opensource Ecology is only one of many.

These projects wouldn't be going anywhere if they didn't have people with the time and energy to work on them. I suspect that a lot of the work is coming from STEM workers who are under employed. This would be somewhat ironic. The story that there aren't enough STEM workers appears to be intentionally woven by large employers in order to depress labor costs. If that's so, then what a surprise to find competing products on the market made by the workforce they've tricked.