Slope test – Sentach

Took the headtracker out as I wasn’t expecting much lift today. At best 25kts (12.8m/s) at Pat Moreton. Flew perfectly, but the glide slope was not enough to keep altitude. 763g. Still waiting on props to arrive. ‘Tas heaps of drag points which could be eliminated. Could make a larger wingspan for these wind speeds.

Would be interesting to see what CFD says and how it compares to reality.

Time to have a crack at flight stabilization

Would like to get flight stabilization happening so it’s easier to fly FPV with the head tracker initially. At least if I balls it up I can throttle off, let go of the sticks and it will have some chance of landing flat. Would also be able to see compass headings, altitude and battery on screen through the OSD.

Think I’ll start here first and see if it works with that F3 board.

Some others to look at:

http://www.librepilot.org/site/index.html

Ardupilot

Betaflight

MWPTools for navigation to mix with the flight controller. That or the INAV software.

 

 

Sentach powered up

Put the motor in and re-balanced it. Flew at around 14:00ish under power with about a 30kt NNE (15.43m/s) for backup glideability. Flew so well. Only hit about half throttle with a 4s. Had heaps of lift, so I’d say I could max out at about 1kg payload with more throttle. Now onto a flight controller before sticking the head tracker in.

Flight weight – 1414g

New COG –  280mm from the L.E.

Sentach glider version

The Sentach glider worked well today at the Pat Moreton park in about 15-20kts NNE. Videos to be posted shortly.

Flight weight 680g.

COG 310mm from the L.E.

Beautifully smooth flat landings. Some wobbles as expected. The’s alot of drag points. Especially with the flat sides of the nose. Don’t think anhedral would totally fix it because of the nose as it’s obvioualy turbulating when a crosswind happens.

Crashes it once and the wing popped off nicely dispursing the impact force. Plugged it back together and went again.

The angled wingtips wouldn’t stop the tip vortex as XFLR5 shows in the sim.s. would be better to round into them like Gemot. The difference they made to Gemot was nothing short of impressive. Holding Gemots wing in one hand whilst spinning around, with and without wingtips gives a tactile feeling of the drag differnce involved.

More to come soon.

EAP’s – Electro Active Polymers

An EAP is a manufactured muscle fibre. If anyone knows where to buy, or how to make them., please contact me.

Preferably with contraction times measured in milliseconds.

I found some info here:

https://ndeaa.jpl.nasa.gov/nasa-nde/lommas/eap/EAP-material-n-products.htm

parker.com

https://ndeaa.jpl.nasa.gov/nasa-nde/lommas/eap/EAP-web.htm

http://www.hizook.com/blog/2009/12/28/electroactive-polymers-eap-artificial-muscles-epam-robot-applications

www.ct-systems.ch

Making EAP’s

https://ndeaa.jpl.nasa.gov/nasa-nde/lommas/eap/IPMC_PrepProcedure.htm