Jim,
I have a few questions…
What is the OD of the end foot cap?
What is the lengh of the straight portion of the foot pad, from the end to the beginning of the curve?
The AT-01 is 0.5" OD, correct?
I won’t go where your idea of the tips from latex gloves took me 
dj
OD 0.437"
L 0.375"
Correct…
Update: All parts for prototype are on order, waiting for them to arrive. 8) I have a very good feeling about this one.
Here is an update… And it’s a good one!
I’ve received all of the parts. I’ve built up one and it’s working wonderfully. The throw required to actuate the switch is minimal. The pressure required with one of the stronger springs is only 3 ounces. I will experiment with the weaker springs as well. I suspect there is a lower limit for this to provide reliable movement. The thing is strong as ever. Here are some images of what it looks like so far.
Great work Jim! 8)
The parts look great and it look very solid when assembled.
Did you need to add some sort of lubrication when mounting the inner parts?
I just tested it with the Atom Pro. It’s perfect. The only problem I have found is it’s not easy to cut the rubber end caps down to length. This is a relatively minor issue though. The customer will have to do it. I just need to find a method that is easy to follow and reproduce decent results. Of course I’m open for ideas…
Oops forgot to answer the lube question. The parts are moving freely without the need to add lubrication.
By placing a piece of cardboard between the pad and hub when assembling the parts, I’ve got the throw down to 0.013" LOL 8)
Looks so simple on the outside and it also looks solid as a rock. I don’t think it needs any lube since plastic inserts are used, but if you find that some lube would improve the performance, you might want to try Super Lube with teflon. My Sherline Mill uses this synthetic grease and it works really well. It’s a light weight grease that almost turns to oil when worked in a bit but it wont run.
Did you have the plastic inserts machined to specs?
Now watch, Crust Crawler will try to copy it… 
Hi Jim,
Nice design! Can you tell anything about the working angle of the sensor? It doesn’t have to be as big as the sensors used on the hybrid since the T-hex has a extra DOF to keep the sensor in a 90 deg angle to the ground.
I saw some posts about using analog signals instead of digital ones. I prefere digital ones since it is easier and quicker to read and doesn’t give extra information.
I think you should have both Hybrid and those ground contact sensors in the shop Jim. The Hybrid version works great as well!
As always, great work!
Xan
They are standard off the shelf parts. 
Hi Xan, thanks! It will work reliably as low as 35°. 8) The biggest problem with the Hybrid version is it’s laser intensive. I’m much more interested in receiving a box of parts for 1000 legs, than babysitting the laser for hours on end. I do want to find a way to incorporate the 1/2" tube into the hybrid style tibia. That’s the next step.
Hi Jim,
Great work with the assembly guide!
What is the length of the tube you used on this picture?
Is it a 1,5" tube? (It sure looks like though… 
)
I know the shortest tube you are selling are the 1,5", but if someone choosed to cut down the tube, in how short tube would the switch fit?
I will second (or is that third or forth) it that they look great. My assumption is as well that they will work in digital mode. In that way we could choose to try to hook these up to be interrupt driven or we could poll them if we so choose.
Again Great Work!!!
Looks like you are having fun
Kurt
Thanks for the visualisation Jim!
I belive it should be possible to make it a bit shorter, but maybe not necessary though. Looking foward to test it out one day.
Yeah I made it as small as I felt comfortable with. lol I have a package going your way very soon. Trying to figure the best method to ship and avoid some of the problems from before.
So are all the bits and pieces available? I bought some aluminum tubing, I was going to make up some custom (shorter) legs for my 'quad. These sensor legs (feet) could work.
Alan KM6VV
I’m holding on some 1/8" 4-40 socket head cap screws and some miniature 4-40 nuts before we can sell them. Not dragging my feet, just waiting… 
im very interested in buy some of these too. its good to know they fit the 1.5 tubes. looks like the wire will fit nicely though the hub08. is there any code on these yet. iv been looking about and so far i have this for a quad:
Variable
[code]
RF_FSR var bit
RR_FSR var bit
LF_FSR var bit
LR_FSR var bit
prev_RF_FSR var bit
prev_RR_FSR var bit
prev_LF_FSR var bit
prev_LR_FSR var bit
RF_FSR_PosY var sword
RR_FSR_PosY var sword
LF_FSR_PosY var sword
LR_FSR_PosY var sword
FSROn var bit[/code]
In main
[code] ;Terrain adaption
IF FSROn THEN
gosub ReadFSR
ELSE
RF_FSR_PosY=0
RR_FSR_PosY=0
LF_FSR_PosY=0
LR_FSR_PosY=0
ENDIF
;Balance calculations
TotalTransX = 0 'reset values used for calculation of balance
TotalTransZ = 0
TotalTransY = 0
TotalXBal = 0
TotalYBal = 0
TotalZBal = 0
IF (BalanceMode>0) THEN
gosub BalCalcOneLeg -RFPosX+RFGaitPosX, RFPosZ+RFGaitPosZ, (RFPosY-cRFPosY)+RFGaitPosY+RF_FSR_PosY, RFOffsetX, RFOffsetZ]
gosub BalCalcOneLeg -RRPosX+RRGaitPosX, RRPosZ+RRGaitPosZ, (RRPosY-cRRPosY)+RRGaitPosY+RR_FSR_PosY, RROffsetX, RROffsetZ]
gosub BalCalcOneLeg [LFPosX+LFGaitPosX, LFPosZ+LFGaitPosZ, (LFPosY-cLFPosY)+LFGaitPosY+LF_FSR_PosY, LFOffsetX, LFOffsetZ]
gosub BalCalcOneLeg [LRPosX+LRGaitPosX, LRPosZ+LRGaitPosZ, (LRPosY-cLRPosY)+LRGaitPosY+LR_FSR_PosY, LROffsetX, LROffsetZ]
gosub BalanceBody
ENDIF[/code]
Endsub
[code];[ReadFSR] Reading input from Tars pressure sensors
ReadFSR:
input P0
input P1
input P2
input P3
prev_RF_FSR = RF_FSR
prev_RR_FSR = RR_FSR
prev_LF_FSR = LF_FSR
prev_LR_FSR = LR_FSR
RF_FSR = IN0
RR_FSR = IN1
LR_FSR = IN2
LF_FSR = IN3
IF RF_FSR=0 THEN
RF_FSR_PosY = (RF_FSR_PosY+1)max 60
ENDIF
IF RR_FSR=0 THEN
RR_FSR_PosY = (RR_FSR_PosY+1)max 60
ENDIF
IF LF_FSR=0 THEN
LF_FSR_PosY = (LF_FSR_PosY+1)max 60
ENDIF
IF LR_FSR=0 THEN
LR_FSR_PosY = (LR_FSR_PosY+1)max 60
ENDIF
IF (RF_FSR+RR_FSR+LF_FSR+LR_FSR)>=6 THEN
RF_FSR_PosY = (RF_FSR_PosY-1)min 0[/code]
Well I’m sure there will be lots of leg switch code threads when the time comes. This thread is probably not the place for it though.
Oops. ill save it till then.
sorry jim. remove it if you wish.
