Fully functional Bipedal social Robot. / General Chatting / Forums

Forums

4hv.org :: Forums :: General Chatting

« Previous topic | Next topic »

Fully functional Bipedal social Robot.

first previous 2 3 4 5 next

Move Thread

LAN_403

Hazmatt_(The Underdog)

Fri Oct 20 2017, 04:17PM

Registered Member #135 Joined: Sat Feb 11 2006, 12:06AM
Location: Anywhere is fine
Posts: 1735

You'd probably get better touch response from load cells or flexible resistors over switches. Switches are not going to give you much pressure feedback, and depending on what switch you use, grip may still be loose enough to drop an object.

Chris Cristini

Fri Oct 20 2017, 04:44PM

Registered Member #1749 Joined: Fri Oct 10 2008, 02:04AM
Location: Claremont New Hampshire
Posts: 497

Hazmatt_(The Underdog) wrote ...

You'd probably get better touch response from load cells or flexible resistors over switches. Switches are not going to give you much pressure feedback, and depending on what switch you use, grip may still be loose enough to drop an object.

You mean something like this?

that's far better than simple switches

I wonder if this robot had toes these can be used to help with upright walking? I believe we use feeling in are toes for walking

Conundrum

Sun Oct 22 2017, 06:35AM

Registered Member #96 Joined: Thu Feb 09 2006, 05:37PM
Location: CI, Earth
Posts: 4062

Just a note, make sure you have good quality connectors for it. I think phone cables use displacement connectors as this does not stress the wire much.
Also they can't take a lot of current (50mA IIRC)

Hazmatt_(The Underdog)

Sun Oct 22 2017, 04:32PM

Registered Member #135 Joined: Sat Feb 11 2006, 12:06AM
Location: Anywhere is fine
Posts: 1735

Yea a flexible resistor is perfect.

I don't see a tactile switch being adequate for grip because it will snap-over before you have enough pressure on say a can of soda, and the can will just slip out even with a hand closed.

Chris Cristini

Sun Oct 22 2017, 09:18PM

Registered Member #1749 Joined: Fri Oct 10 2008, 02:04AM
Location: Claremont New Hampshire
Posts: 497

Conundrum wrote ...

Just a note, make sure you have good quality connectors for it. I think phone cables use displacement connectors as this does not stress the wire much.
Also they can't take a lot of current (50mA IIRC)

Would direct solder joints instead of a Connector work well I have almost no experience with Phone cord.

Hazmatt_(The Underdog) wrote ...

Yea a flexible resistor is perfect.

I don't see a tactile switch being adequate for grip because it will snap-over before you have enough pressure on say a can of soda, and the can will just slip out even with a hand closed.

The whole switch idea was just a cheap way of some feed back But I did not think of a real world solution. Thank you!!! I would not have been able to figure out what I need to Do with out the help of this forum!! I wonder why I have ever used any other forum?

Does anyone have any Idea of how to make a good Kickstarter As you all know I have a hard time making a decent quality post

Here is a link to the preview

Kickstarter said it is not complete enough But I misunderstood they meant the campaign not the robot it self I have no clue how to make good videos or anything social for that mater. Another thing is most Kickstarter campaigns have a team of people and a fully functional prototype. This campaign will require a ton more to get any funding.

Chris Cristini

Thu Nov 09 2017, 05:51PM

Registered Member #1749 Joined: Fri Oct 10 2008, 02:04AM
Location: Claremont New Hampshire
Posts: 497

What are the chances of re purposing A CPU for ASIC? Well after more research on that I think we need an open source High performance solution over GPU. GPUs are so power hungry and for ASIC its to expensive eh I am disappointed at the market for AI solutions.

Chris Cristini

Sat Dec 02 2017, 05:36PM

Registered Member #1749 Joined: Fri Oct 10 2008, 02:04AM
Location: Claremont New Hampshire
Posts: 497

So on the subject of wires my new job is at Whitney Blake building wires and learning about the trade so I may ask if I can have scraps. They work with Litz, twisted pair and many other types and gauges I am going to soak up so much overtime to get this project going again still stuck on servo selection for arms.

Conundrum

Wed Jan 17 2018, 07:27AM

Registered Member #96 Joined: Thu Feb 09 2006, 05:37PM
Location: CI, Earth
Posts: 4062

Good luck!
If its any help I made some wire myself using the good old "DIY Litz" method.
For those not familiar with it you get 12 or more identical lengths of 30ga enameled wire and twist it under gentle tension with a slow rotation.
If done right the resulting flexible rope is highly durable and far superior to anything normally available.
The same method is used in a lot of headphone cables and requires thorough cleaning of each strand for a solid joint.

EDIT: Despite a minor setback I acquired several quite high end graphics cards.
Its possible to replace RAM on these if you are particularly skilled, but a side effect is the need for some sort of imaging system to identify quality of the resultant BGA joints.
Also relevant is that a lot of early ones were underclocked for heat reasons, this can be fixed trivially and with better cooling and replacement of the horrible thermal pads can be capable of 1/10 the performance of a Titan X at the cost of significantly shortening operational lifetime.

Chris Cristini

Sun Jan 28 2018, 10:21PM

Registered Member #1749 Joined: Fri Oct 10 2008, 02:04AM
Location: Claremont New Hampshire
Posts: 497

Ah I'm stuck on a big project working with 30ga 30-40 strand holy shit but 60-80 hrs a week takes all my time. I will be back on it soon.

Good luck with BGA :)

Conundrum

Tue Jan 30 2018, 07:00AM

Registered Member #96 Joined: Thu Feb 09 2006, 05:37PM
Location: CI, Earth
Posts: 4062

Yeah, its a steep learning curve but doable with the right kit.
Hint: if you are using BGA bigger than maybe 8 balls get the board made professionally. Not only will it avoid using dangerous chemicals but it can be tested before the chip(s) get fitted.
A good protoboard setup for short term use only is one with vias and tiny holes so the solder flows correctly.
Solder from the back one pin at a time and if you do it right the chip normally experiences far less stress than even a single conventional reflow cycle. I learned this tip while working with flaky graphics cards!
EDIT: Has some 63/37 balls here but they do need quite careful placing.
I believe that some early chips preplated the pads ONLY with 50um In so that the ball sticks initially, then reflow correctly melts it.
Core of the ball is different than the outside for a reason

first previous 2 3 4 5 next

Moderator(s): Chris Russell, Noelle, Alex, Tesladownunder, Dave Marshall, Dave Billington, Bjørn, Steve Conner, Wolfram, Kizmo, Mads Barnkob