ElEscalador
Posts: 681
Joined: Tue Dec 15, 2015 4:55 pm
Location: Detroit, MI USA
Contact: Website

Would you use this transistor to replace this one??

Sat Jan 23, 2016 2:04 am

I think my roombaRPIbot has a bad bridge transistor - one of the wheels only goes in reverse. The one that's in question is a D882 (http://pdf1.alldatasheet.com/datasheet- ... /D882.html). I have a donor vacuum robot of a different brand and it has some BD441s (https://www.fairchildsemi.com/datasheets/BD/BD441.pdf) that look kinda close to me?? But I don't really remember what all that stuff on the datasheets means and whats important. I'm sure it'll make it go again (assuming I've found the problem to begin with), but will it make the wheel in question spin at a way different rate than the other wheel? Sure - I could order the exact part but I want to play with my robot this weekend! (eager to start work on the navigation software). They're both NPN with a 5V Vebo and 1a of base current. Beyond that the details are in a foreign language to me.
My Autonomous Robot Project and a few of my other projects below.

https://lloydbrombach.wordpress.com/

Adrianfu
Posts: 45
Joined: Tue Dec 01, 2015 7:13 am
Location: Yarraman Australia

Re: Would you use this transistor to replace this one??

Sat Jan 23, 2016 2:51 am

Looks good to me.

Adrian

W. H. Heydt
Posts: 10998
Joined: Fri Mar 09, 2012 7:36 pm
Location: Vallejo, CA (US)

Re: Would you use this transistor to replace this one??

Sat Jan 23, 2016 3:20 am

Ummm...got a write up and pictures of your Roomba RPi bot? What is it capable of? (A Roomba is pretty capable to start with...)

ElEscalador
Posts: 681
Joined: Tue Dec 15, 2015 4:55 pm
Location: Detroit, MI USA
Contact: Website

Re: Would you use this transistor to replace this one??

Sat Jan 23, 2016 2:17 pm

Thanks, I'll give it a shot.

No write-up yet. Just started tinkering with the rpi a month ago and decided to use it/this project to learn C++. So far I've got it polling sensors, basic drive program and odometry program, and reading me the battery level in morse code when it reaches 50 and 20%. And it still vacuums. The goal is for it to be able to map any new environment by itself so it the navigate intelligently. Find and come to me on verbal on command and be a mobile media player, home automation controller, start my car in the cold mornings and check through OBD2 data for warnings. Maybe add a manipulator arm to fetch a beer and light a candle when I have lady over.

Anyway, teaching it to map it's environment is next - right after adding a 2nd level of bumper to protect the rpi and code so it slows down when it's ir sensors see an obstacle so it bumps more softly. (like it does when roomba is in control). Maybe an ultrasonic or laser rangefinder to so it can map some things without having to get with 10cm of them. I suppose I should take a break and take some pics and videos and do a write up when I get it moving again.
My Autonomous Robot Project and a few of my other projects below.

https://lloydbrombach.wordpress.com/

Return to “General discussion”