Output devices¶
This week, I want to make approximation feedback setup for my monowheel. When I’m riding on the road with it sometimes car could approach me from behind, and I may not even notice that. To check if I’m not blocking a way for any car I need to constantly turn my head and look back while on the road. The idea is mounting a tof sensor on the back of my wheel and attaching a vibration motor to my leg so, when the car approaches me I would feel the vibration with my leg.
To attach the motor to my leg I’ve made a test band with a silicone to test the material. If it will be strong enough, I’m thinking about molding vibration motor inside the band.
▼ Molding the legband
New boards¶
Starting with new boards I’ve made one specifically for tof sensor and one for general purpose where I break out every pin on a Attiny.
▣ SVG files:¶
boards-traces.svg
boards-outlines.svg
▼ New board
Here I wanted to attach sensor as SMD, but I missed that it has some components on the flip side, and they would prevent it sitting flat on the board so, I just used the connector.
Programming¶
I have used Arduino code from the Week 10 and simply added the LED to test my approximation setup board while my vibration motor is shipping
▼
▣ Arduino code¶
Testing¶
Adjusting the code from Week 10 was quite easy. In the resulting setup the LED is flashing rapidly when sensor is detecting object in the range from 2000 mm to 1600 mm and then lit up constantly while the “car” is approaching closer than 1600 mm.
▼ Testing the setup
As vibration motor arrived, I’ve started to testing it. The first motor was very weak, so I’ve tried the second one which occurred stronger but still not to the extent that I could rely on the road.
Honestly speaking I have no idea what is the purpose of all that components on the board. The motor itself should work just as it is with two wires.
▼ Testing the feedback strength
Trying to achieve stronger feedback I’ve unmounted the motor from the first breakout board and this actually made it vibrating much stronger so, I decided to mold just a motor inside the silicone band.
▼ Vibration motor detached
▼ Molding the band
▼ band-on
▼ band-on-on
▼ mono
▼ mono
Now you can see the setup in work. As I approach the obstacle and turn back the led is lit-up and the vibration motor is vibrating. As the obstacle is going out of the sensors’ range (1200 mm), feedback is stopped and the led doesn’t lit anymore.
▼ testing