Using BELT_02 code I managed to get all four sensors and motors to work, as I realised my error with my initial attempt (failing to map all values of distance and power).

There are 4 sensor and motor combinations/groups, I labeled them FL, BL, FR, BR. [F = front; B = back; L = left; R = right]. The coupling/mapping was direct – vibration was coming from the point of distance detection.

Initially FR was only sensing and vibrating, after the code review and update all 4 groups were sensing and vibrating. However, only the BR motor kept vibrating the most and consistently. I also noticed a considerable delay when each sensor was activated.

The vibration strength varied based on the shroud’s effectiveness – the shrouds were made from straws with the motors inserted into them, this is low cost and fast way to allow the asymmetrical weight rotate. In effect the shrouds were failing and not allowing the motors to rotate, thus preventing any form of vibration. 

The code and potentially the wiring needs further debugging. I’m using jumper cables left right and centre! which is fine for a quick and dirty prototype but very messy when trying to debug. If time allows, a revisiting of the code and custom connectors/lengths of wire to make it work better and neater. 

I will revisit the Project HALO code from Instructables and see what I can do with that, I believe it deals with the sensing and motors in more of a clock fashion. Power seems to be another issue I’m facing. So far I’ve connected a battery directly to the Arduino Mega 2560, but Project HALO advises this: 

“a 5v regulator is connected to the 9v terminals and this is sent to drive the Darlington IC (and in turn, the motors) so we have 2 power systems and the Arduino is isolated”

 

Parts list:

• Arduino Mega 2560
• 3v Vibration Motors: 256382 from Jameco.com
• HC-SR04 Ping Sensors
• Bread board
• Development Shield for Arduino Mega
• Custom 4-to-3 connectors
• Zip-ties
• Electrical/Duct tape
• Velcro Tape
• Male-to-Female, Female-to-Female, Male-to-Male jumpers 
• Old belt

 

More to come…