Picture Pages (back to main page)
1 2 3 4 5 6 7 8
I haven't taken picture for a while, because most of the work was one minor adjustments. Here are some new components since the last pictures.
This is the main power distribution board. It takes the power from one of the two batteries and routes it to the Regulator board and the 167 evaluation board, which has its own power regulation. The tape (by the tie wrap in between the switch and board) hold an NMOS FET which is on the ground line. It provides reverse polarity protection. The left battery bay (Left picture) holds the battery that directly supplies the H-Bridge. The right one (right picture) contains the main power battery.
One top of the Evaluation board is the mouse interface board (left) and the bump switch and shaft encoder interface board. I was going to place them beneath the evaluation board but I ran out of room.
These two pictures show some of the shaft encoders. The IDC header next to the gears in the connection between the above shaft interface board and the one next to the shaft encoder. The IR detector/emitter pair themselves are covered in black electrical tape.
After experimenting with running the robot, I realized that the H-Bridge drivers get hot. To combat this, I placed a big heat sink on the board. Also I put a 5 volt fan above the heat sink. On the heat sink there is an analog temperature chip. Software monitors the temperature is turns on the fan. When the temperature gets really got, the software shuts off the motors and turns on the buzzer as a warning. This is not entirely necessary because the H-Bridge chips have a status out, and they shut down automatically under high temperature.