|Basic Underwater Robot Workshop 2016
Workshop Check-list and instructions
Please check that you have the following components in your group (There may some small variations in description).
Mechanical components Electrical components
16 mm pipe+ 2 m Pump motor with propeller 3 pcs
16 mm pipe T joint 8 pcs Speaker cable 16 m approx
16 mm pipe L joint 10 pcs Connecting wire 0.5 m approx
4mm 30mm screw for U-clamp 6 pcs Control box 1 pc
4mm nut for U clamp 6 pcs DPDT switches 3 pcs
Pipe clamp U 3 pcs Fuse 3 A 250 V 3 pcs
Cable ties as required Fuse holder 3 pcs
PVC glue 1 tin Cable screw connector 2 pcs
Heat shrink as required Eyelet crimp terminals 20 pcs
7 mm dia foam 30 cm Inline crimp connectors 20 pcs
4 mm banana plug red 1 pc
4 mm banana plug black 1 pc
+ May be in more than one length or different diameter.
Actions you must do
a) Split into two groups. One will build the frame, the other the electrical system.
i) Cut the 16 mm pipe into the following lengths:
2 x 23.0 cm
4 x 19.5 cm
2 x 11.0 cm
2 x 10.5 cm
2 x 10.0cm
2 x 7.0 cm
2 x 6.5 cm
6 x 3.0 cm
Ii ) Construct the frame as shown, following the design of the prototype frame, as follows:
a) Build the two side frames as shown below:
joints T joints
Use the 3 cm long pipe to join the T and L connectors so they butt closely. Now join the two side frames with the four 19.5 cm pipes. Look at the prototype frame if confused!
b) Drill two 4mm holes in the pipes to support the motor U clamps. Make sure the motor is a tight fit when it is clamped to the frame. Tidy up the motor wires using cable ties.
i) Cut the speaker wire into the following lengths. Please do in the order below (in some workshops the wire may already be cut):
First: 1 m 1 pc (from long wire) – for battery
Second: Approx 4 m 3 pcs (cut remaining long wire into 3 equal parts) – for umbilical
Smaller lengths of wire to connect the switch box as necessary – as required
ii) Wire the control box as shown in the attached diagram; use crimp terminals to connect to the switches, and join wires with crimp connectors or screw connectors. Check that the crimp connections are good by giving them a strong pull. If they part, redo. Make sure the fuse is inside the fuse holder! Note that the switch holes are inline, not offset as shown. Vertical should be in the middle. Do not close the box yet.
iii) Place 4 cm long pieces of heat shrink over the motor wires. Join the umbilical to the motor wires using inline crimp connectors. Test the electrical connections using a power supply. Keep fingers clear of propellers. If it does not work check your wiring.
iv) If all the electrical connections are OK, screw the lid on the control box. Slide heat shrink over connectors and shrink with heat gun (mind fingers!). Use cable ties to tie the motor cables to the frame and also at 25 cm intervals along the umbilical.
i) Test the ROV in the water and adjust the buoyancy cutting or adding more float material – you will need approx.. 14 cm per side, and it will need to be moved around to give horizontal stability, and glued in place later. When it is neutrally buoyant, dry off the ROV and glue all the pipes together.
The finished ROV should look like this: