sciBot EMG Sensor

The sciBot project uses RCA plugs and jacks as the standard connector for sensors, actuators, and accessories. Since we want to connect an EMG sensor to our sciBot, we must attach it to a set of RCA plugs.

We want one end of our potentiometer hooked up to +5V (the centre pin of the red RCA plug), the other end hooked up to ground (the shield on both RCA plugs), and the wiper is attached to an input on the Arduino (the centre pin of the white RCA plug).

 

 

Materials

Image Quantity Description Manufacturer Vendor
½ RCA extension cable Chateau 706-72 Dollar Tree
1 MyoWare Muscle Sensor SparkFun SEN-13723 DigiKey 1568-1514-ND
1 3/8″ (9.5 mm) 3:1 adhesive heat shrink, cut to 10 mm Qualtek Q5-3X-3/8-01-QB48IN-25 DigiKey Q53X038B-ND
1 3/8″ (9.5 mm) 3:1 adhesive heat shrink, cut to 30 mm Qualtek Q5-3X-3/8-01-QB48IN-25 DigiKey Q53X038B-ND

 

 

Instructions

Step 1

Cut the RCA extension cable about 20 cm from the jack end. Save the jacks for making an RCA Jack to RJ25 Adaptor.

Cut the cable to whatever length you want. In the following pictures, it has been left about 70 cm long, as that was the desired size for this EMG sensor.

 

Step 2

Put the small piece of adhesive heat shrink over the cable, and slide down to where the red and white cables split. Heat the heat shrink so that it prevents the cable from being pulled apart at the plugs.

Step 3

Pull apart about 4 cm of the cut RCA cable. Strip about 1 cm of the outer insulation from each wire, and strip about 3 mm of the inner insulation.

Step 4

Tin the exposed wires.

Step 5

Put the heat shrink over the cable, out of the way.

Step 6

2 of the wires should be the same colour – these are the ground wires, connected to the outside of the RCA plug. Use a continuity tester to ensure that this is true.

Put these two wires through the hole labelled “-” at one end of the MyoWare board, and solder them into place.

With a continuity tester, determine which of the remaining 2 wires is connected to the middle of the red RCA plug. Solder this wire to the hole labelled “+”.

Solder the remaining wire to the hole labelled “Sig”.

Step 7

Slide the heat shrink up over the wires, and use a hot air gun to shrink it into place.

Step 8

Put a bit of hot melt glue around the wires where they connect to the MyoWare board. Make sure to put the glue on both sides, and cover both the cable and the board.

Step 9

Congratulations! You have completed making the sciBot EMG Sensor.