Marty V2 comes with one sensor attached to each foot, but each foot can hold a sensor at both the front and the rear. To connect two sensors on one foot, use a **sensor bridging cable** to join them in a daisy chain.

===== Set Up =====

Marty foot sensors can be fitted to the front or back of either foot. Before fitting them, consider:

  * **Sensing direction:** IR and colour sensors detect the environment in front of and below them. Point each sensor in the direction you want Marty to sense.
  * **Cable routing:** Marty's leg movements can catch or tangle extra wiring. Use the sensor bridging cables supplied with Marty and route them as shown below so they do not restrict movement.

Turn Marty off before changing sensor wiring.

The video demonstrates how to connect two sensors to one foot:

{{ youtube>mr0PqGRA24g?medium }}

{{ :martyv2:userguides:sensorsandaddons:bridgingcable1.jpeg?nolink&392 |Sensor bridging cable for connecting two foot sensors}}

<html><span id="step_1_decide_where_to_mount_your_sensors"></span></html>

==== Decide where to mount your sensors ====

In this example, the **IR sensor is at the front** of the foot and the **colour sensor is at the back**.

<html><span id="step_2_connect_the_sensors_together"></span></html>

==== Connect the sensors together ====

Connect a sensor bridging cable to the **top-mounted connector port on each sensor**. Bridging cables are supplied with each add-on or in your Marty box.

**Pass the cable through the middle of Marty's leg.** You may need to unscrew the sensors from the foot to make enough room to plug in the cable.

{{ :martyv2:userguides:sensorsandaddons:twosensorsconnected1.jpeg?nolink&400 |Two foot sensors joined by a bridging cable}}

{{ :martyv2:userguides:sensorsandaddons:twosesnorsconnected2.jpeg?nolink&400 |Bridging cable routed through the middle of Marty's leg}}

<html><span id="step_3_make_sure_both_sensors_are_fixed_to_the_foot"></span></html>

==== Fix both sensors to the foot ====

Use **two M3 nuts and bolts** to secure the sensors to the foot.

{{ :martyv2:userguides:sensorsandaddons:screwedin1.jpeg?nolink&400 |Both sensors secured to Marty's foot}}

===== Checking and Configuring the Sensors =====

  - Open the [[:martyv2:userguides:app|Robotical app]] and connect to Marty.
  - Open **Robot settings → Add-ons** to reach **Manage Add-ons**.
  - Check that both connected sensors appear in the list.
  - Select a sensor's row or gear icon to expand its details, then follow the relevant sensor guide to finish setup.

The current Manage Add-ons screen shows the connected sensors and their names. The grey **Not Connected** entry is a saved configuration, rather than a currently detected sensor.

{{ :martyv2:userguides:sensorsandaddons:ir-addons-settings-2026-10.png?nolink&780 |Current Manage Add-ons screen showing connected IR and colour sensors}}

For the sensors used in this example, follow the [[:martyv2:userguides:sensorsandaddons:groundcontact|IR sensor guide]] and the [[:martyv2:userguides:sensorsandaddons:colorsensor|colour sensor guide]] to complete configuration.