AMI system FAQ

The Automated Monitoring of Insects system (AMI system) is a solar-powered system for monitoring nocturnal insects. AMI systems are used by researchers around the world and on this page we aim to capture the frequently asked questions around using and troubleshooting the AMI system. For any questions that are not answered here please contact the AMI support team on ami-trap@ceh.ac.uk

Software troubleshooting

Can you tell me step by step how I can change both Rock Pi and Raspberry Pi to turn off the motion trigger?

For Raspberry Pi based systems, the motion software is invoked / started upon boot in the file /etc/rc.local , you will need to modify the line inside this file to update the line which says only "motion" to "motion -m". That is you are adding "-m" after a space to the existing line

For Rock board based systems you will need to do the above in this file : /root/start_motion.sh (instead of rc.local in Raspi)

Can you tell me step by step how I can change both Rock Pi and Raspberry Pi to turn on the motion trigger?

For Rock board based systems you will need to do the above in this file : /root/start_motion.sh (instead of rc.local in Raspi)

How do I configure the snapshot interval for taking pictures to just 10 second snapshots and not automatic camera movement detection?

After the above steps to disable motion activation.

Modify motion.conf file to take snapshots every 10 seconds, this file is located at: /etc/motion/motion.conf

Navigate to the section snapshot_interval and edit the numbers after the space to reflect the seconds for the interval at which images is to be captured, shown here for 10 seconds: snapshot_interval 10

How do we set the clock on the AMI?

Why are my Clock settings incorrect / outdated?

Clock can only be set using the command terminal on the AMIs delivered prior to 2025, steps below with commands:

Check the Current Time Zone: timedatectl
If necessary, update the Time Zone: sudo timedatectl set-timezone Europe/London
Note: You can review available time zones using: timedatectl list-timezones | grep Europe
If you updated the time zone, verify it has been updated correctly: timedatectl
Update the system's date and time: sudo date-s "2024-05-20 11:34"
Verify the date and time: date
Then you need to write the time into the RTC battery with the following command: sudo hwclock w
Confirm the RTC battery time is correct: sudo hwclock - r

The battery supporting the real-time clocks has gone flat. How can I replace this battery?

I have a question about the setting of the real time clock via the Rock Pi computer. We did that, but after we turned off the system, the next day the time was the time that we set the previous day. So it wasn't updated when the system was off. Do you think that this is due to wearing out of RTC batteries?

Real Time Clock (RTC) battery. As shown in the electronics box. Battery type CR1220. Expected life cycle: 5 years. Suggested to change every 1 year as it s not worth the risk of it failing. Once this is replaced, please follow the steps for checking and setting the RTC to the current time for the area of deployment. https://www.batterystation.co.uk/battery-types/button-cells-coin-cells/cr1220-coin-cells.html

AMI traps with a Raspberry Pi should use this battery: https://www.batterystation.co.uk/battery-types/button-cells-coin-cells/cr1220-coin-cells.html

AMI traps with a Rock 4 SE Pi should use this battery: Rockpi4/hardware/rtc - Radxa Wiki

Why is my AMI system not generating any images?

The motion detection system may have stopped turning on automatically

Try to restart the system.

The SSD may not be mounted or detected.

In the scenario where the AMI-trap is turned on and the SSD drive is not connected, or the PI, for some reason, does not detect the drive, the system will save images to the SD card rather than the SSD drive. To fix this we need to check if images have been saved to the SD card and remove them, and then check that we can get the SSD drive connected properly. These instructions will take you through these steps for the Raspberry Pi setup and the Rock Pi setup.

The camera is disconnected or not detected

Check section in manual about camera configuration and ensure wiring is correct

Why is my AMI (Raspberry Pi) not booting and blank screen when connected to a monitor?

Make sure a micro-SD card with the correct image is present on the Raspberry Pi
The HDMI cable may not be plugged in correctly or there is a non-HDMI interface being added (converter to VGA for example)
The SSD was disconnected and due to this all images were stored to the micro-SD card causing the boot drive to be full
If booting is not possible even after multiple attempts, try to create a new micro-SD card image

Why is my AMI generating images that are grey?

This indicates that the camera has not been detected, ensure camera cable is plugged into the Raspberry Pi and the other end is not unplugged inside the camera + LED housing.

Ensure that the camera ID is configured correctly in the appropriate files [camera1.conf, motion.conf and setCamera.sh files as mentioned in the user manual section: Motion and camera configuration files]

Troubleshooting electronics

Why are the Camera Flash LED and LepiLED Lights not turning ON, but Raspberry Pi is turning ON?

Check voltages using a multi-meter to make sure there is enough battery charge and is well above 12V [check section Connecting to Power in the user manual]

Ensure wiring of the lights is as shown in the user manual [Connecting Camera and Light Ring]

Why is my AMI Raspberry Pi not turning ON?

Check to ensure the system can turn ON using the timer switch (using the MAN button on the timer switch)

Check wiring of the Raspberry Pi, and that it matches the plans in the user manual (REF to the FIGURE 1: BLOCK DIAGRAM OF AMI-TRAP COMPONENTS in the user manual)

Power components, electricals and other related accessories

Is it normal to purchase the battery supply box from UKCEH?

Yes, the version with the battery supply box is standard, and is what is recommended by UKCEH. Without the battery supply box, it would be much more complex to power the system and protect the battery + solar charging electronic components.

What kind of battery can be used to power the AMI?

What is the standard battery setup used by UKCEH?

UKCEH recommend using 2 12V lead acid deep cycle batteries (sometimes called marine batteries ) in parallel. The battery supply box has space to connect two batteries, and UKCEH recommend multiple batteries so that it takes longer for them to go dead (going dead reduces the useful lifetime of a lead acid battery).
However, a single battery with a higher capacity (as measured in AH or ampere-hours) can also do the job; a 100Ah battery is recommended.
Lead acid batteries come in different types, for example flooded lead-acid batteries, gel batteries, and AGM (Absorbent Glass Mat) batteries. Above all it is recommended that the batteries are sealed (typical of AGM and gel batteries). While gel batteries are not recommended by UKCEH, some of our partners have used these types of battery with AMI systems with no issues.
We recommend using AGM deep cycle / marine batteries for durability and maintenance reasons. Gel batteries do not last as long as the AGM ones (Try not to use non flooded batteries as a minimum requirement)

Can the AMI trap be run from a mains electrical supply?

The AMI trap has been designed to receive power from a solar panel attached to a battery and to run on 12 v DC power supply. The AMI traps have been tested and certified with this power source and configuration.

While it should be a relatively simple task for the system to be altered by a qualified electrical engineer post manufacture to accept mains power with the use of a suitable 12v power converter and adaptor we cannot adapt the system ourselves for customers, or advise them on how to do this, as this would require a re-certification.

Solar panel(s) and charging

What are the other important parameters to keep in mind for solar panels and charging the AMI batteries?

The crucial thing is that the solar panel is capable of charging a 12v battery, and is compatible with the Sunsaver 20l charge controller that the UKCEH battery supply box comes with. This means that the max output voltage of the panel must be below the max input voltage of the Sunsaver 20l (30v). Good options exist for panels with output voltage of ~20v.

It is also important that the solar panel generates sufficient power. UKCEH recommend running two 100w solar panels in parallel, both attached to the Sunsaver20l. Of course, this can also be provided by a single 200w panel. Some of our partners have had reasonable success with a single 175w panel. Power is likely to be a limiting factor in woodland environments and we do not recommend deployments under closed canopy.

It will be important not to have the AMI running too late in the season when there is little sun. In periods of limited sunlight, you can adjust the sampling period to prevent draining the batteries repeatedly.

What are the general considerations for solar panel hookup?

You will need to check which cables your solar panels come with, if any. You may need to purchase them separately. We recommend 6mm² cables of a minimum 5m, and longer may be needed in some environments (don t go too long, or you risk losing power). The common connector for solar panels is called MC4, and the side that connects to the Sunsaver 20l may be cut and stripped if needed.

How is the mounting of solar panels taken care of?

Please make sure when purchasing your panels that the panels are compatible with charge controller, by checking the panel specs against the Sunsaver charge controller specs.

You will need a way to mount the solar panel. Some solutions are available from the solar panel providers, but these may be expensive. Affordable options are available from Amazon and elsewhere, and they can be used to mount the panel on the ground or onto a pole or tree. The mount should be used to ensure the panel is oriented towards the sun at midday (south for deployments in the northern hemisphere, and north for deployments in the southern hemisphere) and tilted at an angle roughly equal to the latitude of the sample site.

What is the standard UKCEH solar panel setup?

2 x 100-watt solar panels in parallel (12V panels)
Because we use the Sunsaver-20L charge controller (12V), Max open circuit voltage (Voc): 25 V and Max short circuit current (Isc): 25 A

Learning how to use the device

How hard is it to learn how to use the device?

It s an autonomous system, with the given user manual it should be straightforward to use and configure for operation times.
Having knowledge of linux based systems helps in configuring systems to your requirements as needed, but not necessary for using the system itself.
AMI is designed to be used by anyone who can read documentation in English with ease, without any formal background in computer science or engineering. (We do have some material in Spanish prepared for some field partners overseas, please contact us if you think this would be useful to you)

What are the most important considerations for us to be sure we re using/positioning the device effectively for monitoring?

When positioning the AMI system you should keep in mind visibility, to enable maximum dispersion of the light, this may be purely determined by the target species or landscape being studied.
System should be placed away from other light sources to have the highest possible attraction for moths from the lights provided.
Solar panels should be placed at specific angles and directions based on the latitudes the system is being deployed at using online tools

Lights

Which type of LepiLED is used (Standard, Mini, Maxi, Maxi Switch, Mini Switch)?

We have found the Standard model to be most effective and compatible with our systems

What LED lights are used/what is their strength?

This link has the specs directly from the manufacturer

How far away can the lights be seen by a person if the device is deployed in a forest?

This depends on the tree density of the forest. We have not explicitly tested the visibility of LepiLED in different scenarios. However, the LED light is bright, and with clear line of sight would be visible over hundreds of meters.

Have you tested the distance from which moths are attracted to the device? (Obviously this will vary by the species, sex, etc.)

We have not tested this explicitly, but estimate the attraction range to be tens of meters

Capturing images

Can the device be programmed to automatically turn on and off at particular times? If so, can you program different times for different dates (e.g. loading in a sunset/sunrise schedule that varies throughout the course of the season)?

The timer relay switch takes the ON and OFF times through an easy-to-use programming interface, it is programmable based on the days of the week rather than the dates of the month.
As of now, the system is unable to work off the sunrise and sunset time variations automatically and this will need to be manually programmed by the user.
Future versions may incorporate this feature and this section will be updated as and when that happens.

If we set up the camera settings at home/in a backyard, will they work equally well for other locations? For example, will we have to adjust the tilt and focus of the camera each time we move it, or will the angle/distance of the camera compared to the white sheet stay the same?

Camera settings are tested and set to work for post-dusk operations when the ambient light is the lowest, this should work well as long as the settings for ON/OFF times are considered according to the atmospheric light conditions (i.e. the system should not be set to come on when it is still light outside).
All camera and light settings are fixed in the AMI system and will not need variation / readjustments by the user. Specific camera parameters can be adjusted to one's suitability based on need and preference to their analysis methods.

Could you recommend an image resolution that people tend to use for enough detail for automated detection and classification?

The image resolution configured by default on the systems is 4906 x 2160
This is the same image resolution being used by all our partners and the algorithms being developed by MILA and Turing

About how many images of each resolution does the 500GB SSD store?

Each image after compression is about 1-2 MB and this is dependent on various factors, a 500GB SSD can allow for up to 500,000 images
The file size is variable based on the settings configured for the camera and image resolution, along with the camera unit compressing the images

Moving the device

If you must move the device often based on deployment strategies, some of the below points will be good to consider

What parts of the device are fragile?

LepiLED
RTC
Camera housing
Contents of the electronics enclosure

Would you recommend taking the device fully apart before moving it, then putting it back together? How long does it take to take the device apart and put it back together?

Not necessary to disassemble for moving in supervised conditions, unless it is being boxed and shipped
The time taken to take device apart and assembled back is based on abilities and familiarity along with tools available, roughly 45 mins to an hour.

Do we need to seal off the gap between the battery box and the base plate under the camera?

This procedure is shown in this video, but we do not have evidence to suggest that this is needed.

What tools or supplies should we purchase to put together/take down the device?

Allen keys
Flat head screwdriver

Setup

After we set up the Raspberry Pi once in the lab with an internet connection and monitor, will we need to do any additional setup in the field?

SSH connection is possible in field using the LAN cable, but no additional set up is required. It can be useful however to ensure the system is functioning as expected, i.e. by checking to see that images are being taken once it is turned on.

Would it help us to have a mini-Raspberry Pi screen out in the field to troubleshoot?

Helpful if you are comfortable using it, we have not tested this but rely on SSH

Should we manually shut down and restart the Raspberry Pi whenever we move the device? Will we have to manually re-apply any settings if we turn the Raspberry Pi off?

Turning the system OFF using the Timer relay switch manually (if not already OFF due to programmed setting) would be a good idea before moving. Settings will be retained.

Would you recommend testing the device (e.g. turning on device, triggering motion manually) each time we move the device?

Not necessary but if the moving involved shaking / strong vibrations then the connections might have gotten loose, in which case it may be wise to test the system, to be on the safe side

Any other recommendations or considerations to keep in mind for moving the device?

Minimize vibrations once assembled and tested.
Protect the RTC and LepiLED glass

Miscellaneous

What can I do to help prevent water getting into the system

Before deployment, make sure all cable glands are hand tight to maintain the water ingress protection and prevent rain getting into the systems.
UKCEH strongly suggests the use of desiccant packs to keep the atmospheres dry inside the electronics enclosure.

Would it be possible for us to use a lightweight lithium ion 12V battery? What specs should we consider when selecting a battery (e.g. mAh, shape of/distance between connector terminals)

As long as you can supply 12V to the unit using those batteries with 100AH capacity for every 3 nights
We have not tested these for lithium batteries and would not be able to comment

Any recommendations for safely using the lithium battery?

We cannot comment on this since we have not tested the Lithium power options.

Does the device sense ambient environmental light? Do you have any experience with automated ambient light sensing to control for the impact of ambient light on the likelihood of attracting moths?

We do not have ambient environmental light sensing at this point
Device is mainly operated after sunset and before sunrise hence we do not see the need at this time

If anything on the device breaks, what would be likely to break? Would it be easy for us to find spare parts at a general hardware store and/or repair the device ourselves?

LepiLED
Most other components are available from manufacturers
It may be possible for UKCEH enterprise also to support, as needed

What exactly does the Watchdog do?

Enables the safe shutdown of the Raspberry Pi preventing corruption of images and file system, along with keeping the clock using the Real-time clock when power is cut.

Have you compared the performance of the AMI-trap against that of a more traditional lethal light trapping technique?

We have done such a study in 2023 and are currently evaluating the data

Getting an error when writing the time to the RTC battery.

Follow the instructions in this document