Agricultural Drone Sensor

Services:  CNC milling, sandblasting, anodizing, laser marking

Material:  Aluminum 6061-T6

Qty:  200 sets

The Product Developers

MicaSense is a team of engineers, remote sensing scientists, GIS specialists, and friendly people passionate about agriculture. They provide a variety of hardware solutions to help agriculture professionals and companies make the right decisions about their fields.

“In addition to the technical services Star lends, the presence of regional sales engineers also greatly improves the experience by enabling face-to-face discussions, promoting quality standards and general vendor-client relationship building. “
Steven Larsen
Lead Mechanical Engineer and Production Manager, MicaSense

The Project

Our team at Star Rapid was approached by MicaSense to help them build an enclosure for their agricultural drone sensor that could resist the toughest outdoor environments. The enclosure is made of three parts, milled from aluminum 6061 with a T6 temper. Some of the parts were color anodized, while others were given a clear alodine coating.

Drone-mounted Altum by MicaSense
Altum can be mounted on and controlled by many commercial UAVs. Image courtesy of MicaSense

Design For Manufacturing Review

To get the project started, once we receive the full product design files from our customers we carefully review the engineering files, identify discrepancies if there are any, or point out areas that may need to be modified to improve manufacturability.

When working with MicaSense the following areas were discussed:

#1 Design For Manufacturing Recommendation

The areas marked in green needed to be post-machined to achieve the required flatness and tolerance after anodizing. We shared our concern with the client, that machining right up to the wall of the part would damage the adjacent coated surface.

The client preferred to leave this area unaffected, so instead we modified our cutting program to move away from the wall by .5mm, which would retain the anodized surface yet achieve the necessary flatness on most of the face.

Star Rapid CAD file detail for MicaSense
It’s possible that the anodizing could be damaged in the area marked in red.

#2 Design For Manufacturing Recommendation

The area indicated shows the transition where two planes meet at right angles. The CAD file shows the transition at this area to be a sharp 90°, but in reality we needed to machine it with a radius of R2, or 2mm.  A slight radius is always unavoidable when working with rotating cutting tools. This was acceptable to the customer.

CAD image detail, Star Rapid, Micasense case study
A small radius here is unavoidable but does not affect the functionality of the part.

#3 Design For Manufacturing Recommendation

Most of the corner fins show a smooth, convex transition from the rounded corner to the flat face. However, the top one, marked in red, appeared to differ in geometry with an inverse radius.

We were concerned that this might have been a design error. After consulting with the customer, they confirmed that this was a deliberate design and therefore the CAD drawing was left unmodified. This represents just part of the process we go through to ensure every detail is correct before we begin cutting any metal.

Star Rapid CAD image detail for MicaSense case study
We needed to confirm if the above indicated area was intentional or not.

Material Inspection

As we do with all of our projects, we double-checked that the incoming raw material marked as “AL 6061-T6” was exactly that.

Oxford Instruments XRF being used at Star Rapid
We used our Oxford Instruments XRF gun to identify the chemical composition of the metal and confirm that it was 6061.
Hardness testing of AL-6061 at Star Rapid
Then the hardness of the metal was checked to confirm a T6 temper.

CNC Milling

Once the raw material was prepared, we built separate holding fixtures for each of the three components.

Milling MicaSense cover plates
Milling two parts at one time
MicaSense enclosure cover detail
Detail of enclosure cover, exterior surface.

The cover for the enclosure needed to be milled on both sides. The most efficient way to do this was by putting two fixtures into one machine. After completing one side the part was removed, flipped over, placed on the adjacent fixture and completed.

MicaSense enclosure cover, interior detail
Detail of enclosure, interior surface.
Middle section, MicaSense Altum, anodized, at Star Rapid
Here is the middle section of the enclosure, after milling and anodizing.
Spraying air on MicaSense milled part at Star Rapid
Detail of enclosure, interior surface.
MicaSense anodized parts for comparison, Star Rapid
The post-machined areas, shown as raw metal on the left, needed to be flattened precisely to form mating surfaces for other components to be added later.


Freshly milled aluminum has a polished look that is almost as shiny as chrome. Unless treated, this surface will quickly oxidize when exposed to the atmosphere.

Sandblasting at Star Rapid for MicaSense
Freshly milled parts being loaded into the blasting cabinet
After sandblasting, MicaSense at Star Rapid
Sandblasting, before and after

After sandblasting, the parts achieve a uniform matte finish. The middle section and the enclosure cover were then given a clear alodine coating. An alodine finish is a chemical treatment used on aluminum, magnesium and other metals to provide corrosion protection and to act as a base for other surface treatments like painting or powder coating. Alodine finishes are usually transparent.


Laser Marking

After sandblasting, both the top and bottom sections were laser marked.

Laser etched Altum part by Star Rapid
The laser is able to etch away a very fine layer of material right at the surface.
Barcode detail for MicaSense case study at Star Rapid
Barcodes were laser marked to assist in product tracking
Parts are soaked for about one hour
"One of the greatest benefits for small to midsize businesses is Star’s ability to deliver product in an end-to-end solution, meaning they complete the machining processes, anodization process, and laser etching"
Steven Larsen
Lead Mechanical Engineer and Production Manager, MicaSense